3.3. Updating an Existing Installation

Updating a existing Red Hat HPC cluster is a two step process. The installer node contanins a Red Hat repository for RHEL 5. This repository must first be updated prior to updating the kits or running a yum update on the master installer. If the master installer contains packages that are newer than the packages in the Kusu repository, there can be dependency problems when installing some kits. See chapter 4 on how to update the repository.

Once the repository is updated the kits on the installer can be updated. Before the base kit can be updated, the existing addon kits in the RHHPC system must be removed. This is required as some of the older kits are not guaranteed to be compatible with RHHPC 5.3. The updated versions of the addon kits for RHHPC 5.3 must be installed.

To update kits please follow the instructions below.

Procedure 3.1. Removing Incompatible_Kits Prior to Updatin _the Base Kit

Remove the kit components from the nodegroup. Run ngedit and select the installer node group to edit. Go to the component screen. De-select the components of the kits you wish to upgrade. Continue and apply the changes.
Run the above step for all nodegroups.
Remove the kit associations from the repository.
```
#repoman -e -kkitname -rreponame
```
Optionally, to list repositories and associated kits, the following command can be used:
```
#repoman -l
```
Update repository after removing kit associations:
```
#repoman -u -rreponame
```
Remove older kits from the system.
```
#kitops -e -kkitname
```
Optionally use this command to list installed kits.
```
#kitops -l
```

The base kit must be updated prior to reinstalling the other kits. The steps below outline how to update the base kit on the installer.

Procedure 3.2. Updating the Base Kit Prior to Other Kits

Ensure that the installer node can connect to Red Hat Network (RHN).
Update the ocs package:
```
# yum update ocs
```
Source the environment:
```
# source /etc/profile.d/kusuenv.sh
```
Run the OCS upgrade script. This will update the base kit from RHN, and rebuild the repository for installing nodes.
```
# ocs-setup -u
```

The base kit is now updated. If desired the other kits can be updated. Use the following procedure to update the kits:

Procedure 3.3. Updating Other Kits

Update the kit downloaders by running the following command for the downloader you wish to upgrade
```
#yum update ocs-kit-kitname
```
Follow the instructions in chapter 5 for installing kits

Warning

There is a known issue in upgrading the Cacti kit from Red Hat Enterprise Linux HPC Solution 5.2 to 5.3. The cacti user must be removed prior to adding the new cacti kit.

Use: userdel cacti to remove the user.

Note

There is a known issue whereby the ocs-setup -u command does not proceed and fails with the message OCS setup script does not seem to have run in this machine, cannot upgrade. To work around this, perform the following:

# touch /var/lock/subsys/ocs-setup