HP XC System Software Installation Guide Version 4.0

IMPORTANT: Any service that is only present on the head node cannot be moved. Those services
are delivered in the avail_node_management role.
Thus, to achieve improved availability of those services, you must:
• Configure the head node into an availability set with one additional node.
• Assign the avail_node_management role to the other node.
Table 1-2 Role and Service Placement for Improved Availability
Special Considerations for Role Assignment
Service is Delivered in This
RoleService Name
The hptc_cluster_fs service is present on the head node
by default and cannot be moved. Thus, to achieve improved
availability of the hptc_cluster_fs service, you must assign
the avail_node_management role to the other node in the
availability set with the head node.
Using Serviceguard to enable improved availability of the
/hptc_cluster file system requires shared fiber channel
storage connecting the head node and the other node in the
availability set. The shared storage must contain an LVM
volume that includes an ext3 file system type for
/hptc_cluster to be mounted locally on one of the nodes
and served to the rest of the nodes in the HP XC configuration.
For more information about creating an LVM volume, see
Section 3.6.3 (page 61).
This configuration enables Serviceguard to relocate the
/hptc_cluster file system to the second node in the
availability set if the HP XC head node becomes unavailable.
Dependency on Other Services: None.
avail_node_managementhptc_cluster file
system
(hptc_cluster_fs)
The dbserver service is present on the head node by default
and cannot be moved.
Thus, to achieve improved availability of the dbserver
service, you must:
• Configure the head node into an availability set with one
additional node.
• Assign the avail_node_management role to the
additional node.
When improved availability is enabled, the database tables
are moved to the clusterwide /hptc_cluster file system
(rather than the default location in the /var/lib/mysql
directory).
Dependency on Other Services: To be highly available, the
dbserver service requires that you install and configure the
HP Scalable File Share (SFS) software or requires you to
configure an LVM volume for the /hptc_cluster file system
on shared fibre channel storage managed by Serviceguard.
For more information about creating an LVM volume, see
Section 3.6.3 (page 61).
For more information about the avail_node_management
role, see Section F.3.2 (page 217).
avail_node_management
Database server
(dbserver)
1.9 Planning a Service Availability Strategy 31