[Pacemaker] Getting Started

[stjoanis]

Brett Maton <brett.maton at ...> writes:

> 
> Hi Takatoshi,
> 
>    I probably did start the slave node manually.
>   I think I'm getting stuck with not knowing how to properly manage start-up
> and shutdowns with the cluster.
>   I can get it all up and running (somehow ;)), but I don't understand how
> to restore the master and slave to their original states.
> 
>   Taking a new base backup / rsync'ing the WAL logs is no problem, just
> how-to manage the service with crm is tripping me up and I  haven't figured
> out how to read the logs (/var/log/corosync.log) yet....
> 
> Again, thank you all for your patience.
> Brett

In fact, the sample configuration given by Takatoshi takes use of ping service 
to state if a node replies (as I can understand it..)
I choose another way to make its great agent drive well my two nodes with Slave 
and Master combination :
First I've set up a DRBD resource, because for other reason I need a share 
storage.
Then I have a group of Services that follows the DRBD Master (which is a MS 
clone in fact)
Finally my PGSQL resource is a MS (MultiState) too, that follows the DRBD as 
well (thanks to colocation rules).
So the PG Master MUST always be same as DRBD Master, and this is moreover fine 
because my Services contains a VIP with which I can connect to the Master PG (in 
read/write).
Additionnally, I can use the PG Slave as a read/only database.
Got the scheme ?