HP P6000 Cluster Extension Software Administrator Guide (5697-0986, June 2011)

NOTE:
IPMI fencing can be used for Integrity servers that do not support RIBCL scripting.
Networking in an SLE HA cluster
Configuring redundant and independent cluster communication paths is a good way to avoid Split
Brain conditions. With redundancy in communication paths, the loss of a single interface or switch
does not break the communication between nodes and prevents Split Brain conditions.
Administrators can configure multiple independent communication paths. HP recommends using
bonded Ethernet channels.
Resource constraints
Resource constraints allow administrators to specify which cluster nodes resources can run on, the
order resources are loaded, and the other resources a specific resource is dependent on.
There are three types of resource constraints:
• Resource location: Defines the nodes on which a resource can run, cannot run, or is preferred to
be run.
• Resource colocation: Defines which resources can or cannot run together on a node.
• Resource order: Defines the sequence of actions for resources running on a node.
Resource operation attribute
SLE HA does not monitor resource health by default. To enable this feature, add the monitor operation
to the resource definition. You can specify the interval attribute and the timeout attribute for a monitor
operation. The interval attribute defines the time interval in which the monitor operation is executed.
The timeout attribute determines how long to wait before considering the resource as failed.
Define start, stop, and monitor operations for the P6000 Cluster Extension resource.
P6000 Cluster Extension resource dependency
A Group resource in an SLE HA cluster ensures that the member resource agents are started and
stopped in the required order. A P6000 Cluster Extension resource must be added as the first member
of the group. This way, all primitive resources added after the P6000 Cluster Extension resource are
dependent on P6000 Cluster Extension.
Since the primitive resources within a resource group can be failed over independently, set a collocation
constraint for each resource group ID with the last resource in the group to achieve the failover of the
entire group when any primitive resource fails.
Failover order
Use location constraints to define the failover order for a resource group.
For each node, define a location constraint with the appropriate score to prioritize the resource group
on that particular node. During failover, the cluster calculates the score of the resource group on the
available nodes, and the node with the highest score is considered the next preferred owner. For
more information, see the SLE HA documentation.
HP P6000 Cluster Extension Software Administrator Guide 13