Sun Cluster 3.1 Data Service Planning and Administration Guide

How to Create a Scalable Resource Group

A scalable resource group is used with scalable services. The shared address feature is the Sun Cluster networking facility that enables the multiple instances of a scalable service to appear as a single service. You must first create a failover resource group that contains the shared addresses on which the scalable resources depend. Next, create a scalable resource group, and add scalable resources to that group.

See the scrgadm(1M) man page for additional information.


Note –

Perform this procedure from any cluster node.


  1. Become superuser on a cluster member.

  2. Create the failover resource group that holds the shared addresses that the scalable resource will use.

  3. Create the scalable resource group.


    # scrgadm -a -g resource-group \
    -y Maximum_primaries=m \
    -y Desired_primaries=n \
    -y RG_dependencies=depend-resource-group \
    -h nodelist]
    -a

    Adds a scalable resource group.

    -g resource-group

    Specifies your choice of the name of the scalable resource group to add.

    -y Maximum_primaries=m

    Specifies the maximum number of active primaries for this resource group.

    -y Desired_primaries=n

    Specifies the number of active primaries on which the resource group should attempt to start.

    -y RG_dependencies=depend-resource-group

    Identifies the resource group that contains the shared address resource on which the resource group that is being created depends.

    -h nodelist

    Specifies an optional list of nodes on which this resource group is to be available. If you do not specify this list, the value defaults to all of the nodes.

  4. Verify that the scalable resource group has been created.


    # scrgadm -pv -g resource-group
    

Example – Creating a Scalable Resource Group

This example shows the addition of a scalable resource group (resource-group-1) to be hosted on two nodes (phys-schost-1, phys-schost-2). The scalable resource group depends on the failover resource group (resource-group-2) that contains the shared addresses.


# scrgadm -a -g resource-group-1 \
-y Maximum_primaries=2 \
-y Desired_primaries=2 \
-y RG_dependencies=resource-group-2 \
-h phys-schost-1,phys-schost-2
# scrgadm -pv -g resource-group-1
Res Group name:                                          resource-group-1
  (resource-group-1) Res Group RG_description:           <NULL>
  (resource-group-1) Res Group management state:         Unmanaged
  (resource-group-1) Res Group Failback:                 False
  (resource-group-1) Res Group Nodelist:                 phys-schost-1
                                                         phys-schost-2
  (resource-group-1) Res Group Maximum_primaries:        2
  (resource-group-1) Res Group Desired_primaries:        2
  (resource-group-1) Res Group RG_dependencies:          resource-group-2
  (resource-group-1) Res Group mode:                     Scalable
  (resource-group-1) Res Group network dependencies:     True
  (resource-group-1) Res Group Global_resources_used:    All
  (resource-group-1) Res Group Pathprefix:

Where to Go From Here

After you have created a scalable resource group, you can add scalable application resources to the resource group. See How to Add a Scalable Application Resource to a Resource Group for details.