Imported Upstream version 1.9.1

author: bertagaz <bertagaz@ptitcanardnoir.org> 2012-06-12 00:37:08 +0200
committer: bertagaz <bertagaz@ptitcanardnoir.org> 2012-06-12 00:37:08 +0200
commit: 70b0e555ef5f880c08f09331946c83744ca310a5 (patch)
tree: e673bf4dae733ca8f2faa5a030e22f9015070dce /NEWS.rst
parent: e28117a205c07306a8ba8f502441a7b304669c41 (diff)
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+
+==================================
+User-Visible Changes in Tahoe-LAFS
+==================================
+
+Release 1.9.1 (2012-01-12)
+--------------------------
+
+Security-related Bugfix
+'''''''''''''''''''''''
+
+- Fix flaw that would allow servers to cause undetected corruption when
+  retrieving the contents of mutable files (both SDMF and MDMF). (`#1654`_)
+
+.. _`#1654`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1654
+
+
+Release 1.9.0 (2011-10-30)
+--------------------------
+
+New Features
+''''''''''''
+
+- The most significant new feature in this release is MDMF: "Medium-size
+  Distributed Mutable Files". Unlike standard SDMF files, these provide
+  efficient partial-access (reading and modifying small portions of the file
+  instead of the whole thing). MDMF is opt-in (it is not yet the default
+  format for mutable files), both to ensure compatibility with previous
+  versions, and because the algorithm does not yet meet memory-usage goals.
+  Enable it with ``--format=MDMF`` in the CLI (``tahoe put`` and ``tahoe
+  mkdir``), or the "format" radioboxes in the web interface. See
+  `<docs/specifications/mutable.rst>`_ for more details (`#393`_, `#1507`_)
+- A "blacklist" feature allows blocking access to specific files through
+  a particular gateway. See the "Access Blacklist" section of
+  `<docs/configuration.rst>`_ for more details. (`#1425`_)
+- A "drop-upload" feature has been added, which allows you to upload
+  files to a Tahoe-LAFS directory just by writing them to a local
+  directory. This feature is experimental and should not be relied on
+  to store the only copy of valuable data. It is currently available
+  only on Linux. See `<docs/frontends/drop-upload.rst>`_ for documentation.
+  (`#1429`_)
+- The timeline of immutable downloads can be viewed using a zoomable and
+  pannable JavaScript-based visualization. This is accessed using the
+  'timeline' link on the File Download Status page for the download, which
+  can be reached from the Recent Uploads and Downloads page.
+
+Configuration/Behavior Changes
+''''''''''''''''''''''''''''''
+
+- Prior to Tahoe-LAFS v1.3, the configuration of some node options could
+  be specified using individual config files rather than via ``tahoe.cfg``.
+  These files now cause an error if present. (`#1385`_)
+- Storage servers now calculate their remaining space based on the filesystem
+  containing the ``storage/shares/`` directory. Previously they looked at the
+  filesystem containing the ``storage/`` directory. This allows
+  ``storage/shares/``, rather than ``storage/``, to be a mount point or a
+  symlink pointing to another filesystem. (`#1384`_)
+- ``tahoe cp xyz MUTABLE`` will modify the existing mutable file instead of
+  creating a new one. (`#1304`_)
+- The button for unlinking a file from its directory on a WUI directory
+  listing is now labelled "unlink" rather than "del". (`#1104`_)
+
+Notable Bugfixes
+''''''''''''''''
+
+- The security bugfix for the vulnerability allowing deletion of shares,
+  detailed in the news for v1.8.3 below, is also included in this
+  release. (`#1528`_)
+- Some cases of immutable upload, for example using the ``tahoe put`` and
+  ``tahoe cp`` commands or SFTP, did not appear in the history of Recent
+  Uploads and Downloads. (`#1079`_)
+- The memory footprint of the verifier has been reduced by serializing
+  block fetches. (`#1395`_)
+- Large immutable downloads are now a little faster than in v1.8.3 (about
+  5% on a fast network). (`#1268`_)
+
+Packaging Changes
+'''''''''''''''''
+
+- The files related to Debian packaging have been removed from the Tahoe
+  source tree, since they are now maintained as part of the official
+  Debian packages. (`#1454`_)
+- The unmaintained FUSE plugins were removed from the source tree. See
+  ``docs/frontends/FTP-and-SFTP.rst`` for how to mount a Tahoe filesystem on
+  Unix via sshfs. (`#1409`_)
+- The Tahoe licenses now give explicit permission to combine Tahoe-LAFS
+  with code distributed under the following additional open-source licenses
+  (any version of each):
+
+  * Academic Free License
+  * Apple Public Source License
+  * BitTorrent Open Source License
+  * Lucent Public License
+  * Jabber Open Source License
+  * Common Development and Distribution License
+  * Microsoft Public License
+  * Microsoft Reciprocal License
+  * Sun Industry Standards Source License
+  * Open Software License
+
+Compatibility and Dependencies
+''''''''''''''''''''''''''''''
+
+- To resolve an incompatibility between Nevow and zope.interface (versions
+  3.6.3 and 3.6.4), Tahoe-LAFS now requires an earlier or later
+  version of zope.interface. (`#1435`_)
+- The Twisted dependency has been raised to version 10.1 to ensure we no
+  longer require pywin32 on Windows, the new drop-upload feature has the
+  required support from Twisted on Linux, and that it is never necessary to
+  patch Twisted in order to use the FTP frontend. (`#1274`_, `#1429`_,
+  `#1438`_)
+- An explicit dependency on pyOpenSSL has been added, replacing the indirect
+  dependency via the "secure_connections" option of foolscap. (`#1383`_)
+
+Minor Changes
+'''''''''''''
+
+- A ``man`` page has been added (`#1420`_). All other docs are in ReST
+  format.
+- The ``tahoe_files`` munin plugin reported an incorrect count of the number
+  of share files. (`#1391`_)
+- Minor documentation updates: #627, #1104, #1225, #1297, #1342, #1404
+- Other minor changes: #636, #1355, #1363, #1366, #1388, #1392, #1412, #1344,
+  #1347, #1359, #1389, #1441, #1442, #1446, #1474, #1503
+
+.. _`#393`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/393
+.. _`#1079`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1079
+.. _`#1104`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1104
+.. _`#1268`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1268
+.. _`#1274`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1274
+.. _`#1304`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1304
+.. _`#1355`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1355
+.. _`#1383`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1383
+.. _`#1384`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1384
+.. _`#1385`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1385
+.. _`#1388`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1388
+.. _`#1391`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1391
+.. _`#1392`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1392
+.. _`#1395`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1395
+.. _`#1409`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1409
+.. _`#1420`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1420
+.. _`#1425`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1425
+.. _`#1429`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1429
+.. _`#1435`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1435
+.. _`#1438`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1438
+.. _`#1454`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1454
+.. _`#1507`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1507
+
+
+Release 1.8.3 (2011-09-13)
+--------------------------
+
+Security-related Bugfix
+'''''''''''''''''''''''
+
+- Fix flaw that would allow a person who knows a storage index of a file to
+  delete shares of that file. (`#1528`_)
+- Remove corner cases in mutable file bounds management which could expose
+  extra lease info or old share data (from prior versions of the mutable
+  file) if someone with write authority to that mutable file exercised these
+  corner cases in a way that no actual Tahoe-LAFS client does. (Probably not
+  exploitable.) (`#1528`_)
+
+.. _`#1528`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1528
+
+
+Release 1.8.2 (2011-01-30)
+--------------------------
+
+Compatibility and Dependencies
+''''''''''''''''''''''''''''''
+
+- Tahoe is now compatible with Twisted-10.2 (released last month), as
+  well as with earlier versions. The previous Tahoe-1.8.1 release
+  failed to run against Twisted-10.2, raising an AttributeError on
+  StreamServerEndpointService (`#1286`_)
+- Tahoe now depends upon the "mock" testing library, and the foolscap
+  dependency was raised to 0.6.1 . It no longer requires pywin32
+  (which was used only on windows). Future developers should note that
+  reactor.spawnProcess and derivatives may no longer be used inside
+  Tahoe code.
+
+Other Changes
+'''''''''''''
+
+- the default reserved_space value for new storage nodes is 1 GB
+  (`#1208`_)
+- documentation is now in reStructuredText (.rst) format
+- "tahoe cp" should now handle non-ASCII filenames
+- the unmaintained Mac/Windows GUI applications have been removed
+  (`#1282`_)
+- tahoe processes should appear in top and ps as "tahoe", not
+  "python", on some unix platforms. (`#174`_)
+- "tahoe debug trial" can be used to run the test suite (`#1296`_)
+- the SFTP frontend now reports unknown sizes as "0" instead of "?",
+  to improve compatibility with clients like FileZilla (`#1337`_)
+- "tahoe --version" should now report correct values in situations
+  where 1.8.1 might have been wrong (`#1287`_)
+
+.. _`#174`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/174
+.. _`#1208`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1208
+.. _`#1282`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1282
+.. _`#1286`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1286
+.. _`#1287`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1287
+.. _`#1296`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1296
+.. _`#1337`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1337
+
+
+Release 1.8.1 (2010-10-28)
+--------------------------
+
+Bugfixes and Improvements
+'''''''''''''''''''''''''
+
+- Allow the repairer to improve the health of a file by uploading some
+  shares, even if it cannot achieve the configured happiness
+  threshold. This fixes a regression introduced between v1.7.1 and
+  v1.8.0. (`#1212`_)
+- Fix a memory leak in the ResponseCache which is used during mutable
+  file/directory operations. (`#1045`_)
+- Fix a regression and add a performance improvement in the
+  downloader.  This issue caused repair to fail in some special
+  cases. (`#1223`_)
+- Fix a bug that caused 'tahoe cp' to fail for a grid-to-grid copy
+  involving a non-ASCII filename. (`#1224`_)
+- Fix a rarely-encountered bug involving printing large strings to the
+  console on Windows. (`#1232`_)
+- Perform ~ expansion in the --exclude-from filename argument to
+  'tahoe backup'. (`#1241`_)
+- The CLI's 'tahoe mv' and 'tahoe ln' commands previously would try to
+  use an HTTP proxy if the HTTP_PROXY environment variable was set.
