Retry count and restart interval

• Retry count. The retry count specifies how many times PowerHA® SystemMirror® should try restarting before considering the application failed and taking subsequent fallover or notify action.
• Restart interval. The restart interval dictates the number of seconds that the restarted application must remain stable before the retry count is reset to zero, thus completing the monitor activity until the next failure occurs.

If the application successfully starts up before the retry count is exhausted, the restart interval comes into play. By resetting the restart count, it prevents unnecessary fallover action that could occur when applications fail several times over an extended time period. For example, a monitored application with a restart count set to three (the default) could fail to restart twice, and then successfully start and run cleanly for a week before failing again. This third failure should be counted as a new failure with three new restart attempts before invoking the fallover policy. The restart interval, set properly, would ensure the correct behavior: it would have reset the count to zero when the application was successfully started and found in a stable state after the earlier failure.

Be careful not to set the restart interval for a too short period of time. If the time period is too short, the count could be reset to zero too soon, before the immediate next failure, and the fallover or notify activity will never occur.