Subject: ANNOUNCE: mdadm 3.3 - A tools for managing md Soft RAID under Linux I am pleased to announce the availability of mdadm version 3.3 It is available at the usual places: http://www.kernel.org/pub/linux/utils/raid/mdadm/ and via git at git://github.com/neilbrown/mdadm git://neil.brown.name/mdadm http://git.neil.brown.name/git/mdadm This is a major new release so don't be too surprised if there are a few issues. If I hear about them they will be fixed in 3.3.1. git log reports nearly 500 changes since 3.2.6 so I won't list them all. Some highlights are: - Some array reshapes can proceed without needing backup file. This is done by changing the 'data_offset' so we never need to write any data back over where it was before. If there is no "head space" or "tail space" to allow data_offset to change, the old mechanism with a backup file can still be used. - RAID10 arrays can be reshaped to change the number of devices, change the chunk size, or change the layout between 'near' and 'offset'. This will always change data_offset, and will fail if there is no room for data_offset to be moved. - "--assemble --update=metadata" can convert a 0.90 array to a 1.0 array. - bad-block-logs are supported (but not heavily tested yet) - "--assemble --update=revert-reshape" can be used to undo a reshape that has just been started but isn't really wanted. This is very new and while it passes basic tests it cannot be guaranteed. - improved locking between --incremental and --assemble - uses systemd to run "mdmon" if systemd is configured to do that. - kernel names of md devices can be non-numeric. e.g. "md_home" rather than "md0". This will probably confuse lots of other tools, so you need to echo CREATE names=yes >> /etc/mdadm.conf or the feature will not be used. (you also need a reasonably new kernel). - "--stop" can be given a kernel name instead of a device name. i.e mdadm --stop md4 will work even if /dev/md4 doesn't exist. - "--detail --export" has some information about the devices in the array - --dump and --restore can be used to backup and restore the metadata on an array. - Hot-replace is supported with mdadm /dev/mdX --replace /dev/foo and mdadm /dev/mdX --replace /dev/foo --with /dev/bar - Config file can be a directory in which case all "*.conf" files are read in lexical order. Default is to read /etc/mdadm.conf and then /etc/mdadm.conf.d Thus echo CREATE name=yes > /etc/mdadm.conf.d/names.conf will also enable the use of named md devices. - Lots of improvements to DDF support including adding support for RAID10 (thanks Martin Wilck). and lots of bugfixes and other little changes. NeilBrown 3rd September 2013