+  These now always connect directly to the WAPI, thus avoiding giving
+  caps to the HTTP proxy (and also avoiding failures in the case that
+  the proxy is failing or requires authentication). (`#1253`_)
+- The CLI now correctly reports failure in the case that 'tahoe mv'
+  fails to unlink the file from its old location. (`#1255`_)
+- 'tahoe start' now gives a more positive indication that the node has
+  started. (`#71`_)
+- The arguments seen by 'ps' or other tools for node processes are now
+  more useful (in particular, they include the path of the 'tahoe'
+  script, rather than an obscure tool named 'twistd'). (`#174`_)
+
+Removed Features
+''''''''''''''''
+
+- The tahoe start/stop/restart and node creation commands no longer
+  accept the -m or --multiple option, for consistency between
+  platforms.  (`#1262`_)
+
+Packaging
+'''''''''
+
+- We now host binary packages so that users on certain operating
+  systems can install without having a compiler.
+  <https://tahoe-lafs.org/source/tahoe-lafs/deps/tahoe-lafs-dep-eggs/README.html>
+- Use a newer version of a dependency if needed, even if an older
+  version is installed. This would previously cause a VersionConflict
+  error. (`#1190`_)
+- Use a precompiled binary of a dependency if one with a sufficiently
+  high version number is available, instead of attempting to compile
+  the dependency from source, even if the source version has a higher
+  version number. (`#1233`_)
+
+Documentation
+'''''''''''''
+
+- All current documentation in .txt format has been converted to .rst
+  format. (`#1225`_)
+- Added docs/backdoors.rst declaring that we won't add backdoors to
+  Tahoe-LAFS, or add anything to facilitate government access to data.
+  (`#1216`_)
+
+.. _`#71`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/71
+.. _`#174`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/174
+.. _`#1212`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1212
+.. _`#1045`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1045
+.. _`#1190`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1190
+.. _`#1216`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1216
+.. _`#1223`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1223
+.. _`#1224`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1224
+.. _`#1225`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1225
+.. _`#1232`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1232
+.. _`#1233`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1233
+.. _`#1241`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1241
+.. _`#1253`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1253
+.. _`#1255`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1255
+.. _`#1262`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1262
+
+
+Release 1.8.0 (2010-09-23)
+--------------------------
+
+New Features
+''''''''''''
+
+- A completely new downloader which improves performance and
+  robustness of immutable-file downloads. It uses the fastest K
+  servers to download the data in K-way parallel. It automatically
+  fails over to alternate servers if servers fail in mid-download. It
+  allows seeking to arbitrary locations in the file (the previous
+  downloader which would only read the entire file sequentially from
+  beginning to end). It minimizes unnecessary round trips and
+  unnecessary bytes transferred to improve performance. It sends
+  requests to fewer servers to reduce the load on servers (the
+  previous one would send a small request to every server for every
+  download) (`#287`_, `#288`_, `#448`_, `#798`_, `#800`_, `#990`_,
+  `#1170`_, `#1191`_)
+- Non-ASCII command-line arguments and non-ASCII outputs now work on
+  Windows. In addition, the command-line tool now works on 64-bit
+  Windows. (`#1074`_)
+
+Bugfixes and Improvements
+'''''''''''''''''''''''''
+
+- Document and clean up the command-line options for specifying the
+  node's base directory. (`#188`_, `#706`_, `#715`_, `#772`_,
+  `#1108`_)
+- The default node directory for Windows is ".tahoe" in the user's
+  home directory, the same as on other platforms. (`#890`_)
+- Fix a case in which full cap URIs could be logged. (`#685`_,
+  `#1155`_)
+- Fix bug in WUI in Python 2.5 when the system clock is set back to
+  1969. Now you can use Tahoe-LAFS with Python 2.5 and set your system
+  clock to 1969 and still use the WUI. (`#1055`_)
+- Many improvements in code organization, tests, logging,
+  documentation, and packaging. (`#983`_, `#1074`_, `#1108`_,
+  `#1127`_, `#1129`_, `#1131`_, `#1166`_, `#1175`_)
+
+Dependency Updates
+''''''''''''''''''
+
+- on x86 and x86-64 platforms, pycryptopp >= 0.5.20
+- pycrypto 2.2 is excluded due to a bug
+
+.. _`#188`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/188
+.. _`#287`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/287
+.. _`#288`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/288
+.. _`#448`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/448
+.. _`#685`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/685
+.. _`#706`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/706
+.. _`#715`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/715
+.. _`#772`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/772
+.. _`#798`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/798
+.. _`#800`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/800
+.. _`#890`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/890
+.. _`#983`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/983
+.. _`#990`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/990
+.. _`#1055`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1055
+.. _`#1074`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1074
+.. _`#1108`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1108
+.. _`#1155`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1155
+.. _`#1170`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1170
+.. _`#1191`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1191
+.. _`#1127`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1127
+.. _`#1129`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1129
+.. _`#1131`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1131
+.. _`#1166`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1166
+.. _`#1175`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1175
+
+Release 1.7.1 (2010-07-18)
+--------------------------
+
+Bugfixes and Improvements
+'''''''''''''''''''''''''
+
+- Fix bug in which uploader could fail with AssertionFailure or report
+  that it had achieved servers-of-happiness when it hadn't. (`#1118`_)
+- Fix bug in which servers could get into a state where they would
+  refuse to accept shares of a certain file (`#1117`_)
+- Add init scripts for managing the gateway server on Debian/Ubuntu
+  (`#961`_)
+- Fix bug where server version number was always 0 on the welcome page
+  (`#1067`_)
+- Add new command-line command "tahoe unlink" as a synonym for "tahoe
+  rm" (`#776`_)
+- The FTP frontend now encrypts its temporary files, protecting their
+  contents from an attacker who is able to read the disk. (`#1083`_)
+- Fix IP address detection on FreeBSD 7, 8, and 9 (`#1098`_)
+- Fix minor layout issue in the Web User Interface with Internet
+  Explorer (`#1097`_)
+- Fix rarely-encountered incompatibility between Twisted logging
+  utility and the new unicode support added in v1.7.0 (`#1099`_)
+- Forward-compatibility improvements for non-ASCII caps (`#1051`_)
+
+Code improvements
+'''''''''''''''''
+
+- Simplify and tidy-up directories, unicode support, test code
+  (`#923`_, `#967`_, `#1072`_)
+
+.. _`#776`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/776
+.. _`#923`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/923
+.. _`#961`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/961
+.. _`#967`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/967
+.. _`#1051`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1051
+.. _`#1067`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1067
+.. _`#1072`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1072
+.. _`#1083`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1083
+.. _`#1097`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1097
+.. _`#1098`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1098
+.. _`#1099`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1099
+.. _`#1117`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1117
+.. _`#1118`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1118
+
+
+Release 1.7.0 (2010-06-18)
+--------------------------
+
+New Features
+''''''''''''
+
+- SFTP support (`#1037`_)
+  Your Tahoe-LAFS gateway now acts like a full-fledged SFTP server. It
+  has been tested with sshfs to provide a virtual filesystem in Linux.
+  Many users have asked for this feature.  We hope that it serves them
+  well! See the `FTP-and-SFTP.rst`_ document to get
+  started.
+- support for non-ASCII character encodings (`#534`_)
+  Tahoe-LAFS now correctly handles filenames containing non-ASCII
+  characters on all supported platforms:
+
+ - when reading files in from the local filesystem (such as when you
+   run "tahoe backup" to back up your local files to a Tahoe-LAFS
+   grid);
+ - when writing files out to the local filesystem (such as when you
+   run "tahoe cp -r" to recursively copy files out of a Tahoe-LAFS
+   grid);
+ - when displaying filenames to the terminal (such as when you run
+   "tahoe ls"), subject to limitations of the terminal and locale;
+ - when parsing command-line arguments, except on Windows.
+
+- Servers of Happiness (`#778`_)
+  Tahoe-LAFS now measures during immutable file upload to see how well
+  distributed it is across multiple servers. It aborts the upload if
+  the pieces of the file are not sufficiently well-distributed.
+  This behavior is controlled by a configuration parameter called
+  "servers of happiness". With the default settings for its erasure
+  coding, Tahoe-LAFS generates 10 shares for each file, such that any
+  3 of those shares are sufficient to recover the file. The default
+  value of "servers of happiness" is 7, which means that Tahoe-LAFS
+  will guarantee that there are at least 7 servers holding some of the
+  shares, such that any 3 of those servers can completely recover your
+  file.  The new upload code also distributes the shares better than the
+  previous version in some cases and takes better advantage of
+  pre-existing shares (when a file has already been previously
+  uploaded). See the `architecture.rst`_ document [3] for details.
