[Linux-cluster] architecture discussion -- NFS clustering with iSCSI

[gordan at bobich.net]

>>> In an active-standby NFS cluster scenario, is GFS still required as
>>> the format for the data drives?  I would be using a 2 node cluster so
>>> I would need a quorum disk too.  Since only 1 node will have access at
>>> any one time, could I get away with ext3 (or whatever) formatted
>>> volumes?
>>
>> As long as you can absolutely guarantee that no more than 1 node will
>> mount the volume, yes, you can use ext3.
>>
>>> Along the same note, I am going to ask an obvious question and answer
>>> it myself.  :)   In an active-active, this would definitely need to be
>>> GFS formatted, correct?
>>
>> Yes.
>>
>>
>> Gordan
>>
>
> Only in very strange situations (bug) would 2 nodes want to read/write
> to the same file.  That being said, the cluster service would also
> prevent this too, correct?

No. GFS requires clustering to be up and running. ext3 doesn't. Cluster 
would in no way stop you from mounting the same iSCSI volume on both nodes 
and mounting the same ext3 fs from both of them. You'll just notice that 
the data gets completely trashed in very short order.

Gordan