HP XC System Software Installation Guide Version 3.2

The login role supplies a node with the LVS director service, which handles the placement of
user login sessions on login nodes when a user logs in to the cluster alias.
To achieve improved availability of the LVS director service, you must assign the login role to
three nodes. See the role assignment guidelines listed in Table 1-2 (page 32) for more information.
The configuration and management database name for the service supplied by this role is lvs.
F.3.9 Management Hub Role
A node with the management_hub role is an aggregation point for management activities.
The configuration and management database names of the services provided by this role are as
follows:
• Nagios monitor (nagios_monitor)
• SuperMon aggregator (supermond)
• Syslogng (syslogng_forward)
These services are used to support scaling of the cluster. Nodes with this role provide local
storage for aggregation of system logs and performance information. Management hub services
typically report up to the node with the management_server role.
You can assign the management_hub role to several nodes, and HP recommends that you
consider using one management hub for every 64 to 128 nodes.
If you add the management_hub role to nodes in the system, HP recommends that you also
add the console_network role as well. If the console_network role is not on a
management_hub node, the hub picks a node that is assigned with the console_network
role. See “Console_network Role” (page 212) for more information.
F.3.10 Management Server Role
The management_server role contains services that manage the overall management
infrastructure. Only one node in the system can have the management_server role; in this
release, the head node has this role.
To achieve improved availability of the Nagios master service, you must assign the
management_server role to two nodes (the head node and one additional node). See the role
assignment guidelines listed in Table 1-2 (page 32) for more information.
The configuration and management database names of the services provided by this role are as
follows:
• Apache web server (httpd)
• Nagios aggregator (nagios)
• Nagios service (nsca)
F.3.11 NIS Server Role
The nis_server role is not enabled by default. Assigning this role to a node configures the
node as a NIS slave server. If you assign this role to a node, you are prompted to enter the name
of the NIS master server and NIS domain name during cluster_config processing.
Any node assigned with the nis_server role must also have an external Ethernet network
connection defined.
nis is the configuration and management database of the service provided by this role.
F.3.12 Node Management Role
Nodes with the node_management role run a number of services that help manage other nodes
in the system. This role is restricted to the head node; it cannot be removed.
The configuration and management database names of the services provided by this role are as
follows:
• Console management facility master (cmf)
• Database server (dbserver)
F.3 Role Definitions 213