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

[Nate Carlson <rhcluster natecarlson com>]

Hey all,

Few hopefully easy questions for all you GFS geniouses. :)

I've created a test GFS cluster per the docs at:

http://sourceware.org/cluster/doc/usage.txt

First of all, when creating the filesystem, the docs state:

"gfs_mkfs -p lock_dlm -t <ClusterName>:<FSName> -j <Journals> <Device>
<Journals> the number of journals in the fs, one for each node to mount"

So this should be one journal for any node I may want to mount in the 
future? Is there any problem with having this set to a high number? (I've 
currently got 4 nodes, but will be running Xen domains on top of each of 
those nodes which will also be running GFS, so I could have 15-20 nodes 
easily).

Second, I see that the docs are using lock_dlm for everything; is this the 
recommended approach now? What are the major differences between lock_dlm 
and lock_gulm?

Third, just a question about how voting and such works. Again, with the 
possibility of 15-20 nodes, I'd still like to be able to use the GFS 
filesystem even if only one node is currently up. Is there anything I need 
to tweak to be able to do that?

Thanks much!

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