About the Reuse VM selection query results option
This topic applies to NetBackup for VMware.
The NetBackup Test Query screen lists the virtual machines that NetBackup discovered in your virtual environment. Because the automatic selection feature is dynamic, later changes in the environment may affect which virtual machines match the query rules. For example: if virtual machines are added later, the current test results may not be identical to the virtual machines that are selected when the backup runs.
During the period you specify on Reuse VM selection query results for, NetBackup reuses the current list of virtual machines as the backup list. It does not consult the Query Builder or rediscover virtual machines.
The less often your virtual machine environment undergoes changes, the more advantageous it may be to reuse the list of virtual machines for backups. In large environments, discovery of virtual machines takes time and consumes resources on the vCenter server.
Note the following about the Reuse VM selection query results option:
Determines how long the query results are reused (that is, how often the list of discovered virtual machines is refreshed).
Controls how often NetBackup performs discovery on the vCenter server.
For the environments that contain many virtual machines, the discovery process may increase the load on the vCenter server.
Has no effect on the NetBackup policy execution schedule.
Is invalidated if the query rules are changed or if the policy attributes that affect discovery are changed. In that case, NetBackup rediscovers virtual machines the next time the policy runs.
The following topic describes the policy attributes that affect discovery:
See Effect of Primary VM identifier parameter on Selection column in Test Query results.
For example: assume that the option is set to 8 hours and your query selects turned-on virtual machines. If additional virtual machines are turned on during the 8-hour period, they are not added to the policy's backup list. The policy backs up the virtual machines that were last added to the list (such as when the policy was created). After 8 hours, at the next execution of the policy, the recently turned on virtual machines are discovered and added to the backup list.
If the next backup occurs before the Reuse period expires, and a virtual machine was renamed during the Reuse period, NetBackup backs up the renamed virtual machine under its original name. Because the reuse period has not expired, NetBackup does not rediscover virtual machines and therefore cannot identify the virtual machine by its new name. (NetBackup identifies the virtual machine by its instance UUID.) To have backed up the virtual machine with its new name, the Reuse period should have been set to a shorter interval.
Note: The virtual machines that have been selected for backup are not displayed on the policy Clients tab. To see which virtual machines NetBackup has selected and backed up, refer to the following topics.
See The effect of virtual machine discovery on vCenter.
See Using the Activity Monitor to monitor virtual machine backups.