AUTOBACKUPSTART: Specifying when automatic backup is to start

Explanation: AUTOBACKUPSTART((hhmm1 hhmm2 hhmm3) is an optional parameter specifying the time when automatic backup can start. The first time you specify (hhmm1) is the time you plan for DFSMShsm to start automatic backup. The second time you specify (hhmm2) is the latest time DFSMShsm can start automatic backup. The third time you specify (hhmm3) is the time after which DFSMShsm will not start automatic backup on additional volumes.

If DFSMShsm does not start automatic backup between the planned start time and the latest start time, no automatic backup is run that day.

For hhmm1, substitute the planned time for DFSMShsm to start automatic backup. If you specify hhmm1 as zero, DFSMShsm cannot start automatic backup.

Note: Time is based on the 24-hour clock and is expressed as a four-digit decimal number in the format hhmm. The hour is represented by hh and the minutes by mm. For example, 1:15 p.m. is 1315 and midnight is 2400. The maximum value you can specify for hh is 24, the maximum value you can specify for mm is 59, and the maximum value you can specify for hhmm is 2400.

For hhmm2, substitute the latest time DFSMShsm can start automatic backup. If hhmm2 is set to zero, this is the same as not including the hhmm2 parameter and DFSMShsm runs automatic backup processing until all volumes have been backed up. If you want automatic backup to begin after midnight, the value for the latest start time can be smaller than the planned start time. For example, you can specify 2330 for hhmm1 and 0100 for hhmm2.

For hhmm3, substitute the time after which DFSMShsm can no longer start automatic backup of additional volumes. If hhmm3 is set to zero, this is the same as not including the hhmm3 parameter. If you do not specify hhmm3, DFSMShsm runs automatic backup processing until all volumes have been backed up.

If you want automatic backup to begin after midnight, hhmm2, the latest start time, can be smaller than hhmm1, the planned start time. As an example, you can specify 2330 for hhmm1, 0100 for hhmm2, and 0330 for hhmm3. DFSMShsm assumes that hhmm2 is a later time than hhmm1 and hhmm3 is a later time than hhmm2.

SMS relationship: Parameter has the same meaning when applied to SMS-managed or non-SMS-managed DASD volumes or data sets.

SETSYS default: If you do not specify a value for hhmm2, the SETSYS default is 2400.

DFSMShsm default: If you do not specify this parameter on any SETSYS command, the DFSMShsm default is no automatic backup.
Note:
  1. If you do not specify a nonzero value for hhmm1 during this start up of DFSMShsm, DFSMShsm does not do automatic backup.
  2. The maximum value you can specify for mm is 59, and the maximum value you can specify for hhmm1, hhmm2, or hhmm3 is 2400.
  3. You use the BACKUP parameter of the DEFINE command to specify on which days DFSMShsm is to run automatic backup. The AUTOBACKUPSTART parameter specifies the time when automatic backup can start. If automatic backup does not start before the latest start time, DFSMShsm does not start automatic backup until the next day in the cycle that automatic backup is scheduled to run. If automatic backup did not start today, you can use AUTOBACKUPSTART to change the planned and latest start times.
  4. DFSMShsm serializes access to your data sets and volumes for a short period of time while it runs automatic backup. Therefore, choose a time for automatic backup when the computing system is not very active and there is not much interactive user activity.
  5. If you want the operator to decide whether DFSMShsm should start automatic backup, specify the REQUEST parameter and the AUTOBACKUPSTART parameter.
  6. If you specify hhmm3 as zero, automatic backup will process all eligible primary volumes.
  7. The SETSYS command fails if hhmm1 and hhmm2 are equal or if hhmm2 and hhmm3 are equal.
  8. DFSMShsm does not honor the value for hhmm3 until the volume phase of the AUTOBACKUP function.