Recovering From Offline Compressed Volumes - IBM Storwize V7000 Unified Problem Determination Manual

Results
If the fix procedures do not bring back a file system volume online, contact your
service provider for assistance.

Recovering from offline compressed volumes

Recovering from offline compressed volumes. Getting them back online.
When a Storwize V7000 storage pool (MDisk Group) runs out of space:
v Any volume that tries to expand (such as new data being written to a
compressed volume) is taken offline.
v Taking a file volume offline takes the Network Shared Disk (NSD) offline
because each NSD is made from one file volume.
v Taking meta data (NSD) offline takes the whole file system offline (but putting
meta data in a compressed volume is not allowed).
v The file system is unmounted if it is offline for more than 30 seconds.
v This is different from the file system filling up, which causes the file system to
enter read only mode.
There are two options to recover from this:
v Decrease the file system size.
v Increase the storage pool capacity.
Table 42.
Scenario
Storage pool warning (80%
full)
Compression ratio wrong
(file system still online)
Storage pool full
system offline)
Storage pool full
system offline)
available storage
Increasing the Storage pool capacity
To increase storage pool capacity, add more RAID arrays to the storage pool using
the management GUI.
Storage can be taken or borrowed from the block allocation to resolve out of space
conditions in the file allocation. Point in time block copies are a good candidate for
deletion.
Storwize V7000 Unified can virtualize external block storage controllers. If spare
capacity is available on other block storage controllers then you can virtualize
those and use that free local arrays.
Recovery Procedure
Provision more storage to
pool
Increase the storage to pool
size
Or
Decrease the file system size
(file Provision more storage to
pool
(file Borrow hot spare disks,
No bring file system online, free
up space, shrink filesystem,
return hot spare disks
Who does it?
You
You (Storwize V7000 fix
procedure)
You (with help from this
page)
You (with help from IBM
Remote Technical support)
You (Storwize V7000 fix
procedure)
You (with help fro IBM
Remote Technical Support)
Chapter 7. Recovery procedures
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