How to Remove a Node from an HACMP Cluster

Contents

1. Introduction
2. STEP 1: Stop the Cluster Services on the Second Node
3. STEP 2: Remove the Node from all Resource Groups
4. STEP 3: Remove the Node from the Cluster
5. STEP 4: Verify and Synchronize Cluster

1. Related Information

Introduction

This article describes how to remove a node from an HACMP cluster. We find the following situation:

node01# clRGinfo

-----------------------------------------------------------------------------

Group Name     Group State                  Node           

-----------------------------------------------------------------------------

RES_GRP_01     ONLINE                       node01        

               OFFLINE                      node02        

RES_GRP_02     ONLINE                       node01        

               OFFLINE                      node02        

Conclusion: node02 is member of two resource groups, but all resources are active on node01.

STEP 1: Stop the Cluster Services on the Second Node

We need to release all resources from the node we want to remove from the cluster. If there are any resources active we have to move the resources to the next priority node. In this example (see above) node02 has no active resources so we can select Bring Resource Groups Offline here:

node02# smitty clstop

                                     Stop Cluster Services

Type or select values in entry fields.

Press Enter AFTER making all desired changes.

                                                        [Entry Fields]

* Stop now, on system restart or both                 now                                          +

  Stop Cluster Services on these nodes               [node02]                                      +

  BROADCAST cluster shutdown?                         false                                        +

* Select an Action on Resource Groups                 Bring Resource Groups Offline                +

STEP 2: Remove the Node from all Resource Groups

node01# smitty hacmp

  -> Extended Configuration

    -> Extended Resource Configuration

      -> HACMP Extended Resource Group Configuration

        -> Change/Show a Resource Group

                                  Change/Show a Resource Group

Type or select values in entry fields.

Press Enter AFTER making all desired changes.

                                                        [Entry Fields]

  Resource Group Name                                 RES_GRP_01

  New Resource Group Name                            []

  Participating Nodes (Default Node Priority)        [node01]                                      + <=== remove node02 from the list ==

  Startup Policy                                      Online On Home Node Only                     +

  Fallover Policy                                     Fallover To Next Priority Node In The List   +

  Fallback Policy                                     Never Fallback                               +

Remove node02 from the list of participating nodes. Repeat this step for all resource groups with node02 as partitipating node.

STEP 3: Remove the Node from the Cluster

node01# smitty hacmp

  -> Extended Configuration

    -> Extended Topology Configuration

      -> Configure HACMP Nodes

        -> Remove a Node in the HACMP Cluster

          -> Select node02

                                    Configure HACMP Nodes

Move cursor to desired item and press Enter.

  Add a Node to the HACMP Cluster

  Change/Show a Node in the HACMP Cluster

 >Remove a Node in the HACMP Cluster<

STEP 4: Verify and Synchronize Cluster

node01# smitty hacmp

  -> Extended Configuration

    ->  Extended Verification and Synchronization

Job done: clRGinfo now shows one node less:

node01# clRGinfo

-----------------------------------------------------------------------------

Group Name     Group State                  Node           

-----------------------------------------------------------------------------

RES_GRP_01     ONLINE                       node01        

RES_GRP_02     ONLINE                       node01