[Pacemaker] 2 web and 2 db servers both with drbd. Questions concerning the set-up

[Oliver Hoffmann]

Am Tue, 4 May 2010 15:02:54 +0200
> Hi list,
> 
> I almost have a set-up which looks like this:
> 
> 
>   Master side		  Slave side
> 
>   ---------virtual IP----------
>   |                           |
> web1----drbd/pacemaker------web2
>   |                           |
>   internal                 internal
>   |                           |
>   |                           |
> db1----drbd/pacemaker-------db2
> 
> 
> The web (apache + tomcat) and db (mysql + postgresql) servers have
> their data on a drbd device each. The internal connection is for
> better performance of the db queries and redundancy. 
> 
> How do I ensure that web2 AND db2 take the resources if web1 and/or
> db1 fail?
> 
> Thanks for input!
> 
> Regards,
> 
> Oliver
> 
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I have an idea. I don't want automatic fallback btw. So, why not a
simple monit, which does a crm standby in case of a failure of the other
master/slave pair?