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SAP IQ

Forced Recovery Steps for Coordinator

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if you are unable to start SAP IQ  Coordinator Server or  Database  in multiplex system,  check .iqmsg and .srvlog for diagnostics information, depending

on the error you might be able to recover Coordinator using  forced recovery steps. Most of the time assertion failed  error messages are SA errors. Forced

recovery will not work for SA assertion failed  error messages, you will need to restore from backups. It is advisable to contact  SAP Sybase

technical support for assistance. For IQ  issues (s_buf, freelist),  you can follow steps listed below for performing  forced recovery. For any

questions or concerns contact SAP Sybase Technical support.

Before using forced recovery, it is very important to  restrict access to the database, you can either use -gm 1(allows single connection plus

one DBA connection so that DBA can connect and drop others in case of emergency, or  issue sa_server_option('disable_connections', 'on')

after starting server in forced recovery mode, after forced recovery procedures, issue sa_server_option('disable_connections', 'off') on the same

connection.

Steps:

1. Shut down all  secondary nodes using stop_iq or stop_server.sh

2. Start Coordinator with -iqfrec , -iqmpx_sn 1 , -gn 1  and -gd 1

       start_iq -n <coordinator_server>  @params.cfg  -gd dba -gm 1 -iqfrec <coord db name without .db extn> -iqmpx_sn 1  <coord db name with .db extn>

      start_iq  -n < coordinator_server>  @params.cfg  -gd dba  -gm 1 -iqfrec  coord -iqmpx_sn 1 coord.db

3. Forced recovery marks all allocation within database as in use, run sp_iqcheckdb in  dropleaks mode to reset allocation map to correct

state.

            set temporary option dbcc_log_progress='on' ;

            sp_iqcheckdb 'dropleaks database';

    If there are no errors and sp_checkdb displays message 'Freelist Updated'  you have recovered leaked blocks.  Continue to Step 4

   if incosistency is found, follow the instructions for dropping inconsistent indexs/tables or columns to drop inconsistent objects in Administration:

   Backup, Restore and Data Recovery (Chapter: System Recovery and Database Repair)

             http://infocenter.sybase.com/help/topic/com.sybase.infocenter.dc01759.1601/doc/pdf/iqbackup.pdf

4.  Issue Checkpoint

5. Shutdown Coordinator using stop_iq or stop_server.sh script

6.  Restart Coordinator normally without -iqfrec, -iqmpx_sn 1 , -gd 1 and -gm 1 switches

          ./start_server.sh

      Note:  start_server.sh and stop_server.sh scripts are generated by Sybase Control Center in  Server .db directory.

7.  If corruption was in IQ_SYSTEM_MAIN then run_sp_iqcheckdb on IQ_SYSTEM_MAIN else run dbcc on entire database.

           set temporary option dbcc_log_progress='on' ;

           sp_iqcheckdb 'verify dbspace IQ_SYSTEM_MAIN';

           sp_iqcheckdb 'verify database'

8.  Synchronize Secondary Nodes.

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