HP XC System Software Installation Guide Version 4.0

Because HP Serviceguard is the recommended availability tool, translator scripts and other
supporting scripts are already provided for you in the HP XC Serviceguard RPM. You do not
have to write scripts if you are using Serviceguard.
Availability Tools from Other Vendors
If you are using an availability tool other than Serviceguard, you are responsible for completing
the following tasks:
1. You must write translator scripts and any other required scripts. See the vendor
documentation or contact the HP XC Support team at [e-mail] for information
about how to write these scripts.
2. When the scripts are ready, you must copy or move the scripts to the
/opt/hptc/availability/availability_tool directory for use by the
cluster_config utility.
When the cluster_config utility finds translator scripts in the
/opt/hptc/availability/availability_tool directory, you are prompted to specify
the nodes that you want to associate as members in an availability set, and you select the
availability tool you want to use to manage the availability set.
1.9.5 Determining a Strategy for Improved Availability of the /hptc_cluster File System
On a standard HP XC configuration, the clusterwide /hptc_cluster file system is locally
mounted on the head node and is exported to all other nodes in the cluster. This file system
contains configuration and log file information that is required for all nodes. When the
/hptc_cluster file system is local to the head node and the head node is unavailable, the
ability of the rest of the cluster to launch and run user jobs might be affected.
Two options are available to provide improved availability of the /hptc_cluster file system:
• HP Scalable File Share (SFS) software, which must be purchased separately from HP
• Shared fiber channel storage managed by Serviceguard for Linux, which is also purchased
separately from HP
During the HP XC Kickstart installation procedure, you are prompted to configure the
/hptc_cluster file system either on a local system disk or on another disk somewhere other
than the head node.
For either of the two availability methods (SFS or shared fiber channel storage), do not place the
/hptc_cluster on the local system disk. Instead, either create the file system on SFS, or create
a logical volume on shared storage.
1.9.6 Choosing Nodes to be Members of Availability Sets
Use the following guidelines to decide which nodes to associate into availability sets:
• If you want to configure the database server with improved availability, you must create
one availability set, containing the head node and one other node, to serve the dbserver
service. The dbserver service is served by the head node by default and cannot be moved.
• When the head node is a member of an availability set, HP recommends that the second
member in the availability set is the same hardware model type as the head node.
• The head node can be a member of only one availability set per availability tool.
• If you intend to configure nat or LVS as services for improved availability, the nodes you
associate in the availability set must have an external Ethernet connection configured as
well. You do this using the cluster_config utility.
• You cannot overlap nodes in availability sets. A node can be a member in only one availability
set per availability tool. For instance, if nodes n8 and n7 are associated into an availability
1.9 Planning a Service Availability Strategy 29