Hi, this is Sharath and I work for the WebSphere Process Server support team. We have seen quite a few customers migrating from V6.x to V7.0 and this post is an effort to explain some of the pre-migration considerations through post-migration verification to make the overall migration experience a sweet one. As you may be aware, migration can be very complex and time consuming. I hope this post helps you avoid some of the pitfalls.
I have split the Migrating posts into 4 parts to keep it simple and compact. I will focus on a typical ND golden topology on DB2. We would love to hear your feedback and appreciate you sharing your own experience with us.
Before migration, you need to perform some environment verification and backup the whole environment. Follow the recommended steps below:
1) Check the SystemOut.log, there should be no errors or warning messages in the logs. If you find any unexpected errors, then resolve them before migration.
2) Source profile snapshot directory
The configuration files in the profile to be migrated are copied during the migration procedure to a snapshot directory that then becomes the source for the profile migration. The directory is an optional parameter for the BPMSnapshotSourceProfile command ( explained in part-2 ) or a configurable value in the BPM profile migration wizard.
Prior to migration, verify that sufficient storage for the snapshot directory exists. The storage requirements can be estimated by adding up the following:
- Sizes of the profile configuration information to be migrated:
- profile_root/installableApps directory
- profile_root/installedApps directory
- profile_root/config directory
- profile_root/properties directory
- Size of the shared libraries to be migrated:
- Shared libraries referenced in the libraries.xml configuration files
- If trace is enabled, allocate an additional 500MB (depends on the size and complexity of your configuration) for the trace file written to the snapshot directory.
3) Set Ulimit to 8192. On UNIX systems, this helps to avoid errors during migration due to too many open files based on the size and complexity of the cell and applications.
4) Set JVM heap size parameters as per technote: OutOfMemoryError PermGen space errors in WebSphere Process Server migration wizard.
5) Set com.ibm.ssl.enableSignerExchangePrompt to false in profile_home/properties/ssl.client.props file to avoid WASPostUpgrade wait infinitely for username/password to be entered.
For details - refer to the Information Center topic Changing the signer auto-exchange prompt at the client.
6) Set com.ibm.SOAP.requestTimeout=1800 in profile_root/properties/soap.client.props file to avoid possible connection-timeout. For details - refer to the Information Center topic Migrating a large WebSphere Application Server, Network Deployment configuration with a large number of applications.
7) Backup the WebSphere Process Server V6.2 environment
Backup the WebSphere Process Server V6,2 environment before migration in case a roll back is necessary.
There are two ways to do this:
a. Backup the full WebSphere Process Server V 6.2 installation directory, depending on your platform, on Windows, backup the directory as a zip file; on Unix, use “tar -cvf” command to backup the directory. When you need to restore the environment, just delete the old one and unzip the backp file.
b. Run the backupConfig command to back up configuration files for dmgr and every node. The space available for the config backup directory should be at least the size of the source profile’s configuration directory and applications. The command syntax is as follows:
backupConfig <backup_file> [options]
backupConfig <backup_file> -profileName profile_name
Where backup_file specifies the file to which the backup is written
profile_name defines the profile name in a multi-profile installation
8) Backup the databases
Backup the databases used by WebSphere Process Server and those used for deployed applications.
Backup the following databases that are configured by any of the migration source profiles according to the documentation for your databases:
9) Backup the .nifRegistry file
Note: Backup database and configuration at the same time to keep transaction logs in Sync with the db.
- Business Process Choreographer Database
- Business Space database
- Common database
- Common Event Infrastructure Database
- Messaging Engine Database
The .nifRegistry file identifies the installation root for all installed WebSphere Process Server products. It also identifies the installation root for all installed WebSphere Application Server products. It is located at the following: