6.9. Manually Moving Resources Around the Cluster
There are always times when an administrator needs to override the cluster and force resources to move to a specific location. Underneath we use location constraints like the one we created above, happily you don’t need to care. Just provide the name of the resource and the intended location, we’ll do the rest.
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Last updated: Fri Aug 28 16:19:24 2009
Stack: openais
Current DC: pcmk-2 - partition with quorum
Version: 1.1.5-bdd89e69ba545404d02445be1f3d72e6a203ba2f
2 Nodes configured, 2 expected votes
2 Resources configured.
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Online: [ pcmk-1 pcmk-2 ]
ClusterIP (ocf::heartbeat:IPaddr): Started pcmk-1
WebSite (ocf::heartbeat:apache): Started pcmk-1
Notice how the colocation rule we created has ensured that ClusterIP was also moved to pcmk-1. For the curious, we can see the effect of this command by examining the configuration
node pcmk-1
node pcmk-2
primitive WebSite ocf:heartbeat:apache \
params configfile="/etc/httpd/conf/httpd.conf" \
op monitor interval="1min"
primitive ClusterIP ocf:heartbeat:IPaddr2 \
params ip="192.168.122.101" cidr_netmask="32" \
op monitor interval="30s"
location cli-prefer-WebSite WebSite \
rule $id="cli-prefer-rule-WebSite" inf:
location prefer-pcmk-1 WebSite 50: pcmk-1
colocation website-with-ip inf: WebSite ClusterIP
property $id="cib-bootstrap-options" \
dc-version="1.1.5-bdd89e69ba545404d02445be1f3d72e6a203ba2f" \
cluster-infrastructure="openais" \
expected-quorum-votes="2" \
stonith-enabled="false" \
no-quorum-policy="ignore"
rsc_defaults $id="rsc-options" \
resource-stickiness="100"
Highlighted is the automated constraint used to move the resources to pcmk-1
6.9.1. Giving Control Back to the Cluster
Once we’ve finished whatever activity that required us to move the resources to pcmk-1, in our case nothing, we can then allow the cluster to resume normal operation with the unmove command. Since we previously configured a default stickiness, the resources will remain on pcmk-1.
node pcmk-1
node pcmk-2
primitive WebSite ocf:heartbeat:apache \
params configfile="/etc/httpd/conf/httpd.conf" \
op monitor interval="1min"
primitive ClusterIP ocf:heartbeat:IPaddr2 \
params ip="192.168.122.101" cidr_netmask="32" \
op monitor interval="30s"
location prefer-pcmk-1 WebSite 50: pcmk-1
colocation website-with-ip inf: WebSite ClusterIP
property $id="cib-bootstrap-options" \
dc-version="1.1.5-bdd89e69ba545404d02445be1f3d72e6a203ba2f" \
cluster-infrastructure="openais" \
expected-quorum-votes="2" \
stonith-enabled="false" \
no-quorum-policy="ignore"
rsc_defaults $id="rsc-options" \
resource-stickiness="100"
Note that the automated constraint is now gone. If we check the cluster status, we can also see that as expected the resources are still active on pcmk-1.
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Last updated: Fri Aug 28 16:20:53 2009
Stack: openais
Current DC: pcmk-2 - partition with quorum
Version: 1.1.5-bdd89e69ba545404d02445be1f3d72e6a203ba2f
2 Nodes configured, 2 expected votes
2 Resources configured.
============
Online: [ pcmk-1 pcmk-2 ]
ClusterIP (ocf::heartbeat:IPaddr): Started pcmk-1
WebSite (ocf::heartbeat:apache): Started pcmk-1