+
+Bugfixes and Improvements
+'''''''''''''''''''''''''
+
+- Premature abort of upload if some shares were already present and
+  some servers fail. (`#608`_)
+- python ./setup.py install -- can't create or remove files in install
+  directory. (`#803`_)
+- Network failure => internal TypeError. (`#902`_)
+- Install of Tahoe on CentOS 5.4. (`#933`_)
+- CLI option --node-url now supports https url. (`#1028`_)
+- HTML/CSS template files were not correctly installed under
+  Windows. (`#1033`_)
+- MetadataSetter does not enforce restriction on setting "tahoe"
+  subkeys.  (`#1034`_)
+- ImportError: No module named
+  setuptools_darcs.setuptools_darcs. (`#1054`_)
+- Renamed Title in xhtml files. (`#1062`_)
+- Increase Python version dependency to 2.4.4, to avoid a critical
+  CPython security bug. (`#1066`_)
+- Typo correction for the munin plugin tahoe_storagespace. (`#968`_)
+- Fix warnings found by pylint. (`#973`_)
+- Changing format of some documentation files. (`#1027`_)
+- the misc/ directory was tied up. (`#1068`_)
+- The 'ctime' and 'mtime' metadata fields are no longer written except
+  by "tahoe backup". (`#924`_)
+- Unicode filenames in Tahoe-LAFS directories are normalized so that
+  names that differ only in how accents are encoded are treated as the
+  same. (`#1076`_)
+- Various small improvements to documentation. (`#937`_, `#911`_,
+  `#1024`_, `#1082`_)
+
+Removals
+''''''''
+
+- The 'tahoe debug consolidate' subcommand (for converting old
+  allmydata Windows client backups to a newer format) has been
+  removed.
+
+Dependency Updates
+''''''''''''''''''
+
+- the Python version dependency is raised to 2.4.4 in some cases
+  (2.4.3 for Redhat-based Linux distributions, 2.4.2 for UCS-2 builds)
+  (`#1066`_)
+- pycrypto >= 2.0.1
+- pyasn1 >= 0.0.8a
+- mock (only required by unit tests)
+
+.. _`#534`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/534
+.. _`#608`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/608
+.. _`#778`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/778
+.. _`#803`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/803
+.. _`#902`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/902
+.. _`#911`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/911
+.. _`#924`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/924
+.. _`#937`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/937
+.. _`#933`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/933
+.. _`#968`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/968
+.. _`#973`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/973
+.. _`#1024`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1024
+.. _`#1027`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1027
+.. _`#1028`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1028
+.. _`#1033`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1033
+.. _`#1034`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1034
+.. _`#1037`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1037
+.. _`#1054`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1054
+.. _`#1062`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1062
+.. _`#1066`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1066
+.. _`#1068`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1068
+.. _`#1076`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1076
+.. _`#1082`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1082
+.. _architecture.rst: docs/architecture.rst
+.. _FTP-and-SFTP.rst: docs/frontends/FTP-and-SFTP.rst
+
+Release 1.6.1 (2010-02-27)
+--------------------------
+
+Bugfixes
+''''''''
+
+- Correct handling of Small Immutable Directories
+
+  Immutable directories can now be deep-checked and listed in the web
+  UI in all cases. (In v1.6.0, some operations, such as deep-check, on
+  a directory graph that included very small immutable directories,
+  would result in an exception causing the whole operation to abort.)
+  (`#948`_)
+
+Usability Improvements
+''''''''''''''''''''''
+
+- Improved user interface messages and error reporting. (`#681`_,
+  `#837`_, `#939`_)
+- The timeouts for operation handles have been greatly increased, so
+  that you can view the results of an operation up to 4 days after it
+  has completed. After viewing them for the first time, the results
+  are retained for a further day. (`#577`_)
+
+Release 1.6.0 (2010-02-01)
+--------------------------
+
+New Features
+''''''''''''
+
+- Immutable Directories
+
+  Tahoe-LAFS can now create and handle immutable
+  directories. (`#607`_, `#833`_, `#931`_) These are read just like
+  normal directories, but are "deep-immutable", meaning that all their
+  children (and everything reachable from those children) must be
+  immutable objects (i.e. immutable or literal files, and other
+  immutable directories).
+
+  These directories must be created in a single webapi call that
+  provides all of the children at once. (Since they cannot be changed
+  after creation, the usual create/add/add sequence cannot be used.)
+  They have URIs that start with "URI:DIR2-CHK:" or "URI:DIR2-LIT:",
+  and are described on the human-facing web interface (aka the "WUI")
+  with a "DIR-IMM" abbreviation (as opposed to "DIR" for the usual
+  read-write directories and "DIR-RO" for read-only directories).
+
+  Tahoe-LAFS releases before 1.6.0 cannot read the contents of an
+  immutable directory. 1.5.0 will tolerate their presence in a
+  directory listing (and display it as "unknown"). 1.4.1 and earlier
+  cannot tolerate them: a DIR-IMM child in any directory will prevent
+  the listing of that directory.
+
+  Immutable directories are repairable, just like normal immutable
+  files.
+
+  The webapi "POST t=mkdir-immutable" call is used to create immutable
+  directories. See `webapi.rst`_ for details.
+
+- "tahoe backup" now creates immutable directories, backupdb has
+  dircache
+
+  The "tahoe backup" command has been enhanced to create immutable
+  directories (in previous releases, it created read-only mutable
+  directories) (`#828`_). This is significantly faster, since it does
+  not need to create an RSA keypair for each new directory. Also
+  "DIR-IMM" immutable directories are repairable, unlike "DIR-RO"
+  read-only mutable directories at present. (A future Tahoe-LAFS
+  release should also be able to repair DIR-RO.)
+
+  In addition, the backupdb (used by "tahoe backup" to remember what
+  it has already copied) has been enhanced to store information about
+  existing immutable directories. This allows it to re-use directories
+  that have moved but still contain identical contents, or that have
+  been deleted and later replaced. (The 1.5.0 "tahoe backup" command
+  could only re-use directories that were in the same place as they
+  were in the immediately previous backup.)  With this change, the
+  backup process no longer needs to read the previous snapshot out of
+  the Tahoe-LAFS grid, reducing the network load
+  considerably. (`#606`_)
+
+  A "null backup" (in which nothing has changed since the previous
+  backup) will require only two Tahoe-side operations: one to add an
+  Archives/$TIMESTAMP entry, and a second to update the Latest/
+  link. On the local disk side, it will readdir() all your local
+  directories and stat() all your local files.
+
+  If you've been using "tahoe backup" for a while, you will notice
+  that your first use of it after upgrading to 1.6.0 may take a long
+  time: it must create proper immutable versions of all the old
+  read-only mutable directories. This process won't take as long as
+  the initial backup (where all the file contents had to be uploaded
+  too): it will require time proportional to the number and size of
+  your directories. After this initial pass, all subsequent passes
+  should take a tiny fraction of the time.
+
+  As noted above, Tahoe-LAFS versions earlier than 1.5.0 cannot list a
+  directory containing an immutable subdirectory. Tahoe-LAFS versions
+  earlier than 1.6.0 cannot read the contents of an immutable
+  directory.
+
+  The "tahoe backup" command has been improved to skip over unreadable
+  objects (like device files, named pipes, and files with permissions
+  that prevent the command from reading their contents), instead of
+  throwing an exception and terminating the backup process. It also
+  skips over symlinks, because these cannot be represented faithfully
+  in the Tahoe-side filesystem. A warning message will be emitted each
+  time something is skipped. (`#729`_, `#850`_, `#641`_)
+
+- "create-node" command added, "create-client" now implies
+  --no-storage
+
+  The basic idea behind Tahoe-LAFS's client+server and client-only
+  processes is that you are creating a general-purpose Tahoe-LAFS
+  "node" process, which has several components that can be
+  activated. Storage service is one of these optional components, as
+  is the Helper, FTP server, and SFTP server. Web gateway
+  functionality is nominally on this list, but it is always active; a
+  future release will make it optional. There are three special
+  purpose servers that can't currently be run as a component in a
+  node: introducer, key-generator, and stats-gatherer.
+
+  So now "tahoe create-node" will create a Tahoe-LAFS node process,
+  and after creation you can edit its tahoe.cfg to enable or disable
+  the desired services. It is a more general-purpose replacement for
+  "tahoe create-client".  The default configuration has storage
+  service enabled. For convenience, the "--no-storage" argument makes
+  a tahoe.cfg file that disables storage service. (`#760`_)
+
+  "tahoe create-client" has been changed to create a Tahoe-LAFS node
+  without a storage service. It is equivalent to "tahoe create-node
+  --no-storage". This helps to reduce the confusion surrounding the
+  use of a command with "client" in its name to create a storage
+  *server*. Use "tahoe create-client" to create a purely client-side
+  node. If you want to offer storage to the grid, use "tahoe
+  create-node" instead.
+
+  In the future, other services will be added to the node, and they
+  will be controlled through options in tahoe.cfg . The most important
+  of these services may get additional --enable-XYZ or --disable-XYZ
+  arguments to "tahoe create-node".
