[Linux-cluster] A few GFS newbie questions: journals, etc

[Nate Carlson]

On Thu, 30 Jun 2005, Patrick Caulfield wrote:
> That is right. What you have here is cman correcting an incorrect 
> configuration. You've told it to expect only 10 votes but provided it 
> with 101 votes. It knows when you're lying to it ;-)

But darn it, I *want* to be able to lie to it! :)

> What you actually have here is a special case of a two-node cluster, 
> because there are only two "real" nodes involved. Unfortunately the cman 
> "two_node" mode is no use here because it enforces the 2-node 
> restriction which would prevent you bringing any VMs online once the two 
> real machines were up.

I've only got two physical boxes right now, but will be adding 2 more in 
the near future (once I migrate all the services off the boxes in my old 
colo to the new one.)

> One little-known feature is that you can set votes to zero (only in CCS, 
> not from the cman_tool command-line) which may go a little way to 
> helping out. it would, at least, work for 3 or more Xen host nodes if 
> all the VMs had zero votes.

I'm not sure how that would help - if I lose another physical host, won't 
it still lose quorum? But sounds like a good idea anyways - I'll drop the 
VM's down to 0 votes.

> Perhaps we should change "2-node" mode to allow >2 nodes provided the 
> extra nodes all had zero votes ?

If possible, an option that would let me say "here's the number required 
for a quorum, I know I'm lying to you, but do it anyways" would be nice. 
:)

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| nate carlson | natecars at natecarlson.com | http://www.natecarlson.com |
|       depriving some poor village of its idiot since 1981            |
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