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

[Nate Carlson]

On Wed, 8 Jun 2005 JACOB_LIBERMAN at Dell.com wrote:
> You can add additional journals at a later time provided that you have 
> free disk space on the filesystem. At least, that was the case with GFS 
> 6.

Nifty - good to know.

> With lock_gulm, you can run with a single lock manager or redundant lock 
> managers. In a redundant lock manager config, you generally have 3-5 
> lock managers. One is elected the master lock manager and the others are 
> slaves. If the master loses conenctivity to the other nodes, the 
> majority of the remaining nodes will elect a new master.
>
> The other consideration when using lock_gulm with RLM is that lockserver 
> nodes must be fenced from network and the storage, so simply fencing on 
> a fibre switch port is not suffiencient. These means that you need 
> network power switches to fence the lock servers.

Got'cha. I should have the boxes on Masterswitches, so should be fine 
there. The only time a box would need to be fenced is when it loses 
communication, right? (So I'd still be ok running virtual machines on the 
lock servers.)

> If you have Dell PowerEdge servers, you can also fence them with the 
> Embedded Remote Access controllers. I wrote a little PERL script that 
> does so if you're interested. Theres also a similar script in the fence 
> CVS, but I like mine better. 8)

I do have PowerEdge servers, but they are 1550's, which apparently won't 
work with any of the RAC cards.  :( I was bummed to find that out.

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