[Linux-cluster] Using GULM with CLVM

[Patrick Caulfield]

Ugo PARSI wrote:
> Hello,
> 
> I am having way too much problems with CMAN/DLM on a midsize cluster
> (random kernel panics, freezes, random quorum dropping issues, cluster
> split view, etc..) and just saw that it was more preferable to use
> GULM for mid to large sized clusters and that CMAN wasn't tested on
> more than 32 nodes.
> 
> Actually, I am using the RedHat Cluster Suite only for CLVM, and some
> people are saying that CLVM+GULM is supported but as I can see on the
> official 'documentation'  :
> 
> http://sourceware.org/cluster/gulm/gulmusage.txt :
> 
> 'This document does not cover setting up a block device to run on.
> Mostly because CLVM doesn't work with gulm yet'
> 
> What's the current position on that please ?
> Is the documentation outdated ?


Yes, it is outdated. clvmd does work with gulm.

> Also, my whole infrastructure is totally virtualized (with Xen), and
> it is also said that it's better to use GULM on a dedicated computer.
> Anyone tried that on a dedicated virtual machine ?
> 128 or 256 Megs of RAM should be enough or GULM is ressource hungry ?
> 

gulm is resource hungry. Get as much RAM as you can ;-)
I'm no expert on gulm, but I would expect that 256MB would not be enough for a
cluster of over 32 nodes.

-- 

patrick