+
+- Performance Improvements
+
+  Download of immutable files begins as soon as the downloader has
+  located the K necessary shares (`#928`_, `#287`_). In both the
+  previous and current releases, a downloader will first issue queries
+  to all storage servers on the grid to locate shares before it begins
+  downloading the shares. In previous releases of Tahoe-LAFS, download
+  would not begin until all storage servers on the grid had replied to
+  the query, at which point K shares would be chosen for download from
+  among the shares that were located. In this release, download begins
+  as soon as any K shares are located. This means that downloads start
+  sooner, which is particularly important if there is a server on the
+  grid that is extremely slow or even hung in such a way that it will
+  never respond. In previous releases such a server would have a
+  negative impact on all downloads from that grid. In this release,
+  such a server will have no impact on downloads, as long as K shares
+  can be found on other, quicker, servers.  This also means that
+  downloads now use the "best-alacrity" servers that they talk to, as
+  measured by how quickly the servers reply to the initial query. This
+  might cause downloads to go faster, especially on grids with
+  heterogeneous servers or geographical dispersion.
+
+Minor Changes
+'''''''''''''
+
+- The webapi acquired a new "t=mkdir-with-children" command, to create
+  and populate a directory in a single call. This is significantly
+  faster than using separate "t=mkdir" and "t=set-children" operations
+  (it uses one gateway-to-grid roundtrip, instead of three or
+  four). (`#533`_)
+
+- The t=set-children (note the hyphen) operation is now documented in
+  webapi.rst, and is the new preferred spelling of the
+  old t=set_children (with an underscore). The underscore version
+  remains for backwards compatibility. (`#381`_, `#927`_)
+
+- The tracebacks produced by errors in CLI tools should now be in
+  plain text, instead of HTML (which is unreadable outside of a
+  browser). (`#646`_)
+
+- The [storage]reserved_space configuration knob (which causes the
+  storage server to refuse shares when available disk space drops
+  below a threshold) should work on Windows now, not just
+  UNIX. (`#637`_)
+
+- "tahoe cp" should now exit with status "1" if it cannot figure out a
+  suitable target filename, such as when you copy from a bare
+  filecap. (`#761`_)
+
+- "tahoe get" no longer creates a zero-length file upon
+  error. (`#121`_)
+
+- "tahoe ls" can now list single files. (`#457`_)
+
+- "tahoe deep-check --repair" should tolerate repair failures now,
+  instead of halting traversal. (`#874`_, `#786`_)
+
+- "tahoe create-alias" no longer corrupts the aliases file if it had
+  previously been edited to have no trailing newline. (`#741`_)
+
+- Many small packaging improvements were made to facilitate the
+  "tahoe-lafs" package being included in Ubuntu. Several mac/win32
+  binary libraries were removed, some figleaf code-coverage files were
+  removed, a bundled copy of darcsver-1.2.1 was removed, and
+  additional licensing text was added.
+
+- Several DeprecationWarnings for python2.6 were silenced. (`#859`_)
+
+- The checker --add-lease option would sometimes fail for shares
+  stored on old (Tahoe v1.2.0) servers. (`#875`_)
+
+- The documentation for installing on Windows (docs/quickstart.rst)
+  has been improved. (`#773`_)
+
+For other changes not mentioned here, see
+<https://tahoe-lafs.org/trac/tahoe-lafs/query?milestone=1.6.0&keywords=!~news-done>.
+To include the tickets mentioned above, go to
+<https://tahoe-lafs.org/trac/tahoe-lafs/query?milestone=1.6.0>.
+
+.. _`#121`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/121
+.. _`#287`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/287
+.. _`#381`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/381
+.. _`#457`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/457
+.. _`#533`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/533
+.. _`#577`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/577
+.. _`#606`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/606
+.. _`#607`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/607
+.. _`#637`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/637
+.. _`#641`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/641
+.. _`#646`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/646
+.. _`#681`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/681
+.. _`#729`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/729
+.. _`#741`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/741
+.. _`#760`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/760
+.. _`#761`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/761
+.. _`#768`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/768
+.. _`#773`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/773
+.. _`#786`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/786
+.. _`#828`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/828
+.. _`#833`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/833
+.. _`#859`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/859
+.. _`#874`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/874
+.. _`#875`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/875
+.. _`#931`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/931
+.. _`#837`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/837
+.. _`#850`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/850
+.. _`#927`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/927
+.. _`#928`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/928
+.. _`#939`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/939
+.. _`#948`: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/948
+.. _webapi.rst: docs/frontends/webapi.rst
+
+Release 1.5.0 (2009-08-01)
+--------------------------
+
+Improvements
+''''''''''''
+
+- Uploads of immutable files now use pipelined writes, improving
+  upload speed slightly (10%) over high-latency connections. (`#392`_)
+
+- Processing large directories has been sped up, by removing a O(N^2)
+  algorithm from the dirnode decoding path and retaining unmodified
+  encrypted entries.  (`#750`_, `#752`_)
+
+- The human-facing web interface (aka the "WUI") received a
+  significant CSS makeover by Kevin Reid, making it much prettier and
+  easier to read. The WUI "check" and "deep-check" forms now include a
+  "Renew Lease" checkbox, mirroring the CLI --add-lease option, so
+  leases can be added or renewed from the web interface.
+
+- The CLI "tahoe mv" command now refuses to overwrite
+  directories. (`#705`_)
+
+- The CLI "tahoe webopen" command, when run without arguments, will
+  now bring up the "Welcome Page" (node status and mkdir/upload
+  forms).
+
+- The 3.5MB limit on mutable files was removed, so it should be
+  possible to upload arbitrarily-sized mutable files. Note, however,
+  that the data format and algorithm remains the same, so using
+  mutable files still requires bandwidth, computation, and RAM in
+  proportion to the size of the mutable file.  (`#694`_)
+
+- This version of Tahoe-LAFS will tolerate directory entries that
+  contain filecap formats which it does not recognize: files and
+  directories from the future.  This should improve the user
+  experience (for 1.5.0 users) when we add new cap formats in the
+  future. Previous versions would fail badly, preventing the user from
+  seeing or editing anything else in those directories. These
+  unrecognized objects can be renamed and deleted, but obviously not
+  read or written. Also they cannot generally be copied. (`#683`_)
+
+Bugfixes
+''''''''
+
+- deep-check-and-repair now tolerates read-only directories, such as
+  the ones produced by the "tahoe backup" CLI command. Read-only
+  directories and mutable files are checked, but not
+  repaired. Previous versions threw an exception when attempting the
+  repair and failed to process the remaining contents. We cannot yet
+  repair these read-only objects, but at least this version allows the
+  rest of the check+repair to proceed. (`#625`_)
+
+- A bug in 1.4.1 which caused a server to be listed multiple times
+  (and frequently broke all connections to that server) was
+  fixed. (`#653`_)
+
+- The plaintext-hashing code was removed from the Helper interface,
+  removing the Helper's ability to mount a
+  partial-information-guessing attack. (`#722`_)
+
+Platform/packaging changes
+''''''''''''''''''''''''''
+
+- Tahoe-LAFS now runs on NetBSD, OpenBSD, ArchLinux, and NixOS, and on
+  an embedded system based on an ARM CPU running at 266 MHz.
+
+- Unit test timeouts have been raised to allow the tests to complete
+  on extremely slow platforms like embedded ARM-based NAS boxes, which
+  may take several hours to run the test suite. An ARM-specific
+  data-corrupting bug in an older version of Crypto++ (5.5.2) was
+  identified: ARM-users are encouraged to use recent
+  Crypto++/pycryptopp which avoids this problem.
+
+- Tahoe-LAFS now requires a SQLite library, either the sqlite3 that
+  comes built-in with python2.5/2.6, or the add-on pysqlite2 if you're
+  using python2.4. In the previous release, this was only needed for
+  the "tahoe backup" command: now it is mandatory.
+
+- Several minor documentation updates were made.
+
+- To help get Tahoe-LAFS into Linux distributions like Fedora and
+  Debian, packaging improvements are being made in both Tahoe-LAFS and
+  related libraries like pycryptopp and zfec.
+
+- The Crypto++ library included in the pycryptopp package has been
+  upgraded to version 5.6.0 of Crypto++, which includes a more
+  efficient implementation of SHA-256 in assembly for x86 or amd64
+  architectures.
+
+dependency updates
+''''''''''''''''''
+
+- foolscap-0.4.1
+- no python-2.4.0 or 2.4.1 (2.4.2 is good) (they contained a bug in base64.b32decode)
+- avoid python-2.6 on windows with mingw: compiler issues
+- python2.4 requires pysqlite2 (2.5,2.6 does not)
+- no python-3.x
+- pycryptopp-0.5.15
+
+.. _#392: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/392
+.. _#625: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/625
+.. _#653: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/653
+.. _#683: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/683
+.. _#694: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/694
+.. _#705: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/705
+.. _#722: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/722
+.. _#750: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/750
+.. _#752: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/752
+
+Release 1.4.1 (2009-04-13)
+--------------------------
+
+Garbage Collection
+''''''''''''''''''
+
+- The big feature for this release is the implementation of garbage
+  collection, allowing Tahoe storage servers to delete shares for old
+  deleted files. When enabled, this uses a "mark and sweep" process:
+  clients are responsible for updating the leases on their shares
+  (generally by running "tahoe deep-check --add-lease"), and servers
+  are allowed to delete any share which does not have an up-to-date
+  lease. The process is described in detail in
+  `garbage-collection.rst`_.
