DB2 VDB Refresh Fails When Upgrading from DB2 Plugin 2.5.1 to 2.6.1 (KBA5472)

Issue

When upgrading DB2 plugin from 2.5.1 to 2.6.1, after environments are refreshed, dSources and VDBs are enabled, a VDB refresh fails with the following error:

2020-02-12 Wed 08:49:17 CST        recoverDB.sh: Running db2relocatedb for DB2VDB
2020-02-12 Wed 08:49:17 CST        recoverDB.sh: Could not relocate DB DSOURCE RC: 1
2020-02-12 Wed 08:49:17 CST        recoverDB.sh: DBT1006N  The "/opt/delphix/DB2/mnts/db2_instance/DSOURCE/db2_instance/DSOURCE/opt/udb/source_instance/dsource/DATA04/db2_instance/NODE0000/DB2VDB/T0000003/C0000000.USR" file or device could not be opened.

Applicable Delphix Versions

Click here to view the versions of the Delphix engine to which this article applies

Major Release	All Sub Releases
6.0	6.0.0.0, 6.0.1.0, 6.0.1.1
5.3	5.3.0.0, 5.3.0.1, 5.3.0.2, 5.3.0.3, 5.3.1.0, 5.3.1.1, 5.3.1.2, 5.3.2.0, 5.3.3.0, 5.3.3.1, 5.3.4.0, 5.3.5.0 5.3.6.0, 5.3.7.0, 5.3.7.1, 5.3.8.0, 5.3.8.1, 5.3.9.0
5.2	5.2.2.0, 5.2.2.1, 5.2.3.0, 5.2.4.0, 5.2.5.0, 5.2.5.1, 5.2.6.0, 5.2.6.1

Resolution

The issue is caused by a bug in the DB2 2.5.1 plugin. To workaround the issue, a RESYNC (resynchronization) of the dSource is required before successful Provision. There is a plugin solution being developed to avoid the RESYNC.

The problem occurs because the dSource disable operation, required as part of the DB2 plugin upgrade, removes the <DB Name>.rstr.sql file that is found in the DB2 plugin directory on the staging host, under <DB2_plugin_directory>/DB2/logs/<dSource_Instance_name>.

In DB2 Plugin version 2.5.1 a bug removed the <DB Name>.rstr.sql file during the disable operation. The file <DB Name>.rstr.sql contains storage path information.  If the dSource was linked/configured with the Log Ingestion feature (also known as Recovery with Full Backups and Archived Logs), during a snapshot operation the plugin references this file (<DB Name>.rstr.sql) to get the storage path information. If the file is missing, the dSource snapshot metadata will not be updated with the storage path information and subsequent VDB provisioning operations will fail, unable to obtain this important information. The provisioning job fails with the error message, reiterated here for convenience:

2020-02-12 Wed 08:49:17 CST        recoverDB.sh: Running db2relocatedb for DB2VDB
2020-02-12 Wed 08:49:17 CST        recoverDB.sh: Could not relocate DB DSOURCE RC: 1
2020-02-12 Wed 08:49:17 CST        recoverDB.sh: DBT1006N  The "/opt/delphix/DB2/mnts/db2_instance/DSOURCE/db2_instance/DSOURCE/opt/udb/source_instance/dsource/DATA04/db2_instance/NODE0000/DB2VDB/T0000003/C0000000.USR" file or device could not be opened.

This issue exists in the DB2 plugin versions 2.5.1 and 2.6.0.

The bug is fixed in the DB2 plugin 2.6.1.

Anyone using the "Log Ingestion" feature of the DB2 plugin versions mentioned can experience this issue after the following actions:

1. Upgrading the plugin from 2.5.1 to 2.6.0 and due to the upgrade performed a disable/enable operation.
2. Upgrading the plugin from 2.5.1 to 2.6.1 and due to the upgrade performed a disable/enable operation.
3. Upgrading the plugin from 2.6.0 to 2.7.x and due to the upgrade performed a disable/enable operation.
4. Performed a disable/enable of a dSource with DB2 plugin 2.5.1 or 2.6.0.

The issue will be observed for all the above scenarios only in the case when the user chooses the latest snapshot (after the upgrade) to perform a provisioning operation (refresh, rollback) on the child VDB.

Troubleshooting

If you inspect the DB2 plugin log for the VDB and match the error message and you meet the other criteria already explained, then you've likely hit this issue.