Re: [linux-lvm] LVM high availability

[Zdenek Kabelac <zkabelac@redhat.com>]

Dne 23.6.2013 16:32, lihuiba napsal(a):
>
>>>> 3) how about thin pool and volumes?
>>>
>>
>>Thin-pool may be active on single-node only. In cluster only exclusive
>>activation is allowed and can not be activated elsewhere even "read-only".
>>
>>It should work fine without cluster locking while read-only everywhere,
>>except you can not enforce read-only on the pool. (There is a bug for that.)
>>
>>Attempting to write to pool active elsewhere, may render the pool's view
>>corrupted on other nodes. So when writing to pool, you should at least
>>deactivate the pool and all thin volumes on all other nodes, and
>>reactivate afterwards.
>
> I don't think out why thin volumes can not be active on multiple nodes even read-only.
>
> It is intuitive that activating thin volumes in read-only mode will neither change it's own
>
> meta-data nor the pool's.
>
> If I "force" the thin volumes to be active by, for example, changing the source code,
>
> what errors will occur?


lvm2 code currently doesn't support activation of all thin pool related LVs in 
read-only mode - there is some work being done in this area - but still not 
finished.

Zdenek