+
+  The server must be configured to enable garbage-collection, by
+  adding directives to the [storage] section that define an age limit
+  for shares. The default configuration will not delete any shares.
+
+  Both servers and clients should be upgraded to this release to make
+  the garbage-collection as pleasant as possible. 1.2.0 servers have
+  code to perform the update-lease operation but it suffers from a
+  fatal bug, while 1.3.0 servers have update-lease but will return an
+  exception for unknown storage indices, causing clients to emit an
+  Incident for each exception, slowing the add-lease process down to a
+  crawl. 1.1.0 servers did not have the add-lease operation at all.
+
+Security/Usability Problems Fixed
+'''''''''''''''''''''''''''''''''
+
+- A super-linear algorithm in the Merkle Tree code was fixed, which
+  previously caused e.g. download of a 10GB file to take several hours
+  before the first byte of plaintext could be produced. The new
+  "alacrity" is about 2 minutes. A future release should reduce this
+  to a few seconds by fixing ticket `#442`_.
+
+- The previous version permitted a small timing attack (due to our use
+  of strcmp) against the write-enabler and lease-renewal/cancel
+  secrets. An attacker who could measure response-time variations of
+  approximatly 3ns against a very noisy background time of about 15ms
+  might be able to guess these secrets. We do not believe this attack
+  was actually feasible. This release closes the attack by first
+  hashing the two strings to be compared with a random secret.
+
+webapi changes
+''''''''''''''
+
+- In most cases, HTML tracebacks will only be sent if an "Accept:
+  text/html" header was provided with the HTTP request. This will
+  generally cause browsers to get an HTMLized traceback but send
+  regular text/plain tracebacks to non-browsers (like the CLI
+  clients). More errors have been mapped to useful HTTP error codes.
+
+- The streaming webapi operations (deep-check and manifest) now have a
+  way to indicate errors (an output line that starts with "ERROR"
+  instead of being legal JSON). See `webapi.rst`_ for
+  details.
+
+- The storage server now has its own status page (at /storage), linked
+  from the Welcome page. This page shows progress and results of the
+  two new share-crawlers: one which merely counts shares (to give an
+  estimate of how many files/directories are being stored in the
+  grid), the other examines leases and reports how much space would be
+  freed if GC were enabled. The page also shows how much disk space is
+  present, used, reserved, and available for the Tahoe server, and
+  whether the server is currently running in "read-write" mode or
+  "read-only" mode.
+
+- When a directory node cannot be read (perhaps because of insufficent
+  shares), a minimal webapi page is created so that the "more-info"
+  links (including a Check/Repair operation) will still be accessible.
+
+- A new "reliability" page was added, with the beginnings of work on a
+  statistical loss model. You can tell this page how many servers you
+  are using and their independent failure probabilities, and it will
+  tell you the likelihood that an arbitrary file will survive each
+  repair period. The "numpy" package must be installed to access this
+  page. A partial paper, written by Shawn Willden, has been added to
+  docs/proposed/lossmodel.lyx .
+
+CLI changes
+'''''''''''
+
+- "tahoe check" and "tahoe deep-check" now accept an "--add-lease"
+  argument, to update a lease on all shares. This is the "mark" side
+  of garbage collection.
+
+- In many cases, CLI error messages have been improved: the ugly
+  HTMLized traceback has been replaced by a normal python traceback.
+
+- "tahoe deep-check" and "tahoe manifest" now have better error
+  reporting.  "tahoe cp" is now non-verbose by default.
+
+- "tahoe backup" now accepts several "--exclude" arguments, to ignore
+  certain files (like editor temporary files and version-control
+  metadata) during backup.
+
+- On windows, the CLI now accepts local paths like "c:\dir\file.txt",
+  which previously was interpreted as a Tahoe path using a "c:" alias.
+
+- The "tahoe restart" command now uses "--force" by default (meaning
+  it will start a node even if it didn't look like there was one
+  already running).
+
+- The "tahoe debug consolidate" command was added. This takes a series
+  of independent timestamped snapshot directories (such as those
+  created by the allmydata.com windows backup program, or a series of
+  "tahoe cp -r" commands) and creates new snapshots that used shared
+  read-only directories whenever possible (like the output of "tahoe
+  backup"). In the most common case (when the snapshots are fairly
+  similar), the result will use significantly fewer directories than
+  the original, allowing "deep-check" and similar tools to run much
+  faster. In some cases, the speedup can be an order of magnitude or
+  more.  This tool is still somewhat experimental, and only needs to
+  be run on large backups produced by something other than "tahoe
+  backup", so it was placed under the "debug" category.
+
+- "tahoe cp -r --caps-only tahoe:dir localdir" is a diagnostic tool
+  which, instead of copying the full contents of files into the local
+  directory, merely copies their filecaps. This can be used to verify
+  the results of a "consolidation" operation.
+
+other fixes
+'''''''''''
+
+- The codebase no longer rauses RuntimeError as a kind of
+  assert(). Specific exception classes were created for each previous
+  instance of RuntimeError.
+
+ -Many unit tests were changed to use a non-network test harness,
+  speeding them up considerably.
+
+- Deep-traversal operations (manifest and deep-check) now walk
+  individual directories in alphabetical order. Occasional turn breaks
+  are inserted to prevent a stack overflow when traversing directories
+  with hundreds of entries.
+
+- The experimental SFTP server had its path-handling logic changed
+  slightly, to accomodate more SFTP clients, although there are still
+  issues (`#645`_).
+
+.. _#442: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/442
+.. _#645: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/645
+.. _garbage-collection.rst: docs/garbage-collection.rst
+
+Release 1.3.0 (2009-02-13)
+--------------------------
+
+Checker/Verifier/Repairer
+'''''''''''''''''''''''''
+
+- The primary focus of this release has been writing a checker /
+  verifier / repairer for files and directories.  "Checking" is the
+  act of asking storage servers whether they have a share for the
+  given file or directory: if there are not enough shares available,
+  the file or directory will be unrecoverable. "Verifying" is the act
+  of downloading and cryptographically asserting that the server's
+  share is undamaged: it requires more work (bandwidth and CPU) than
+  checking, but can catch problems that simple checking
+  cannot. "Repair" is the act of replacing missing or damaged shares
+  with new ones.
+
+- This release includes a full checker, a partial verifier, and a
+  partial repairer. The repairer is able to handle missing shares: new
+  shares are generated and uploaded to make up for the missing
+  ones. This is currently the best application of the repairer: to
+  replace shares that were lost because of server departure or
+  permanent drive failure.
+
+- The repairer in this release is somewhat able to handle corrupted
+  shares. The limitations are:
+
+ - Immutable verifier is incomplete: not all shares are used, and not
+   all fields of those shares are verified. Therefore the immutable
+   verifier has only a moderate chance of detecting corrupted shares.
+ - The mutable verifier is mostly complete: all shares are examined,
+   and most fields of the shares are validated.
+ - The storage server protocol offers no way for the repairer to
+   replace or delete immutable shares. If corruption is detected, the
+   repairer will upload replacement shares to other servers, but the
+   corrupted shares will be left in place.
+ - read-only directories and read-only mutable files must be repaired
+   by someone who holds the write-cap: the read-cap is
+   insufficient. Moreover, the deep-check-and-repair operation will
+   halt with an error if it attempts to repair one of these read-only
+   objects.
+ - Some forms of corruption can cause both download and repair
+   operations to fail. A future release will fix this, since download
+   should be tolerant of any corruption as long as there are at least
+   'k' valid shares, and repair should be able to fix any file that is
+   downloadable.
+
+- If the downloader, verifier, or repairer detects share corruption,
+  the servers which provided the bad shares will be notified (via a
+  file placed in the BASEDIR/storage/corruption-advisories directory)
+  so their operators can manually delete the corrupted shares and
+  investigate the problem. In addition, the "incident gatherer"
+  mechanism will automatically report share corruption to an incident
+  gatherer service, if one is configured. Note that corrupted shares
+  indicate hardware failures, serious software bugs, or malice on the
+  part of the storage server operator, so a corrupted share should be
+  considered highly unusual.
+
+- By periodically checking/repairing all files and directories,
+  objects in the Tahoe filesystem remain resistant to recoverability
+  failures due to missing and/or broken servers.
+
+- This release includes a wapi mechanism to initiate checks on
+  individual files and directories (with or without verification, and
+  with or without automatic repair). A related mechanism is used to
+  initiate a "deep-check" on a directory: recursively traversing the
+  directory and its children, checking (and/or verifying/repairing)
+  everything underneath. Both mechanisms can be run with an
+  "output=JSON" argument, to obtain machine-readable check/repair
+  status results. These results include a copy of the filesystem
+  statistics from the "deep-stats" operation (including total number
+  of files, size histogram, etc). If repair is possible, a "Repair"
+  button will appear on the results page.
+
+- The client web interface now features some extra buttons to initiate
+  check and deep-check operations. When these operations finish, they
+  display a results page that summarizes any problems that were
+  encountered. All long-running deep-traversal operations, including
+  deep-check, use a start-and-poll mechanism, to avoid depending upon
+  a single long-lived HTTP connection. `webapi.rst`_ has
+  details.
