ストレージ関連

$ sudo apt-get install --no-install-recommends targetcli python-urwid
$ sudo reboot

$ sudo targetcli
/> help
(snip)
AVAILABLE COMMANDS
  The following commands are available in the current path:

    - bookmarks action [bookmark]
    - cd [path]
    - exit
    - get [group] [parameter...]
    - help [topic]
    - ls [path] [depth]
    - pwd
    - refresh
    - saveconfig
    - set [group] [parameter=value...]
    - status
    - version

/> cd backstores/pscsi
/backstores/pscsi> help
(snip)
AVAILABLE COMMANDS
(snip)
    - create name dev
    - delete name

> help create
SYNTAX
  create name dev

DESCRIPTION
  Creates a PSCSI storage object, with supplied name and SCSI device. The SCSI
  device dev can either be a path name to the device, in which case it is
  recommended to use the /dev/disk/by-id hierarchy to have consistent naming
  should your physical SCSI system be modified, or an SCSI device ID in the
  H:C:T:L format, which is not recommended as SCSI IDs may vary in time.

$ cd /usr/share/doc/python-rtslib/doc/html
$ python -m SimpleHTTPServer

initiator$ sudo blockdev --getsize64 /dev/sdb
1073741824

target$ sudo lvresize -L 2g /dev/ubuntu/i_test

initiator$ sudo iscsiadm -m session -R
Rescanning session [sid: 10, target: iqn.2012-03.com.cybozu:ymmt2:test, portal: 10.1.5.213,3260]

initiator$ sudo blockdev  --getsize64 /dev/sdb
2147483648

$ sudo apt-get install open-iscsi

$ sudo mdadm -G DEVICE --bitmap=none
$ sudo mdadm -G DEVICE --size=max
$ sudo mdadm --wait DEVICE
$ sudo mdadm -G DEVICE --bitmap=internal

+  bitmap/location
+     This indicates where the write-intent bitmap for the array is
+     stored.
+     It can be one of "none", "file" or "[+-]N".
+     "file" may later be extended to "file:/file/name"
+     "[+-]N" means that many sectors from the start of the metadata.
+       This is replicated on all devices.  For arrays with externally
+       managed metadata, the offset is from the beginning of the
+       device.
+  bitmap/chunksize
+     The size, in bytes, of the chunk which will be represented by a
+     single bit.  For RAID456, it is a portion of an individual
+     device. For RAID10, it is a portion of the array.  For RAID1, it
+     is both (they come to the same thing).
+  bitmap/time_base
+     The time, in seconds, between looking for bits in the bitmap to
+     be cleared. In the current implementation, a bit will be cleared
+     between 2 and 3 times "time_base" after all the covered blocks
+     are known to be in-sync.
+  bitmap/backlog
+     When write-mostly devices are active in a RAID1, write requests
+     to those devices proceed in the background - the filesystem (or
+     other user of the device) does not have to wait for them.
+     'backlog' sets a limit on the number of concurrent background
+     writes.  If there are more than this, new writes will by
+     synchronous.
+  bitmap/metadata
+     This can be either 'internal' or 'external'.
+     'internal' is the default and means the metadata for the bitmap
+     is stored in the first 256 bytes of the allocated space and is
+     managed by the md module.
+     'external' means that bitmap metadata is managed externally to
+     the kernel (i.e. by some userspace program)
+  bitmap/can_clear
+     This is either 'true' or 'false'.  If 'true', then bits in the
+     bitmap will be cleared when the corresponding blocks are thought
+     to be in-sync.  If 'false', bits will never be cleared.
+     This is automatically set to 'false' if a write happens on a
+     degraded array, or if the array becomes degraded during a write.
+     When metadata is managed externally, it should be set to true
+     once the array becomes non-degraded, and this fact has been
+     recorded in the metadata.