epoch_watchdog

Checks whether a replica's epoch numbers have rolled back when the replica is not in restoration mode

Applicability

Product Command Type
MultiSite MultiSite command
Platform
UNIX®
Linux
Windows®

Synopsis

  • Check for rollback of epoch numbers:
    epoch_watchdog
    { –all | –vobs VOB-tag,... | list-file }
  • Print help on command options:
    epoch_watchdog
    –help

On Linux® and the UNIX® system, epoch_watchdog is located in versionvault-home-dir/config/scheduler/tasks. On Windows®, epoch_watchdog is located in versionvault-home-dir\config\scheduler\tasks.

Description

epoch_watchdog checks whether a replica's epoch numbers have rolled back without a restorereplica command being run. If the epoch numbers have rolled back and the replica is not in restoration mode, the replica may have been improperly restored from backup. This script is intended to be run regularly by the VersionVault scheduler. For more information, see the schedule reference page in the Help.

epoch_watchdog writes a replica's epoch number to a log file in /var/adm/hcl/versionvault/log/epoch_logs on Linux® and the UNIX® system or versionvault-home-dir\var\log\epoch_logs on Windows®. The next time the script is run, it compares the current epoch number to the logged number. If the current number is lower than the logged number, epoch_watchdog checks to see if the replica is in restoration mode. If the replica is not being restored, epoch_watchdog attempts to lock the affected VOB, and optionally sends e-mail notification. You must specify e-mail addresses in the scheduled job. In this situation, you must contact HCL Customer Support before unlocking the VOB or attempting any repair procedures.

Note: If you do not schedule epoch_watchdog to run frequently, the activity level in the replica can be high enough that a rollback may not be detected if restorereplica is not performed.

If an error occurs, epoch_watchdog creates an entry in /var/adm/hcl/versionvault/log/error_log on Linux® and the UNIX® system or the Event Viewer on Windows®. This entry references the epoch_logs file.

Restrictions

You must be root on Linux® and the UNIX® system or a member of the VersionVault administrators group on Windows®.

Options and arguments

–h/elp
Prints help on command options.
–all
Checks all replicated VOBs on the current computer.
–vobs VOB-tag,...
VOB tags of replicated VOBs to be checked. Specify multiple VOB tags in a comma-separated list with no white space.
list-file
Path to file containing a list of VOBs to check. Specify one VOB on each line, with no white space, in the form vob:VOB-tag

Examples

For an example of the command, see "Running epoch_watchdog" in the Help.

Files

/var/adm/hcl/versionvault/log/epoch_logs (Linux® and the UNIX® system)

/var/adm/hcl/versionvault/log/error_log (Linux® and the UNIX® system)

versionvault-home-dir\var\log\epoch_logs (Windows®)