Recovering the administrative task scheduler task list

Two redundant, active copies of the task list exist to protect your system in case there is a media failure. Console message DSNA679I indicates that one of these copies is not accessible. If this happens, you can recover the task list.

About this task

One copy of the task list is a shared VSAM data set, by default DSNC910.TASKLIST, where DSNC910 is the Db2 catalog prefix. The other copy is stored in the table ADMIN_TASKS in the SYSIBM schema. Include these redundant copies as part of your backup and recovery plan.

Tip: If Db2 is offline, message DSNA679I displays on the console. As soon as Db2 starts, the administrative task scheduler performs an autonomic recovery of the ADMIN_TASKS table using the contents of the VSAM task list. When the recovery is complete, message DSNA695I displays on the console to indicate that both task lists are again available. (By default, message DSNA679I displays on the console once per minute. You can change the frequency of this message by modifying the ERRFREQ parameter. You can modify this parameter as part of the started task or with a console command.)

Procedure

To recover the task list if it is lost or damaged:

  • To recover if the ADMIN_TASKS task list is corrupted:
    1. Create a new and operable version of the table.
    2. Grant SELECT, UPDATE, INSERT and DELETE privileges on the table to the administrative task scheduler started task user.
    As soon as the ADMIN_TASKS table is accessible again, the administrative task scheduler performs an autonomic recovery of the table using the content of the VSAM task list.
  • To recover if the VSAM file is corrupted, create an empty version of the VSAM task list.
    As soon as the VSAM task list is accessible again, the administrative task scheduler performs an autonomic recovery using the content of the ADMIN_TASKS task list.
  • If both task lists (the VSAM data set and the ADMIN_TASKS table) are corrupted and inaccessible, the administrative task scheduler is no longer operable. Messages DSNA681I and DSNA683I display on the console and the administrative task scheduler terminates. To recover from this situation:
    1. Create an empty version of the VSAM task list.
    2. Recover the table space DSNADMDB.DSNADMTS, where the ADMIN_TASKS table is located.
    3. Restart the administrative task scheduler.
    As soon as both task lists are accessible again, the administrative task scheduler performs an autonomic recovery of the VSAM task list using the content of the recovered ADMIN_TASKS table.