This use case requires that you create four cluster resources. To ensure these resources all run on the same node, they are configured as part of the resource group
apachegroup. The resources to create are as follows, listed in the order in which they will start.
IPaddr2 resource, which is a floating IP address for the
apachegroup resource group. The IP address must not be one already associated with a physical node. If the
IPaddr2 resource's NIC device is not specified, the floating IP must reside on the same network as the statically assigned IP addresses used by the cluster nodes, otherwise the NIC device to assign the floating IP address cannot be properly detected.
The following procedure creates the resource group
apachegroup and the resources that the group contains. The resources will start in the order in which you add them to the group, and they will stop in the reverse order in which they are added to the group. Run this procedure from one node of the cluster only.
The following command creates the LVM resource
my_lvm. This command specifies the
exclusive=true parameter to ensure that only the cluster is capable of activating the LVM logical volume. Because the resource group
apachegroup does not yet exist, this command creates the resource group.
pcs resource create my_lvm LVM volgrpname=my_vg \
exclusive=true --group apachegroup
When you create a resource, the resource is started automatically. You can use the following command to confirm that the resource was created and has started.
pcs resource show
Resource Group: apachegroup
my_lvm (ocf::heartbeat:LVM): Started
You can manually stop and start an individual resource with the
pcs resource disable and
pcs resource enable commands.
The following commands create the remaining resources for the configuration, adding them to the existing resource group
pcs resource create my_fs Filesystem \
device="/dev/my_vg/my_lv" directory="/var/www" fstype="ext4" --group \
pcs resource create VirtualIP IPaddr2 ip=198.51.100.3 \
cidr_netmask=24 --group apachegroup
pcs resource create Website apache \
statusurl="http://127.0.0.1/server-status" --group apachegroup
After creating the resources and the resource group that contains them, you can check the status of the cluster. Note that all four resources are running on the same node.
Cluster name: my_cluster
Last updated: Wed Jul 31 16:38:51 2013
Last change: Wed Jul 31 16:42:14 2013 via crm_attribute on z1.example.com
Current DC: z2.example.com (2) - partition with quorum
2 Nodes configured
6 Resources configured
Online: [ z1.example.com z2.example.com ]
Full list of resources:
myapc (stonith:fence_apc_snmp): Started z1.example.com
Resource Group: apachegroup
my_lvm (ocf::heartbeat:LVM): Started z1.example.com
my_fs (ocf::heartbeat:Filesystem): Started z1.example.com
VirtualIP (ocf::heartbeat:IPaddr2): Started z1.example.com
Website (ocf::heartbeat:apache): Started z1.example.com
Once the cluster is up and running, you can point a browser to the IP address you defined as the
IPaddr2 resource to view the sample display, consisting of the simple word "Hello".
If you find that the resources you configured are not running, you can run the
pcs resource debug-start resource command to test the resource configuration. For information on the
pcs resource debug-start command, see the High Availability Add-On Reference manual.