How to Remove a Node From a Resource Group

This procedure contains the following sections.

• How to Remove a Node From a Scalable Resource Group

• How to Remove a Node From a Failover Resource Group

• How to Remove a Node From a Failover Resource Group That Contains Shared Address Resources

• Example – Removing a Node From a Resource Group

To complete these procedures, you must supply the following information.

• node names and node IDs of all of the cluster nodes

  # scconf -pv | grep “Node ID”

• name(s) of the resource group or groups from which you plan to remove the node

  # scrgadm -pv | grep “Res Group Nodelist”

• names of the IP Networking Multipathing groups that will host the network resources that are used by the resource group(s) on all of the nodes

  # scrgadm -pvv | grep “NetIfList.*value”

Additionally, be sure to verify that the resource group is not mastered on the node that you will remove. If the resource group is mastered on the node that you will remove, run the scswitch command to switch the resource group offline from that node. The following scswitch command will bring the resource group offline from a given node, provided that new-masters does not contain that node.

# scswitch -z -g resource-group -h new-masters

-g resource-group

Specifies the name of the resource group (mastered on the node that you will remove) that you are switching offline.

-h new-masters

Specifies the node(s) that will now master the resource group.

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

If you plan to remove a node from all of the resource groups, and you use a scalable services configuration, first remove the node from the scalable resource group(s). Then, remove the node from the failover group(s).

How to Remove a Node From a Scalable Resource Group

A scalable service is configured as two resource groups, as follows.

• One resource group is a scalable group that contains the scalable service resource.

• One resource group is a failover group that contains the shared address resources that the scalable service resource uses.

Additionally, the RG_dependencies property of the scalable resource group is set to configure the scalable group with a dependency on the failover resource group. See Appendix A, Standard Properties for details on this property.

See the Sun Cluster 3.1 Concepts Guide document for details about scalable service configuration.

Removing a node from the scalable resource group causes the scalable service to no longer be brought online on that node. To remove a node from the scalable resource group, perform the following steps.

1. Remove the node from the list of nodes that can master the scalable resource group (the nodelist resource group property).

   # scrgadm -c -g scalable-resource-group -h nodelist

   -c

   Changes a resource group.

   -g scalable-resource-group

   Specifies the name of the resource group from which the node is being removed.

   -h nodelist

   Specifies a comma-separated list of nodes that can master this resource group.

2. (Optional) Remove the node from the failover resource group that contains the shared address resource.

   See How to Remove a Node From a Failover Resource Group That Contains Shared Address Resources for details.

3. (Optional) Update the Load_balancing_weights property of the scalable resource to remove the weight of the node that you want to remove from the resource group.

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

How to Remove a Node From a Failover Resource Group

Perform the following steps to remove a node from a failover resource group.

If you plan to remove a node from all of the resource groups, and you use a scalable services configuration, first remove the node from the scalable resource group(s). Then, use this procedure to remove the node from the failover group(s).

If the failover resource group contains shared address resources that scalable services use, see How to Remove a Node From a Failover Resource Group That Contains Shared Address Resources.

1. Update the node list to include all of the nodes that can now master this resource group.

   This step removes the node and overwrites the previous value of the node list. Be sure to include all of the nodes that can master the resource group here.

   # scrgadm -c -g failover-resource-group -h nodelist

   -c

   Changes a resource group.

   -g failover-resource-group

   Specifies the name of the resource group from which the node is being removed.

   -h nodelist

   Specifies a comma-separated list of nodes that can master this resource group.

2. Display the current list of IP Networking Multipathing groups that are configured for each resource in the resource group.

   # scrgadm -pvv -g failover-resource-group | grep -i netiflist

3. Update netiflist for network resources that the removal of the node affects.

   This step overwrites the previous value of netiflist. Be sure to include all of the IP Networking Multipathing groups here.

   # scrgadm -c -j network-resource -x netiflist=netiflist

   ---

   Note –

   The output of the preceding command line identifies the nodes by node name. Run the command line scconf -pv | grep “Node ID” to find the node ID.

   ---

   -c

   Changes a network resource.

   -j network-resource

   Specifies the name of the network resource that is hosted on the netiflist entries.

   -x netiflist=netiflist

   Specifies a comma-separated list that identifies the IP Networking Multipathing groups that are on each node. Each element in netiflist must be in the form of netif@node. netif can be given as an IP Networking Multipathing group name, such as sc_ipmp0. The node can be identified by the node name or node ID, such as sc_ipmp0@1 or sc_ipmp@phys-schost-1.

   ---

   Note –

   Sun Cluster does not currently support using the adapter name for netif.

   ---

4. Verify the updated information.

   # scrgadm -pvv -g failover-resource-group | grep -i nodelist # scrgadm -pvv -g failover-resource-group | grep -i netiflist

How to Remove a Node From a Failover Resource Group That Contains Shared Address Resources

In a failover resource group that contains shared address resources that scalable services use, a node can appear in the following locations.

• the node list of the failover resource group

• the auxnodelist of the shared address resource

To remove the node from the node list of the failover resource group, follow the procedure How to Remove a Node From a Failover Resource Group.

To modify the auxnodelist of the shared address resource, you must remove and recreate the shared address resource.

If you remove the node from the failover group's node list, you can continue to use the shared address resource on that node to provide scalable services. To do so, you must add the node to the auxnodelist of the shared address resource. To add the node to the auxnodelist, perform the following steps.

You can also use the following procedure to remove the node from the auxnodelist of the shared address resource. To remove the node from the auxnodelist, you must delete and recreate the shared address resource.

1. Switch the scalable service resource offline.

2. Remove the shared address resource from the failover resource group.

3. Create the shared address resource.

   Add the node ID or node name of the node that you removed from the failover resource group to the auxnodelist.

   # scrgadm -a -S -g failover-resource-group\ -l shared-address -X new-auxnodelist

   failover-resource-group

   The name of the failover resource group that used to contain the shared address resource.

   shared-address

   The name of the shared address.

   new-auxnodelist

   The new, modified auxnodelist with the desired node added or removed.

Example – Removing a Node From a Resource Group

This example shows how to remove a node (phys-schost-3) from a resource group (resource-group-1), which contains a logical hostname resource (schost-1).

# scrgadm -pvv -g resource-group-1 | grep -i nodelist
(resource-group-1) Res Group Nodelist:       phys-schost-1 phys-schost-2 
                                             phys-schost-3
# scrgadm -c -g resource-group-1 -h phys-schost-1,phys-schost-2
# scrgadm -pvv -g resource-group-1 | grep -i netiflist
(resource-group-1:schost-1) Res property name: NetIfList
(resource-group-1:schost-1:NetIfList) Res property class: extension
(resource-group-1:schost-1:NetIfList) List of IP Networking Multipathing 
interfaces on each node
(resource-group-1:schost-1:NetIfList) Res property type: stringarray
(resource-group-1:schost-1:NetIfList) Res property value: sc_ipmp0@1 sc_ipmp0@2
                                                          sc_ipmp0@3

(sc_ipmp0@3 is the IP Networking Multipathing group to be removed.)

# scrgadm -c -j schost-1 -x netiflist=sc_ipmp0@1,sc_ipmp0@2
# scrgadm -pvv -g resource-group-1 | grep -i nodelist
(resource-group-1) Res Group Nodelist:       phys-schost-1 phys-schost-2
# scrgadm -pvv -g resource-group-1 | grep -i netiflist
(resource-group-1:schost-1:NetIfList) Res property value: sc_ipmp0@1 sc_ipmp0@2