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Title
Shareplex complains about log wrap on one of the RAC instances which was kept down for a long tim -
Description
Shareplex complains about log wrap on one of the RAC instances which was kept down for a long time and is recently brought up. Earlier it was kept down and its archive logs removed while Shareplex ran on other RAC instances fine. The problem only occurred when this problem instance was brought online with the result that Capture is not processing redologs for any of the RAC instances including this problem instance.
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Cause
When the problem RAC instance is brought online, missing archive logs will interfere with Shareplex’s Capture process.
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Resolution
So long as it was kept offline, there were no issues and Shareplex did not care about the log wrap. However, the moment it is brought online, Shareplex needed the old archive logs it needed to process based on the entry in shareplex_actid table. Going forward, Capture needs to be pointed to the currently available archive log for that instance otherwise it will not process changes for any of the nodes including the problem node. The following is the procedure to point Capture to the currently available archive/online redo log:
Here is the procedure to point Capture to the next available archive log:
1. Issue "list config" on source sp_ctrl to determine the current activation ID. For example, in the following output, the current activation ID is 10 (the # after conf.) :
sp_ctrl (tispadb1:2100)> list config
File Name State Datasource
-------------------------------------------------- ----------
---------------
test_xxx_090820 Active o.ACOSDB
Last Modified At: 20-Aug-09 03:58 Size: 335 Internal Name: .conf.10
2. Shutdown source Shareplex and execute the following SQL in the source database:
UPDATE shareplex_actid SET seqno = < new log that is present on disk>, offset = 0, log_start_offset=0 WHERE actid = <current activation id > AND instance_name='<appropriate instance name>';
commit;
3. Restart Shareplex and Capture.