How to change the hostname in the IBM Rational ClearCase environment

Making the task easier

Mallikarjuna Manoj Kandala
Published on March 24, 2015

This article shows how to make changes to various server components of the IBM® Rational® ClearCase® environment, when the hosted system hostname changes. The content in this article applies to Rational ClearCase v8.0.0.x and higher, and only UNIX and Linux systems.

You will learn how to make changes to Rational ClearCase server components, including:

• Registry
• License
• VOB
• View
• CCRC WAN
• IBM® Rational® ClearCase MultiSite®

How to update various server components

Before you make any changes, capture the IBM Rational ClearCase host information. Use the command: cleartool hostinfo -l to retrieve information about the license and registry server.

License server changes:

IBM Rational ClearCase supports two types of licenses, the Rational Common Licensing (FlexLM) and the Classic Atria licensing. Update these files with the new host name:

Rational common licensing (FlexLM):
/var/adm/rational/clearcase/config/flexlm_host

Rational ClearCase Classic/Atria licensing:
/var/adm/rational/clearcase/config/license_host

Registry server changes

When the host name of the VOB and/or View Servers is going to be changed, many changes must occur in the respective registry server. Some of the changes include the storage locations of:

• VOBs and views
• VOB objects and tags
• View objects and tags

Before you can update the host name in the Rational ClearCase registry, you need the registry password and the VOB and view names. You can reset the registry password using: /opt/rational/clearcase/etc/rgy_passwd

To find the list of VOBs which are impacted because of hostname change:
cleartool lsvob -long -host <current hostname of the system on which you are planning to change hostname>

To find the list of views which are impacted because of hostname change:
cleartool lsview -long -host <current hostname of the system on which you are planning to change hostname>

To update the hostname in the registry of:

1. VOB objects, cleartool register command to be used with the parameters -vob -replace.
   For example :
   /opt/rational/clearcase/bin/cleartool register -vob -replace -host <New Fully Qualified Domain Name (FQDN) of the host> -hpath /net/project/clearcase/vobstg/vob_tag_name.vbs /net/project/clearcase/vobstg/vob_tag_name.vbs
2. VOB tags, cleartool mktag command to be used with the parameters -vob -replace.
   For example:
   /opt/rational/clearcase/bin/cleartool mktag -vob -replace -tag /vobs/vob_tag_name -public -password rgy_passwd -host <New Fully Qualified Domain Name (FQDN) of the host> –gpath /net/project/clearcase/vobstg/vob_tag_name.vbs /net/project/clearcase/vobstg/vob_tag_name.vbs"
3. View objects, cleartool register command to be use with the parameters -view -replace
   For example:
   "/opt/rational/clearcase/bin/cleartool register -view -replace -host <New Fully Qualified Domain Name (FQDN) of the host> -hpath /net/project/clearcase/vobstg/view_tag_name.vbs /net/project/clearcase/vobstg/view_tag_name.vbs"
4. View tags, cleartool mtag command to be used with the parameters -view –replace
   For example:
   /opt/rational/clearcase/bin/cleartool mktag -view -replace -tag view_tag_name -host <New Fully Qualified Domain Name (FQDN) of the host> –gpath /net/project/clearcase/vobstg/view_tag_name.vbs /net/project/clearcase/vobstg/view_tag_name.vbs

Note:
The ClearCase Knowledge Center lists the common commands for each environment.

VOB and View server process updates inside the storage location

After you make the host name changes, reboot the system. During the shutdown phase, all vob_server processes are stopped. After the system startup, all of the Rational ClearCase services and all vob_server processes starts. Verify that the updated information is inside the VOB storage location. Most teams use this storage location path convention: /<VOB_STORAGE_SHARE_MOUNT_POINT>/<VOB_STORAGE_DIRECTORY>/VOB_TAG.vbs/. Use the cleartool lsvob command to obtain VOB storage directory information of each VOB. Verify that the .pid and .hostname files are updated before the development environment is made available to your team. To verify, make sure the:

• .pid file contains the active vob_server process ID of the respective VOB
• .hostname contains the new hostname information

This same process is also applicable for the view_server processes. You can find the view storage directory information of each view using the cleartool lsview command.

CCRC WAN server changes:

To host the CCRC Wide Area Network (WAN) server component on the Rational ClearCase host:

• Separately install IBM WebSphere Application Server (WAS) and IBM HTTP Server (IHS).
• Use the Modify option in IBM Installation Manager to uninstall only the CCRC WAN server component from the current Rational ClearCase installation (as opposed to uninstalling all the components).
• Use the Uninstall option in IBM Installation Manager to uninstall the IBM WebSphere Application Server (WAS) and IBM HTTP Server (IHS).
• Use the Install option in Installation Manager to reinstall IBM WebSphere Application Server and IBM HTTP Server.
• Create the WAS profile (name the profile ccrc).

Start the CCRC WAN Server component installation again using the Modify option in Installation Manager. During the installation, please use the path of the ccrc profile created above in the last bulleted item. These steps restart the Rational ClearCase server processes.

CCRC/CTE client level changes:

Because of the hostname changes of the CCRC WAN Server, you need to update the current Clear Team Explorer (formerly called ClearCase Remote Client) Web Views (CTE/CCRC Web Views) URL. This has to be done before you can use existing views again after the system hostname change.

To update the current CTE/CCRC Web View URL:

1. Open the Clear Team Explorer
2. Expand the My Views section
3. Select Web view
4. Right-click on the Web view and select the popup menu item Update URL...

Figure 1. Clear Team Explorer dialog to update the host name

View image at full size

IBM Rational ClearCase MultiSite server changes

In the MultiSite replicated VOBs, in order to update the hostname information in all sites, the Administrator must identify the master replica site first. To do this, use the multitool lsreplica –long command. Complete the hostname correction at the master replica site. Send the same information need to other replica(s) via packets. Import the sync packets at other site(s). For more information about the IBM Rational ClearCase MultiSite commands, please see the knowledge center.

Follow these steps to update the new host name information in the all replicas:

1. Run the multitool chreplica command at the master replica site.
   Eg: multitool chreplica –host new.hostname replica_name@vob_tag
2. Sync the replica with -export option at the master replica site
   Eg: multitool syncreplica -export -fship replica_name@/vobs/vob_tag
3. Sync the replica with -import option at the other sites (s)
   Eg: multitool syncreplica -import -receive
4. Verify the hostname in Source and Destination Sites with the multitool lsreplica command, by ensuring the present working directory to be the respective VOB tag directory

IBM Rational ClearCase client level changes

UNIX/Linux clients:

Update the new registry server's host name in the file /var/adm/rational/clearcase/config/rgy_svr.conf

Update the License Server using the instructions in the server configuration guidelines.

Windows clients:

Update the new registry and license server hostname information using the IBM Rational ClearCase control panel located under the Windows control panel.

Conclusion

Hostname changes are not very common in the infrastructure, but sometimes they cannot be avoided. The steps in this article should help you handle the changes gracefully.

Downloadable resources

• PDF of this content

Related topics

• Read "Move IBM Rational ClearCase server to a new domain in Windows", developerWorks, August 29, 2014, Koichiro Hideura.
• For more information about Rational ClearCase, check the product overview page.
• Try IBM Bluemix, the cloud platform that helps developers rapidly build, manage and run web and mobile applications.
• Download a free trial version of Rational software.