[ClusterLabs] Pacemaker in puppet with cib.xml?

[Ken Gaillot]

On 07/21/2016 02:20 PM, Stephano-Shachter, Dylan wrote:
> I am familiar with pcs cluster cib.
> 
> What I am thinking of doing is running "pcs cluster cib --config >
> config.xml" to get a valid config.
> 
> I will then put config.xml on the puppet server and have it push the
> file and run "pcs cluster cib-push --config config.xml" every hour. 
> 
> Will this cause any problems due to pushing the config multiple times?

No, that's fine.

> This would allow me to make small edits to the file in puppet and have
> it pushed automatically. If I wanted to make any big changes, I can make
> them with pcs and just pull another config.

Sounds good.

> On Thu, Jul 21, 2016 at 2:52 PM, Ken Gaillot <kgaillot at redhat.com
> <mailto:kgaillot at redhat.com>> wrote:
> 
>     On 07/21/2016 01:35 PM, Stephano-Shachter, Dylan wrote:
>     > Hello all,
>     >
>     > I want to put the pacemaker config for my two node cluster in puppet
>     > but, since it is just one cluster, it seems overkill to use the corosync
>     > module. If I just have puppet push cib.xml to each machine, will that
>     > work? To make changes, I would just use pcs to update things and then
>     > copy cib.xml back to puppet. I am not sure what happens when you change
>     > cib.xml while the cluster is running. Is it safe?
> 
>     No, pacemaker checksums the CIB and won't accept a file that isn't
>     properly signed. Also, the cluster automatically synchronizes changes
>     made to the CIB across all nodes, so there is no need to push changes
>     more than once.
> 
>     Since you're using pcs, the update process could go like this:
> 
>       # Get the current configuration:
>       pcs cluster cib --config > cib-new.xml
> 
>       # Make changes:
>       pcs -f cib-new.xml <whatever-command-you-want>
>       <etc.>
> 
>       # Upload the configuration changes to the cluster:
>       pcs cluster cib-push --config cib-new.xml
> 
>     Using "--config" is important so you only work with the configuration
>     section of the CIB, and not the dynamically determined cluster
>     properties and status.
> 
>     The first and last commands can be done on any one node, with the
>     cluster running. The "pcs -f" commands can be done anywhere/anytime.