Setting basic cluster properties
Once your Pacemaker cluster is set up, it is recommended to set a few
basic cluster properties. To do so, start the crm shell and change
into the configuration menu by entering
configure. Alternatively. you may jump straight into the Pacemaker
configuration menu by typing crm configure directly from a shell
prompt.
Then, set the following properties:
property no-quorum-policy="ignore" \ # 
pe-warn-series-max="1000" \ # 
pe-input-series-max="1000" \
pe-error-series-max="1000" \
cluster-recheck-interval="5min" # 
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Setting no-quorum-policy="ignore" is required in 2-node Pacemaker
clusters for the following reason: if quorum enforcement is enabled,
and one of the two nodes fails, then the remaining node can not
establish a majority of quorum votes necessary to run services, and
thus it is unable to take over any resources. The appropriate
workaround is to ignore loss of quorum in the cluster. This is safe
and necessary only in 2-node clusters. Do not set this property in
Pacemaker clusters with more than two nodes.
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Setting pe-warn-series-max, pe-input-series-max and
pe-error-series-max to 1000 instructs Pacemaker to keep a longer
history of the inputs processed, and errors and warnings generated, by
its Policy Engine. This history is typically useful in case cluster
troubleshooting becomes necessary.
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Pacemaker uses an event-driven approach to cluster state
processing. However, certain Pacemaker actions occur at a configurable
interval, cluster-recheck-interval, which defaults to 15 minutes. It
is usually prudent to reduce this to a shorter interval, such as 5 or
3 minutes.
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Once you have made these changes, you may commit the updated
configuration.
