Information Technology Reference
In-Depth Information
10.
If the host is a member of a cluster, you can choose whether to disable any of the cluster
settings for DPM, HA, and FT, if you think they may interfere with the remediation pro-
cess. VUM version 5 now has the option to remediate several hosts at once if the cluster
has sufi cient compute resources to meet the other cluster controls. In Figure 4.29 you can
see the full gamut of cluster options.
Figure 4.29
Cluster options
during host
remediation
11.
Review the summary screen, and click Finish if everything is correct. If there are any
errors, use the Back button to double-check and change the settings.
If you selected to have the remediation occur immediately, which is the default setting, VUM
initiates a task request with vCenter Server. You'll see this task, as well as some related tasks, in
the Tasks pane at the bottom of the vSphere Client.
If necessary, VUM automatically puts the ESX/ESXi host into maintenance mode. If the host
is a member of a DRS-enabled cluster, putting the host into maintenance mode will, in turn, ini-
tiate a series of vMotion operations to migrate all VMs to other hosts in the cluster. It's common
to see the remediation task pause for an extended time at the 22% point. This is normal and it
often takes around 15 minutes to complete the migrations before progressing further. After the
patching is complete, VUM automatically reboots the host, if it is required, and then takes the
host out of maintenance mode.
Keeping Hosts Patched Is Important
Keeping your ESX/ESXi hosts patched is important. We all know this, but too often VMware admin-
istrators forget to incorporate this key task into their operations.
VUM makes keeping your hosts patched much easier, but you still need to actually do it! Be sure
to take the time to establish a regular schedule for applying host updates and take advantage of
VUM's integration with vMotion, vCenter Server, and VMware Distributed Resource Scheduler
(DRS) to avoid downtime for your end users during the patching process.