+
+Efficient Backup
+''''''''''''''''
+
+- The "tahoe backup" command is new in this release, which creates
+  efficient versioned backups of a local directory. Given a local
+  pathname and a target Tahoe directory, this will create a read-only
+  snapshot of the local directory in $target/Archives/$timestamp. It
+  will also create $target/Latest, which is a reference to the latest
+  such snapshot. Each time you run "tahoe backup" with the same source
+  and target, a new $timestamp snapshot will be added. These snapshots
+  will share directories that have not changed since the last backup,
+  to speed up the process and minimize storage requirements. In
+  addition, a small database is used to keep track of which local
+  files have been uploaded already, to avoid uploading them a second
+  time. This drastically reduces the work needed to do a "null backup"
+  (when nothing has changed locally), making "tahoe backup' suitable
+  to run from a daily cronjob.
+
+  Note that the "tahoe backup" CLI command must be used in conjunction
+  with a 1.3.0-or-newer Tahoe client node; there was a bug in the
+  1.2.0 webapi implementation that would prevent the last step (create
+  $target/Latest) from working.
+
+Large Files
+'''''''''''
+
+- The 12GiB (approximate) immutable-file-size limitation is
+  lifted. This release knows how to handle so-called "v2 immutable
+  shares", which permit immutable files of up to about 18 EiB (about
+  3*10^14). These v2 shares are created if the file to be uploaded is
+  too large to fit into v1 shares. v1 shares are created if the file
+  is small enough to fit into them, so that files created with
+  tahoe-1.3.0 can still be read by earlier versions if they are not
+  too large. Note that storage servers also had to be changed to
+  support larger files, and this release is the first release in which
+  they are able to do that. Clients will detect which servers are
+  capable of supporting large files on upload and will not attempt to
+  upload shares of a large file to a server which doesn't support it.
+
+FTP/SFTP Server
+'''''''''''''''
+
+- Tahoe now includes experimental FTP and SFTP servers. When
+  configured with a suitable method to translate username+password
+  into a root directory cap, it provides simple access to the virtual
+  filesystem. Remember that FTP is completely unencrypted: passwords,
+  filenames, and file contents are all sent over the wire in
+  cleartext, so FTP should only be used on a local (127.0.0.1)
+  connection. This feature is still in development: there are no unit
+  tests yet, and behavior with respect to Unicode filenames is
+  uncertain. Please see `FTP-and-SFTP.rst`_ for
+  configuration details. (`#512`_, `#531`_)
+
+CLI Changes
+'''''''''''
+
+- This release adds the 'tahoe create-alias' command, which is a
+  combination of 'tahoe mkdir' and 'tahoe add-alias'. This also allows
+  you to start using a new tahoe directory without exposing its URI in
+  the argv list, which is publicly visible (through the process table)
+  on most unix systems.  Thanks to Kevin Reid for bringing this issue
+  to our attention.
+
+- The single-argument form of "tahoe put" was changed to create an
+  unlinked file. I.e. "tahoe put bar.txt" will take the contents of a
+  local "bar.txt" file, upload them to the grid, and print the
+  resulting read-cap; the file will not be attached to any
+  directories. This seemed a bit more useful than the previous
+  behavior (copy stdin, upload to the grid, attach the resulting file
+  into your default tahoe: alias in a child named 'bar.txt').
+
+- "tahoe put" was also fixed to handle mutable files correctly: "tahoe
+  put bar.txt URI:SSK:..." will read the contents of the local bar.txt
+  and use them to replace the contents of the given mutable file.
+
+- The "tahoe webopen" command was modified to accept aliases. This
+  means "tahoe webopen tahoe:" will cause your web browser to open to
+  a "wui" page that gives access to the directory associated with the
+  default "tahoe:" alias. It should also accept leading slashes, like
+  "tahoe webopen tahoe:/stuff".
+
+- Many esoteric debugging commands were moved down into a "debug"
+  subcommand:
+
+ - tahoe debug dump-cap
+ - tahoe debug dump-share
+ - tahoe debug find-shares
+ - tahoe debug catalog-shares
+ - tahoe debug corrupt-share
+
+   The last command ("tahoe debug corrupt-share") flips a random bit
+   of the given local sharefile. This is used to test the file
+   verifying/repairing code, and obviously should not be used on user
+   data.
+
+The cli might not correctly handle arguments which contain non-ascii
+characters in Tahoe v1.3 (although depending on your platform it
+might, especially if your platform can be configured to pass such
+characters on the command-line in utf-8 encoding).  See
+https://tahoe-lafs.org/trac/tahoe-lafs/ticket/565 for details.
+
+Web changes
+'''''''''''
+
+- The "default webapi port", used when creating a new client node (and
+  in the getting-started documentation), was changed from 8123 to
+  3456, to reduce confusion when Tahoe accessed through a Firefox
+  browser on which the "Torbutton" extension has been installed. Port
+  8123 is occasionally used as a Tor control port, so Torbutton adds
+  8123 to Firefox's list of "banned ports" to avoid CSRF attacks
+  against Tor. Once 8123 is banned, it is difficult to diagnose why
+  you can no longer reach a Tahoe node, so the Tahoe default was
+  changed. Note that 3456 is reserved by IANA for the "vat" protocol,
+  but there are argueably more Torbutton+Tahoe users than vat users
+  these days. Note that this will only affect newly-created client
+  nodes. Pre-existing client nodes, created by earlier versions of
+  tahoe, may still be listening on 8123.
+
+- All deep-traversal operations (start-manifest, start-deep-size,
+  start-deep-stats, start-deep-check) now use a start-and-poll
+  approach, instead of using a single (fragile) long-running
+  synchronous HTTP connection. All these "start-" operations use POST
+  instead of GET. The old "GET manifest", "GET deep-size", and "POST
+  deep-check" operations have been removed.
+
+- The new "POST start-manifest" operation, when it finally completes,
+  results in a table of (path,cap), instead of the list of verifycaps
+  produced by the old "GET manifest". The table is available in
+  several formats: use output=html, output=text, or output=json to
+  choose one. The JSON output also includes stats, and a list of
+  verifycaps and storage-index strings. The "return_to=" and
+  "when_done=" arguments have been removed from the t=check and
+  deep-check operations.
+
+- The top-level status page (/status) now has a machine-readable form,
+  via "/status/?t=json". This includes information about the
+  currently-active uploads and downloads, which may be useful for
+  frontends that wish to display progress information. There is no
+  easy way to correlate the activities displayed here with recent wapi
+  requests, however.
+
+- Any files in BASEDIR/public_html/ (configurable) will be served in
+  response to requests in the /static/ portion of the URL space. This
+  will simplify the deployment of javascript-based frontends that can
+  still access wapi calls by conforming to the (regrettable)
+  "same-origin policy".
+
+- The welcome page now has a "Report Incident" button, which is tied
+  into the "Incident Gatherer" machinery. If the node is attached to
+  an incident gatherer (via log_gatherer.furl), then pushing this
+  button will cause an Incident to be signalled: this means recent log
+  events are aggregated and sent in a bundle to the gatherer. The user
+  can push this button after something strange takes place (and they
+  can provide a short message to go along with it), and the relevant
+  data will be delivered to a centralized incident-gatherer for later
+  processing by operations staff.
+
+- The "HEAD" method should now work correctly, in addition to the
+  usual "GET", "PUT", and "POST" methods. "HEAD" is supposed to return
+  exactly the same headers as "GET" would, but without any of the
+  actual response body data. For mutable files, this now does a brief
+  mapupdate (to figure out the size of the file that would be
+  returned), without actually retrieving the file's contents.
+
+- The "GET" operation on files can now support the HTTP "Range:"
+  header, allowing requests for partial content. This allows certain
+  media players to correctly stream audio and movies out of a Tahoe
+  grid. The current implementation uses a disk-based cache in
+  BASEDIR/private/cache/download , which holds the plaintext of the
+  files being downloaded. Future implementations might not use this
+  cache. GET for immutable files now returns an ETag header.
+
+- Each file and directory now has a "Show More Info" web page, which
+  contains much of the information that was crammed into the directory
+  page before. This includes readonly URIs, storage index strings,
+  object type, buttons to control checking/verifying/repairing, and
+  deep-check/deep-stats buttons (for directories). For mutable files,
+  the "replace contents" upload form has been moved here too. As a
+  result, the directory page is now much simpler and cleaner, and
+  several potentially-misleading links (like t=uri) are now gone.
+
+- Slashes are discouraged in Tahoe file/directory names, since they
+  cause problems when accessing the filesystem through the
+  wapi. However, there are a couple of accidental ways to generate
+  such names. This release tries to make it easier to correct such
+  mistakes by escaping slashes in several places, allowing slashes in
+  the t=info and t=delete commands, and in the source (but not the
+  target) of a t=rename command.
+
+Packaging
+'''''''''
+
+- Tahoe's dependencies have been extended to require the
+  "[secure_connections]" feature from Foolscap, which will cause
+  pyOpenSSL to be required and/or installed. If OpenSSL and its
+  development headers are already installed on your system, this can
+  occur automatically. Tahoe now uses pollreactor (instead of the
+  default selectreactor) to work around a bug between pyOpenSSL and
+  the most recent release of Twisted (8.1.0). This bug only affects
+  unit tests (hang during shutdown), and should not impact regular
+  use.
