MQ Tables COLD restart

Products

• CA Automic Workload Automation - Automation Engine

Issue/Introduction

MQ Tables COLD restart 

Resolution

Detailed Description and Symptoms

 

We are preparing for a Disaster Recovery test and want to know what we might need to prepare the database. 

Investigation

MQ stands for "Message Queue".  The Message Queue tables basically act as a work space for all of the information traveling between Automic components. 

There are 14 MQ tables in v9 and v10

• MQCP001
• MQCP002
• MQCP003
• MQCP004
• MQCP005
• MQDWP
• MQLS
• MQMEM
• MQPWP
• MQSRV
• MQWP
• MQQWP
• MQOWP
• MQRWP

15 MQ tables in v11.1 (one more table because the JWP has been introduced)

• MQCP001
• MQCP002
• MQCP003
• MQCP004
• MQCP005
• MQDWP
• MQJWP
• MQLS
• MQMEM
• MQOWP
• MQPWP
• MQQWP
• MQRWP
• MQSRV
• MQWP

26 tables in version 11.2 and v12 because of the Zero Downtime Upgrade:

• MQ1CP001
• MQ1CP002
• MQ1CP003
• MQ1CP004
• MQ1CP005
• MQ2CP001
• MQ2CP002
• MQ2CP003
• MQ2CP004
• MQ2CP005
• MQ1DWP
• MQ1JWP
• MQ1OWP
• MQ1PWP
• MQ1QWP
• MQ1RWP
• MQ1WP
• MQ2DWP
• MQ2JWP
• MQ2OWP
• MQ2PWP
• MQ2QWP
• MQ2RWP
• MQ2WP
• MQLS
• MQMEM
• MQSRV

 
Sometimes, old messages can be left in the MQ tables causing the Automic system to not be able to start correctly, or freeze.  The most common reason for this is if the Automic system has been brought down ungracefully.  The best example is if the server that Automic is on has been rebooted or crashed unexpectedly as in a Disaster Recovery (DR) scenario.
When the machine stops suddenly, the messages in the MQ tables are left.  When Automic attempts to start the system in "Normal" mode, it will try and process these messages.  Because they may no longer have valid information, the WPs or CPs will not connect properly and the system will be unable to start.

Solution

In most cases, a "Cold" restart is done either by setting the startmode=COLD in the ucsrv.ini file or by right-clicking the WP process in Service Manager Dialog and selecting "Start Service with" > "Coldstart"
 

This should clear the MQ tables.  However, because of potential database issues (locked tables, etc.) you still may not be able to start your system.  You can select from the MQ tables to confirm that there are records left in these tables.
If this is the case, you will have to truncate from the MQ tables. Please contact support for the commands to perform this action.

Additional Information

Per default the COLDSTART procedure is not executed against the MQSRV table..

If for a particular reason the purging of this time is required, for example as suggested by BROADCOM support and a Consultant team, the troncation of this table must be done manually by a DBA or by an experienced user.

Either by calling the stored procedure 'UC_Truncate_Table' dedicated to the COLDSTART applied to the  MQSRV table

call UC_Truncate_Table('MQSRV')

or 

Truncate table MQSRV.