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

[Nate Carlson]

On Wed, 8 Jun 2005, Lon Hohberger wrote:
> Need one journal per node, physical or virtual.  So, 20 is your magic 
> number.

Got'cha. Is there any way to expand this at a later date, or I want to set 
it to the highest possible number right away?

> lock_dlm is symmetric, lock_gulm is client/server.  Generally, your lock 
> servers should not be accessing the GFS file system, though it is 
> allowed.  This gives a lower chance of failures for the lock servers.

<...>

> (b) an asymmetric setup with a separate lock server cluster.  GFS 
> Clients connecting to the lock server cluster have no "votes" at all, so 
> as long as a majority of the lock server cluster is online, any one of 
> the GFS cluster nodes can come online and access the file system.

I think this sounds like a reasonable way to go - make the physical 
servers (or a couple of them) the lock servers, and set up the GFS clients 
as client-only. For this case, will I need to do lock_gulm? If so, I'll 
have to do some research on how to set that up.

> With most lock_dlm setups, nodes have one vote.  In that case, you must 
> have...
>
>  floor((n+1)/2)
>
> ...nodes online for a quorum to form (except in the 2-node case).

Great - thanks!

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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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