+
+- The Tahoe source code tarballs now come in two different forms:
+  regular and "sumo". The regular tarball contains just Tahoe, nothing
+  else. When building from the regular tarball, the build process will
+  download any unmet dependencies from the internet (starting with the
+  index at PyPI) so it can build and install them. The "sumo" tarball
+  contains copies of all the libraries that Tahoe requires (foolscap,
+  twisted, zfec, etc), so using the "sumo" tarball should not require
+  any internet access during the build process. This can be useful if
+  you want to build Tahoe while on an airplane, a desert island, or
+  other bandwidth-limited environments.
+
+- Similarly, tahoe-lafs.org now hosts a "tahoe-deps" tarball which
+  contains the latest versions of all these dependencies. This
+  tarball, located at
+  https://tahoe-lafs.org/source/tahoe/deps/tahoe-deps.tar.gz, can be
+  unpacked in the tahoe source tree (or in its parent directory), and
+  the build process should satisfy its downloading needs from it
+  instead of reaching out to PyPI.  This can be useful if you want to
+  build Tahoe from a darcs checkout while on that airplane or desert
+  island.
+
+- Because of the previous two changes ("sumo" tarballs and the
+  "tahoe-deps" bundle), most of the files have been removed from
+  misc/dependencies/ . This brings the regular Tahoe tarball down to
+  2MB (compressed), and the darcs checkout (without history) to about
+  7.6MB. A full darcs checkout will still be fairly large (because of
+  the historical patches which included the dependent libraries), but
+  a 'lazy' one should now be small.
+
+- The default "make" target is now an alias for "setup.py build",
+  which itself is an alias for "setup.py develop --prefix support",
+  with some extra work before and after (see setup.cfg). Most of the
+  complicated platform-dependent code in the Makefile was rewritten in
+  Python and moved into setup.py, simplifying things considerably.
+
+- Likewise, the "make test" target now delegates most of its work to
+  "setup.py test", which takes care of getting PYTHONPATH configured
+  to access the tahoe code (and dependencies) that gets put in
+  support/lib/ by the build_tahoe step. This should allow unit tests
+  to be run even when trial (which is part of Twisted) wasn't already
+  installed (in this case, trial gets installed to support/bin because
+  Twisted is a dependency of Tahoe).
+
+- Tahoe is now compatible with the recently-released Python 2.6 ,
+  although it is recommended to use Tahoe on Python 2.5, on which it
+  has received more thorough testing and deployment.
+
+- Tahoe is now compatible with simplejson-2.0.x . The previous release
+  assumed that simplejson.loads always returned unicode strings, which
+  is no longer the case in 2.0.x .
+
+Grid Management Tools
+'''''''''''''''''''''
+
+- Several tools have been added or updated in the misc/ directory,
+  mostly munin plugins that can be used to monitor a storage grid.
+
+ - The misc/spacetime/ directory contains a "disk watcher" daemon
+   (startable with 'tahoe start'), which can be configured with a set
+   of HTTP URLs (pointing at the wapi '/statistics' page of a bunch of
+   storage servers), and will periodically fetch
+   disk-used/disk-available information from all the servers. It keeps
+   this information in an Axiom database (a sqlite-based library
+   available from divmod.org). The daemon computes time-averaged rates
+   of disk usage, as well as a prediction of how much time is left
+   before the grid is completely full.
+
+ - The misc/munin/ directory contains a new set of munin plugins
+   (tahoe_diskleft, tahoe_diskusage, tahoe_doomsday) which talk to the
+   disk-watcher and provide graphs of its calculations.
+
+ - To support the disk-watcher, the Tahoe statistics component
+   (visible through the wapi at the /statistics/ URL) now includes
+   disk-used and disk-available information. Both are derived through
+   an equivalent of the unix 'df' command (i.e. they ask the kernel
+   for the number of free blocks on the partition that encloses the
+   BASEDIR/storage directory). In the future, the disk-available
+   number will be further influenced by the local storage policy: if
+   that policy says that the server should refuse new shares when less
+   than 5GB is left on the partition, then "disk-available" will
+   report zero even though the kernel sees 5GB remaining.
+
+ - The 'tahoe_overhead' munin plugin interacts with an
+   allmydata.com-specific server which reports the total of the
+   'deep-size' reports for all active user accounts, compares this
+   with the disk-watcher data, to report on overhead percentages. This
+   provides information on how much space could be recovered once
+   Tahoe implements some form of garbage collection.
+
+Configuration Changes: single INI-format tahoe.cfg file
+'''''''''''''''''''''''''''''''''''''''''''''''''''''''
+
+- The Tahoe node is now configured with a single INI-format file,
+  named "tahoe.cfg", in the node's base directory. Most of the
+  previous multiple-separate-files are still read for backwards
+  compatibility (the embedded SSH debug server and the
+  advertised_ip_addresses files are the exceptions), but new
+  directives will only be added to tahoe.cfg . The "tahoe
+  create-client" command will create a tahoe.cfg for you, with sample
+  values commented out. (ticket `#518`_)
+
+- tahoe.cfg now has controls for the foolscap "keepalive" and
+  "disconnect" timeouts (`#521`_).
+
+- tahoe.cfg now has controls for the encoding parameters:
+  "shares.needed" and "shares.total" in the "[client]" section. The
+  default parameters are still 3-of-10.
+
+- The inefficient storage 'sizelimit' control (which established an
+  upper bound on the amount of space that a storage server is allowed
+  to consume) has been replaced by a lightweight 'reserved_space'
+  control (which establishes a lower bound on the amount of remaining
+  space). The storage server will reject all writes that would cause
+  the remaining disk space (as measured by a '/bin/df' equivalent) to
+  drop below this value. The "[storage]reserved_space=" tahoe.cfg
+  parameter controls this setting. (note that this only affects
+  immutable shares: it is an outstanding bug that reserved_space does
+  not prevent the allocation of new mutable shares, nor does it
+  prevent the growth of existing mutable shares).
+
+Other Changes
+'''''''''''''
+
+- Clients now declare which versions of the protocols they
+  support. This is part of a new backwards-compatibility system:
+  https://tahoe-lafs.org/trac/tahoe-lafs/wiki/Versioning .
+
+- The version strings for human inspection (as displayed on the
+  Welcome web page, and included in logs) now includes a platform
+  identifer (frequently including a linux distribution name, processor
+  architecture, etc).
+
+- Several bugs have been fixed, including one that would cause an
+  exception (in the logs) if a wapi download operation was cancelled
+  (by closing the TCP connection, or pushing the "stop" button in a
+  web browser).
+
+- Tahoe now uses Foolscap "Incidents", writing an "incident report"
+  file to logs/incidents/ each time something weird occurs. These
+  reports are available to an "incident gatherer" through the flogtool
+  command. For more details, please see the Foolscap logging
+  documentation. An incident-classifying plugin function is provided
+  in misc/incident-gatherer/classify_tahoe.py .
+
+- If clients detect corruption in shares, they now automatically
+  report it to the server holding that share, if it is new enough to
+  accept the report.  These reports are written to files in
+  BASEDIR/storage/corruption-advisories .
+
+- The 'nickname' setting is now defined to be a UTF-8 -encoded string,
+  allowing non-ascii nicknames.
+
+- The 'tahoe start' command will now accept a --syslog argument and
+  pass it through to twistd, making it easier to launch non-Tahoe
+  nodes (like the cpu-watcher) and have them log to syslogd instead of
+  a local file. This is useful when running a Tahoe node out of a USB
+  flash drive.
+
+- The Mac GUI in src/allmydata/gui/ has been improved.
+
+.. _#512: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/512
+.. _#518: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/518
+.. _#521: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/521
+.. _#531: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/531
+
+Release 1.2.0 (2008-07-21)
+--------------------------
+
+Security
+''''''''
+
+- This release makes the immutable-file "ciphertext hash tree"
+  mandatory.  Previous releases allowed the uploader to decide whether
+  their file would have an integrity check on the ciphertext or not. A
+  malicious uploader could use this to create a readcap that would
+  download as one file or a different one, depending upon which shares
+  the client fetched first, with no errors raised. There are other
+  integrity checks on the shares themselves, preventing a storage
+  server or other party from violating the integrity properties of the
+  read-cap: this failure was only exploitable by the uploader who
+  gives you a carefully constructed read-cap. If you download the file
+  with Tahoe 1.2.0 or later, you will not be vulnerable to this
+  problem. `#491`_
+
+  This change does not introduce a compatibility issue, because all
+  existing versions of Tahoe will emit the ciphertext hash tree in
+  their shares.
+
+Dependencies
+''''''''''''
+
+- Tahoe now requires Foolscap-0.2.9 . It also requires pycryptopp 0.5
+  or newer, since earlier versions had a bug that interacted with
+  specific compiler versions that could sometimes result in incorrect
+  encryption behavior. Both packages are included in the Tahoe source
+  tarball in misc/dependencies/ , and should be built automatically
+  when necessary.
+
+Web API
+'''''''
+
+- Web API directory pages should now contain properly-slash-terminated
+  links to other directories. They have also stopped using absolute
+  links in forms and pages (which interfered with the use of a
+  front-end load-balancing proxy).
