[Linux-cluster] GFS on SAN, does a quorum make sense?

[Dan B. Phung]

actually, it doesn't even work with what I thought I could do, which is to
have each node have a vote count equal to the quorum, since the vote count
is summed and halved.  ...you guys are tricky ;)

so help is needed, or maybe a pointer to a thread on where this has
been discussed previously.  

thanks,
dan


On 5, May, 2005, Dan B. Phung declared:

> Hello, I was wondering if a quorum makes sense when I have one underlying
> shared device.  My setup is this:
> 
> 
>            blade1 b2  b3  b4  b5  .....
>               \    |   |   |   |  |  |  /
>                [ fiber switch module ] 
>                         |  | 
>                   [FastT500/EXP500] 
> 
> and I want any blade to be able to access the storage at anytime.  right
> now I have my configuration such that each node has the number of votes
> equivalent to the quorum.  Does this make sense?  From my understanding,
> the quorum/voting procedure is to prevent split-brain scenarios where two
> nodes coming up for the first time might try to form two separate clusters
> of the same name, which will cause data corruption.  How would I prevent
> that, while still allowing any one node, even by itself, to access the
> storage media.
> 
> Another use of the quorum is for distributed disks in the case of a node
> failure the I/O to that disk is fenced.  Is that correct?
> 
> regards,
> Dan
> 
> 

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