[KLUG Members] Server Mirroring

[Jeremy Leonard]

Jamie McCarthy wrote:

>lists at elite4god.com (Jeremy Leonard) wrote, back in October:
>
>  
>
>>The software I want to mirror is Novell GroupWise.
>>I think I've found a solution. DRBD.
>>This will create a virtual block device that will mirror the data
>>between two servers.
>>This is below the file level.
>>This coupled with HeartBeat should do the trick.
>>    
>>
>
>Jeremy,
>
>Did you end up implementing DRBD?  Did it work for you?
>  
>
I did. It worked.

It's best as one live server and the other as a standby. Trying to have 
them both running in sort of a load balancing situation doesn't work well.

Everything failed over with a single failure. There was no data corruption.

If you failed both servers at the same time, however, you had to wait 
for the virtual device to rebuild. In this case it would do a full sync 
and on 400gb it took about 32 hours.

Master/slave was stable though. If the master failed the slave would 
take over no problem. When the master came back online it would rebuild 
in the background.

If you have any other questions let me know.

My client wanted load balancing so they purchased an actual SAN. An HP 
MSA500. This is working very well.