+
+- The behavior of the "Check This File" button changed, in conjunction
+  with larger internal changes to file checking/verification. The
+  button triggers an immediate check as before, but the outcome is
+  shown on its own page, and does not get stored anywhere. As a
+  result, the web directory page no longer shows historical checker
+  results.
+
+- A new "Deep-Check" button has been added, which allows a user to
+  initiate a recursive check of the given directory and all files and
+  directories reachable from it. This can cause quite a bit of work,
+  and has no intermediate progress information or feedback about the
+  process. In addition, the results of the deep-check are extremely
+  limited. A later release will improve this behavior.
+
+- The web server's behavior with respect to non-ASCII (unicode)
+  filenames in the "GET save=true" operation has been improved. To
+  achieve maximum compatibility with variously buggy web browsers, the
+  server does not try to figure out the character set of the inbound
+  filename. It just echoes the same bytes back to the browser in the
+  Content-Disposition header. This seems to make both IE7 and Firefox
+  work correctly.
+
+Checker/Verifier/Repairer
+'''''''''''''''''''''''''
+
+- Tahoe is slowly acquiring convenient tools to check up on file
+  health, examine existing shares for errors, and repair files that
+  are not fully healthy. This release adds a mutable
+  checker/verifier/repairer, although testing is very limited, and
+  there are no web interfaces to trigger repair yet. The "Check"
+  button next to each file or directory on the wapi page will perform
+  a file check, and the "deep check" button on each directory will
+  recursively check all files and directories reachable from there
+  (which may take a very long time).
+
+  Future releases will improve access to this functionality.
+
+Operations/Packaging
+''''''''''''''''''''
+
+- A "check-grid" script has been added, along with a Makefile
+  target. This is intended (with the help of a pre-configured node
+  directory) to check upon the health of a Tahoe grid, uploading and
+  downloading a few files. This can be used as a monitoring tool for a
+  deployed grid, to be run periodically and to signal an error if it
+  ever fails. It also helps with compatibility testing, to verify that
+  the latest Tahoe code is still able to handle files created by an
+  older version.
+
+- The munin plugins from misc/munin/ are now copied into any generated
+  debian packages, and are made executable (and uncompressed) so they
+  can be symlinked directly from /etc/munin/plugins/ .
+
+- Ubuntu "Hardy" was added as a supported debian platform, with a
+  Makefile target to produce hardy .deb packages. Some notes have been
+  added to `debian.rst`_ about building Tahoe on a debian/ubuntu
+  system.
+
+- Storage servers now measure operation rates and
+  latency-per-operation, and provides results through the /statistics
+  web page as well as the stats gatherer. Munin plugins have been
+  added to match.
+
+Other
+'''''
+
+- Tahoe nodes now use Foolscap "incident logging" to record unusual
+  events to their NODEDIR/logs/incidents/ directory. These incident
+  files can be examined by Foolscap logging tools, or delivered to an
+  external log-gatherer for further analysis. Note that Tahoe now
+  requires Foolscap-0.2.9, since 0.2.8 had a bug that complained about
+  "OSError: File exists" when trying to create the incidents/
+  directory for a second time.
+
+- If no servers are available when retrieving a mutable file (like a
+  directory), the node now reports an error instead of hanging
+  forever. Earlier releases would not only hang (causing the wapi
+  directory listing to get stuck half-way through), but the internal
+  dirnode serialization would cause all subsequent attempts to
+  retrieve or modify the same directory to hang as well. `#463`_
+
+- A minor internal exception (reported in logs/twistd.log, in the
+  "stopProducing" method) was fixed, which complained about
+  "self._paused_at not defined" whenever a file download was stopped
+  from the web browser end.
+
+.. _#463: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/463
+.. _#491: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/491
+.. _debian.rst: docs/debian.rst
+
+Release 1.1.0 (2008-06-11)
+--------------------------
+
+CLI: new "alias" model
+''''''''''''''''''''''
+
+- The new CLI code uses an scp/rsync -like interface, in which
+  directories in the Tahoe storage grid are referenced by a
+  colon-suffixed alias. The new commands look like:
+
+ - tahoe cp local.txt tahoe:virtual.txt
+ - tahoe ls work:subdir
+
+- More functionality is available through the CLI: creating unlinked
+  files and directories, recursive copy in or out of the storage grid,
+  hardlinks, and retrieving the raw read- or write- caps through the
+  'ls' command. Please read `CLI.rst`_ for complete details.
+
+wapi: new pages, new commands
+'''''''''''''''''''''''''''''
+
+- Several new pages were added to the web API:
+
+ - /helper_status : to describe what a Helper is doing
+ - /statistics : reports node uptime, CPU usage, other stats
+ - /file : for easy file-download URLs, see `#221`_
+ - /cap == /uri : future compatibility
+
+- The localdir=/localfile= and t=download operations were
+  removed. These required special configuration to enable anyways, but
+  this feature was a security problem, and was mostly obviated by the
+  new "cp -r" command.
+
+- Several new options to the GET command were added:
+
+ -  t=deep-size : add up the size of all immutable files reachable from the directory
+ -  t=deep-stats : return a JSON-encoded description of number of files, size distribution, total size, etc
+
+- POST is now preferred over PUT for most operations which cause
+  side-effects.
+
+- Most wapi calls now accept overwrite=, and default to overwrite=true
+
+- "POST /uri/DIRCAP/parent/child?t=mkdir" is now the preferred API to
+  create multiple directories at once, rather than ...?t=mkdir-p .
+
+- PUT to a mutable file ("PUT /uri/MUTABLEFILECAP", "PUT
+  /uri/DIRCAP/child") will modify the file in-place.
+
+- more munin graphs in misc/munin/
+
+ - tahoe-introstats
+ - tahoe-rootdir-space
+ - tahoe_estimate_files
+ - mutable files published/retrieved
+ - tahoe_cpu_watcher
+ - tahoe_spacetime
+
+New Dependencies
+''''''''''''''''
+-  zfec 1.1.0
+-  foolscap 0.2.8
+-  pycryptopp 0.5
+-  setuptools (now required at runtime)
+
+New Mutable-File Code
+'''''''''''''''''''''
+
+- The mutable-file handling code (mostly used for directories) has
+  been completely rewritten. The new scheme has a better API (with a
+  modify() method) and is less likely to lose data when several
+  uncoordinated writers change a file at the same time.
+
+- In addition, a single Tahoe process will coordinate its own
+  writes. If you make two concurrent directory-modifying wapi calls to
+  a single tahoe node, it will internally make one of them wait for
+  the other to complete. This prevents auto-collision (`#391`_).
+
+- The new mutable-file code also detects errors during publish
+  better. Earlier releases might believe that a mutable file was
+  published when in fact it failed.
+
+other features
+''''''''''''''
+
+- The node now monitors its own CPU usage, as a percentage, measured
+  every 60 seconds. 1/5/15 minute moving averages are available on the
+  /statistics web page and via the stats-gathering interface.
+
+- Clients now accelerate reconnection to all servers after being
+  offline (`#374`_). When a client is offline for a long time, it
+  scales back reconnection attempts to approximately once per hour, so
+  it may take a while to make the first attempt, but once any attempt
+  succeeds, the other server connections will be retried immediately.
+
+- A new "offloaded KeyGenerator" facility can be configured, to move
+  RSA key generation out from, say, a wapi node, into a separate
+  process. RSA keys can take several seconds to create, and so a wapi
+  node which is being used for directory creation will be unavailable
+  for anything else during this time. The Key Generator process will
+  pre-compute a small pool of keys, to speed things up further. This
+  also takes better advantage of multi-core CPUs, or SMP hosts.
+
+- The node will only use a potentially-slow "du -s" command at startup
+  (to measure how much space has been used) if the "sizelimit"
+  parameter has been configured (to limit how much space is
+  used). Large storage servers should turn off sizelimit until a later
+  release improves the space-management code, since "du -s" on a
+  terabyte filesystem can take hours.
+
+- The Introducer now allows new announcements to replace old ones, to
+  avoid buildups of obsolete announcements.
+
+- Immutable files are limited to about 12GiB (when using the default
+  3-of-10 encoding), because larger files would be corrupted by the
+  four-byte share-size field on the storage servers (`#439`_). A later
+  release will remove this limit. Earlier releases would allow >12GiB
+  uploads, but the resulting file would be unretrievable.
+
+- The docs/ directory has been rearranged, with old docs put in
+  docs/historical/ and not-yet-implemented ones in docs/proposed/ .
+
+- The Mac OS-X FUSE plugin has a significant bug fix: earlier versions
+  would corrupt writes that used seek() instead of writing the file in
+  linear order.  The rsync tool is known to perform writes in this
+  order. This has been fixed.
+
+.. _#221: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/221
+.. _#374: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/374
+.. _#391: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/391
+.. _#439: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/439
+.. _CLI.rst: docs/CLI.rst
author	bertagaz <bertagaz@ptitcanardnoir.org>	2012-06-12 00:37:08 +0200
committer	bertagaz <bertagaz@ptitcanardnoir.org>	2012-06-12 00:37:08 +0200
commit	70b0e555ef5f880c08f09331946c83744ca310a5 (patch)
tree	e673bf4dae733ca8f2faa5a030e22f9015070dce /NEWS.rst
parent	e28117a205c07306a8ba8f502441a7b304669c41 (diff)