[ZODB-Dev] Clustering ZEO Server with drbd

[Christian Theune]

garthpl at periweb.com wrote:
> If you setup drbd and heartbeat , the spare will take over the floating 
> ip from the zeo server and restart the service. drbd is simply doing a 
> block level replication of the zeo server file system where the zeo data 
> is stored. The question is what files needs to be replicated so that 
> when the the service is restarted on the spare, all the files needed by 
> the zeo server to operate are there? I'm trying to ensure from a system 
> architecture standpoint I'm not missing anything.

When using FileStorage, you'd need the Data.fs.* files, except Data.fs.lock.

In the end, this might not be exactly HA because you'll have a period of 
time that isn't covered and may stretch for quite a while. (But I don't 
know about the HA terminology anyway...)

(Re)starting the ZEO server when it is needed might take a while on 
large databases if the index file happens to be broken.

Christian

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