diff options
Diffstat (limited to 'mdadm.8')
| -rw-r--r-- | mdadm.8 | 36 |
1 files changed, 33 insertions, 3 deletions
@@ -225,8 +225,18 @@ slow link. .TP .BR -b ", " --bitmap= Give the name of a bitmap file to use with this array. Can be used -with --create (file should not exist) or --assemble (file should -exist). +with --create (file should not exist), --assemble (file should +exist), of --grow (file should not exist). + +The file +.B internal +can be used to indicate that the bitmap should be stored in the array, +near the superblock. There is a limited amount of space for such +bitmaps, but it is often sufficient. + +The file +.B none +can be given when used with --grow to remove a bitmap. .TP .BR --bitmap-chunk= @@ -621,6 +631,20 @@ counts of total, working, active, failed, and spare devices. hotadd listed devices. .TP +.BR --re-add +Listed devices are assumed to have recently been part of the array, +and they are re-added. This is only different from --add when a +write-intent bitmap is present. It causes only those parts of the +device that have changed since the device was removed from the array +to be reconstructed. + +This flag is only needed with arrays that are built without a +superblock (i.e. --build, not --create). For array with a superblock, +.I mdadm +checks if a superblock is present and automatically determines if a +re-add is appropriate. + +.TP .BR -r ", " --remove remove listed devices. They must not be active. i.e. they should be failed or spare devices. @@ -1268,7 +1292,7 @@ change the "raid-disks" attribute of RAID1. add a write-intent bitmap to a RAID1 array. .PP -Normally when an array is build the "size" it taken from the smallest +Normally when an array is built the "size" it taken from the smallest of the drives. If all the small drives in an arrays are, one at a time, removed and replaced with larger drives, then you could have an array of large drives with only a small amount used. In this @@ -1294,6 +1318,12 @@ devices that which were in those slots must be failed and removed. When the number of devices is increased, any hot spares that are present may be activated immediately. +A write-intent bitmap can be added to, or remove from, an active RAID1 +array. Either internal bitmap, of bitmaps stored in a separate file +can be added. Note that if you add a bitmap stored in a file which is +in a filesystem that is on the raid array being affected, the system +will deadlock. The bitmap must be on a separate filesystem. + .SH EXAMPLES .B " mdadm --query /dev/name-of-device" |