Persistency

Persistency is a source-side subscription attribute that can be enabled or disabled. You must enable this attribute for those subscriptions you want to have automatically restarted after a normal or abnormal termination. To change the persistency attribute for a subscription, refer to the documentation in Management Console.

Continuous mirroring for a persistent subscription can automatically restart in response to a normal or abnormal termination of the following:

  • InfoSphere® CDC address space

    For persistent subscriptions that were active when the termination occurred, continuous mirroring automatically restarts when the address space reinitializes.

    However, persistent subscriptions that were terminated or became inactive as a result of a direct request are not restarted automatically during address space initialization.

  • DBMS

    For persistent subscriptions that were active when the termination occurred, continuous mirroring automatically restarts when the DBMS reinitializes.

  • Communications

    For persistent subscriptions that were active when the termination occurred, continuous mirroring automatically restarts when communications are reestablished.

  • Target server

    For persistent subscriptions that were active when the termination occurred, continuous mirroring automatically restarts when the subscription server is restarted.

When communications or the subscription server terminates, InfoSphere CDC attempts to automatically restart continuous mirroring for persistent subscriptions at regular intervals. Attempts continue until an automatic restart is successful or the persistent subscription or InfoSphere CDC address space is terminated. You can set how often InfoSphere CDC attempts to automatically restart continuous mirroring for all persistent subscriptions by modifying the AUTORESTARTINTERVAL configuration control statement keyword.

Persistency is only relevant to subscriptions that are used for continuous mirroring. If a persistent subscription is used for refresh, the subscription will not be restarted. If a persistent subscription is used for net change mirroring and ends as specified, the subscription will not be restarted.

For nonpersistent subscriptions, you must manually restart continuous mirroring after normal or abnormal termination.

Note: Existing processes using CHCMTAUT for configuration should be migrated to Management Console since this command will be discontinued in a future release.