This can be written only while the array is being assembled, not
after it is started.
- layout
- The "layout" for the array for the particular level. This is
- simply a number that is interpretted differently by different
- levels. It can be written while assembling an array.
-
- resync_start
- The point at which resync should start. If no resync is needed,
- this will be a very large number. At array creation it will
- default to 0, though starting the array as 'clean' will
- set it much larger.
-
new_dev
This file can be written but not read. The value written should
be a block device number as major:minor. e.g. 8:0
available. It will then appear at md/dev-XXX (depending on the
name of the device) and further configuration is then possible.
- safe_mode_delay
- When an md array has seen no write requests for a certain period
- of time, it will be marked as 'clean'. When another write
- request arrive, the array is marked as 'dirty' before the write
- commenses. This is known as 'safe_mode'.
- The 'certain period' is controlled by this file which stores the
- period as a number of seconds. The default is 200msec (0.200).
- Writing a value of 0 disables safemode.
-
- array_state
- This file contains a single word which describes the current
- state of the array. In many cases, the state can be set by
- writing the word for the desired state, however some states
- cannot be explicitly set, and some transitions are not allowed.
-
- clear
- No devices, no size, no level
- Writing is equivalent to STOP_ARRAY ioctl
- inactive
- May have some settings, but array is not active
- all IO results in error
- When written, doesn't tear down array, but just stops it
- suspended (not supported yet)
- All IO requests will block. The array can be reconfigured.
- Writing this, if accepted, will block until array is quiessent
- readonly
- no resync can happen. no superblocks get written.
- write requests fail
- read-auto
- like readonly, but behaves like 'clean' on a write request.
-
- clean - no pending writes, but otherwise active.
- When written to inactive array, starts without resync
- If a write request arrives then
- if metadata is known, mark 'dirty' and switch to 'active'.
- if not known, block and switch to write-pending
- If written to an active array that has pending writes, then fails.
- active
- fully active: IO and resync can be happening.
- When written to inactive array, starts with resync
-
- write-pending
- clean, but writes are blocked waiting for 'active' to be written.
-
- active-idle
- like active, but no writes have been seen for a while (safe_mode_delay).
-
-
sync_speed_min
sync_speed_max
This are similar to /proc/sys/dev/raid/speed_limit_{min,max}
faulty - device has been kicked from active use due to
a detected fault
in_sync - device is a fully in-sync member of the array
- writemostly - device will only be subject to read
- requests if there are no other options.
- This applies only to raid1 arrays.
spare - device is working, but not a full member.
This includes spares that are in the process
of being recoverred to
This list make grow in future.
- This can be written to.
- Writing "faulty" simulates a failure on the device.
- Writing "remove" removes the device from the array.
- Writing "writemostly" sets the writemostly flag.
- Writing "-writemostly" clears the writemostly flag.
errors
An approximate count of read errors that have been detected on
git://git.onelab.eu / linux-2.6.git / blobdiff