HP XC System Software Administration Guide Version 4.0

scripts could choose that each use a disjoint 5 of 10 servers passed in order to spread the load.
At present, for services that are part of the same role, there are no mechanisms in place to achieve
this.
4.6.7 Advance Planning
You use the cluster_config utility to assigns roles, and hence, services, to nodes. To add a
new service to the roles model, perform one of the following:
• Add a new service to an existing role or roles.
• Add a new role or roles for the new service, and add the new service into the new role or
roles.
Ask yourself the following questions when you are adding a customized service to your HP XC
system:
• Is this a service or a policy?
• Does the service have specific servers?
• Does the service have specific clients?
• Does the service have specific daemons?
• Where do configuration steps need to occur?
If you have a systemwide policy or behavior, an sconfigure script may be all you need. Any
changes made in sconfigure scripts become part of the golden image.
Typically, if the service needs to run on specific servers and clients, you perform these tasks:
1. Edit the roles_services.ini file to include the new service or service name and roles
or both as appropriate. See “Editing the roles_services.ini File” for more information about
editing this file.
2. Create a service_name.ini file to provide service configuration details to the
cluster_config utility. See “Creating a service.ini File” (page 71) for more information
about the contents of this file.
3. Write a gconfigure script for any service configuration that is part of the golden image.
4. Write a nconfigure script for any service configuration that varies by server.
5. Write a cconfigure script for any service configuration that varies by client.
In general, your customized service configuration might require gconfigure, nconfigure,
and cconfigure scripts for any new service, but you only have to provide the scripts actually
needed to perform the configuration. For example, many services need no special client
configuration and do not require a cconfigure script.
4.6.8 Editing the roles_services.ini File
Adding a new service to the roles model requires you to do one of the following:
• Add the service to an existing role or roles
• Add a new role or roles for the new service and add the new service into the new role or
roles
You can accomplish both these tasks by editing the /opt/hptc/config/roles_services.ini
file and adding the new service name to an existing role or a new role. This file is organized into
stanzas as follows:
• The first stanza lists all the roles:
[global]
roles = <<EOT
node_management
avail_node_management
compute
.
.
70 Managing and Customizing System Services