[Gluster-devel] HA failover question.

[Chris Johnson]

On Wed, 17 Oct 2007, Kevan Benson wrote:

      Hm.  Ok, different question.

      If I have two file severs/nodes.  I can put the AFR stuff in the
client end (stills seems odd as desktops get rebooted all the time).
Can multiple clients set up for AFR across both these servers access
them and the files at the same time?  Can the access the same file at
the same time.  Reads obviouly, writes would have the same issues as
EXT3 or ReiserFS or whatever with that.  GlusterFS team?  Really
curious how self healing works with the client end doing the AFR.

      Another question.  Could two servers each doing local unify be
AR'ed from the client side?

Tnx.

> Chris Johnson wrote:
>> On Wed, 17 Oct 2007, Kevan Benson wrote:
>> 
>>      If I'm reading this right then, I CAN have two servers with two
>> SHARED file systems and multiple AFR'ed client setups accessing them?
>> This would seem to require serious locking and sever to sever
>> communications to pull off.
>
> You can specify the lock server for an AFR, but it defaults to the first 
> specified subvolume I believe.  Each client requests a lock from that server. 
> I can see some situations where there might be lock guarantee problems 
> (server invisible to some but not all clients), but it I don't know the 
> details of how it works.
>
> -- 
>
> -Kevan Benson
> -A-1 Networks
>
>
>

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