[Linux-cluster] RHEL 4: quorate or inquorate

[Patrick Caulfield]

Dex Chen wrote:
> Thanks for the response.
> 
> I figured out the cause. I used "cman_tool leave remove" when I shutdown
> the other 2 nodes. In this way, the remaining one/cluster had "quorum:
> 1, and expected vote 1". I was surprised that the "2 node cluster"
> special case did not prevent this.

'cman_tool leave remove' is one of those "I know what I'm doing" commands.

> My remaining question is:
> Do you see any potential risks such as "split brain" when the stopped
> nodes come back, especially in a more-node cluster (say 5 node cluster)?

As soon as you add a node back in, it will impose its version of expected votes
on the cluster and it will go inquorate again. once you have (in your example) 3
nodes in the cluster all will start working normally.

-- 
Patrick

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