Each messaging engine establishes an exclusive
lock on its data store. While the messaging engine is running, it
maintains that lock to ensure the integrity of the data within the
data store.
Compare
your symptoms with those listed in the following table and examine
the possible solutions:
Symptom |
Cause |
Solution |
The messaging engine cannot start nor
failover to another server. The messaging engine writes error
message CWSIS1519 |
The messaging engine cannot connect to the database that
you specified in the data source that you configured to enable the
messaging engine to access its data store. |
|
After a delay of many minutes, the messaging engine cannot
failover to another server and writes error message CWSIS1519. |
Another instance of the same messaging engine is holding
the data store lock, or the database has not released a data store
lock that was held by a failed instance of the same messaging engine. |
- If you can connect to the database, another instance of the messaging
engine might hold a lock on the data store. Check for other running
instances of the same messaging engine. Only one instance of each
messaging engine can run in a cluster at a given time.
- After the failure of an instance of a messaging engine or an application
server that is running in a cluster, the database might not have released
the database locks that comprise the data store lock. Use the administration
tools for your relational database management system to examine the
locks on the SIBOWNER table.
If the database is still holding locks after the failure of a server,
ensure that you configure the liveness checking of the network connection
between the application server and the database server to enable prompt
failover. For example, examine the TCP keep alive parameter.
If you are using DB2 for z/OS, you can examine the DB2 Idle Thread Timeout.
You
might need to use your database administration tools to force the
release of the lock on the data store.
|
The messaging engine fails to start and writes error messages CWSIS1535 and CWSIS1519 |
The identifiers in the SIBOWNER table
do not match those of the messaging engine. |
- Check that the data source that you configured for the messaging
engine refers to the correct database.
- If the MEUUID identifiers do not match, check
that a previous messaging engine did not use the same tables. If the
tables already exist, DROP the tables and CREATE
them again for the new messaging engine.
- If the INCUUID identifiers do not match,
another instance of the same messaging engine is running and has acquired
the lock. Check for other running instances of the messaging engine.
|
The messaging engine starts but then stops and writes error
message CWSIS1519. |
The messaging engine has lost its lock on the data store. |
- Check that you have connectivity to the database through the data
source that you specified. The messaging engine might have lost network
connectivity and be unable to maintain a connection with the database.
- If you can connect to the database, another instance of the messaging
engine might have started and obtained a lock on the data store. Check
for other running instances of the messaging engine.
|