A storage migration can cause a major outage on your database which is never a good idea.
If your ASE system is using RAW devices we can reduce our outage by using the mirror command.
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Sybase
Invalid RSI Locater
If the RSI locaters at the primary and replicate Replication Servers are not identical, then the primary Replication Server might delete messages from its stable queue at an incorrect location and invalidate the RSI locater at the replicate Replication Server.
RSI locaters must be identical. If they are not identical you need to reset the correct entry in the rs_locater system table in the Replication Server System Database (RSSD)
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Starting ASE after a system kill
Killing ASE with a SIGKILL is obviously not a good idea but you can run out of other options.
Data-loss can and will happen because no checkpoint will be given to the database.
Should it unavoidable you need to check some actions before starting such as the shared memory segments and files.
The shared memory files are located under the $SYBASE/$SYBASE_ASE directory with the SERVER_NAME.krg file name. The sybase process should be able to read and write in this file.
Shared memory segments also need to be cleaned up. These can be identified with ipcs | grep sybase and ipcrm -M <KEY>...
Sybase ASE last full database backup
Sybase Replicated database copy
Refreshing a Primary Database of a Replication setup into DEV/QA.
When we load a replicated database into another ASE server, it will not jump online due to the secondary truncation point that was set in the source database. In other words after the load is completed, when you issue the online database command it will fail due to the secondary truncation point that was used by the replication agent.
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Sybase SQSH
Sybase ASE performance tuning
Check performance
We can check the performance of the ASE engine by using the sp_sysmon procedure. This procedure will monitor the engine for the given time spew out a long report. This allows us to see our performance and adjust the engine where needed.
Sometimes sp_sysmon gives a direct recommendation at the bottom which is always good to looking to.
Of course it helps to start sp_sysmon when the database is under high load.
Type
Command
Data cache
sp_sysmon "00:05:00" , dcache;
Procedure cache
sp_sysmon "00:05:00" , pcache;
Memory
sp_sysm...