Power HA migration

powerha migration detailed document

If anyone has any problems or need any help to perform the powerha migration, you can refer to the below document, which clearly illustrates how to perform the migration.

PROCEDURE :

Prework : (atleast 2 days before the actual migration)

(1)Check current version of HACMP is up and the cluster is stable.

# odmget HACMPcluster

# lssrc –ls clstrmgrES | grep state

(2) Verify the existing cluster and correct the problem if any error found

(3) Take the mksysb backup and also the copy of the below important files

     Save a copy of these files:

         /.rhosts

        /etc/hosts

          /etc/exports

        /etc/inittab

    Save a copy of these files

          /usr/es/sbin/cluster/netmon.cf

          /usr/es/sbin/cluster/etc/exports

          /usr/es/sbin/cluster/etc/rhosts

        /tmp/hacmp.log


 

(4) Take snapshot and save it to locally /tmp, and another copy in safest place like NIM server

(5)Take the clone for the rootvg disk on each server on the spare disk(extra luns should be mapped for taking the clone if it is not present) to ensure safer backout.If any issue comes, the server will be booted with this disk.

(6)Download all the requisite filesets, for the HA migration

Migration Procedure

Lets assume the one pair of participating cluster node as node1 and node2

Step 1: Stop Cluster Services on a Node Hosting the Application ( node1)

stop cluster services on node node 1 using the graceful with takeover option. (this is known as stopping cluster services and moving the resources groups to other nodes - .i.e node2 )

1.Enter smit hacmp

2.Use the System Management (C-SPOC) > Manage HACMP Services > Stop Cluster Services SMIT menu to stop cluster services.

3.Select takeover for Shutdown mode.

4.Select local node only and press Enter.

Now resource group containing the MQ to fall over to node node2 and verify it by

1] clRGinfo /usr/es/sbin/cluster/utilities/clRGinfo

2] execute command hostname

3] check with application team that application is running & all MQ channels are available

Step 2: Install the HACMP software

On node node1, install HA 6.1 filesets, which converts the previous HACMP configuration database (ODMs) to the desired format. This installation process uses the cl_convert utility and creates the /tmp/clconvert.log file. A previously created version of the file is overwritten.

To install the HACMP software:

#cd to the directory that contains filesets

1.Enter smit install

2.In SMIT, select Install and Update Software > Update Installed Software to Latest Level (Update All) and press Enter.

3.Enter the values for Preview only? and Accept new license agreements? For all other

field values, select the defaults.

Preview only select No

Accept new license agreement select Yes

4) Press enter

Step 3: Start Cluster Services on the Upgraded Node

Start cluster services on node node1.

To start cluster services on a single upgraded node:

1.Enter smit clstart

2.Enter field values as follows and press Enter

Start now, on system restart or both	Select now
Start Cluster Services on these nodes	Select local node (Default)
Manage Resource Groups Automatically/Manually	Select Automatically HACMP brings resource group(s) online according to the resource groups’ configuration settings and the current cluster state, and starts monitoring the resource group(s) and applications for availability.
BROADCAST message at startup?	Select false
Startup Cluster Information Daemon?	Select true
Ignore verification errors?	Select false

Automatically correct errors found during cluster start?

Whatever value is in these fields will not make sense since it is a mixed cluster.

Note:Verification is not supported on a mixed version cluster. Run verification only when all nodes have been upgraded.

Step 4: Repeat the same steps for the node2

Step 5 :Verifying the Upgraded Cluster Definition

After the HACMP 6.1 software is installed on all of the nodes in the cluster and cluster services restored, verify and synchronize the cluster configuration. Verification ensures that the cluster definition is the same on all nodes. You can verify and synchronize a cluster only when all nodes in the cluster are running the same version of the software. 

 

To verify the cluster:

1.Enter smit hacmp

2.In SMIT, select Extended Configuration > Extended Verification and Synchronization > Verify Changes only and press Enter.

Verifying Software Levels Installed Using AIX 5L Commands

Run the commands lppchk -v and lppchk -c “cluster.*”

Both commands return nothing if the installation is OK.

perform the another failover to check the RG movement after the upgrade on both nodes.

How to Backout if anything goes wrong :

Boot the server with the clone disk in case of any issue