VMware vSphere Update Manager 6.5 is now embedded into the vCenter Server Appliance (VCSA). If you have more ESXi hosts to upgrade patch or version upgrade, VMware suggest that choose VMware Update Manager (VUM) for upgrading hosts. The following demonstration, I will upgrade one vSphere 6.0 to 6.5 via VMware Update Manager 6.5.
NOTE: You need to move all working virtual machines to the standby vSphere hosts by vMotion when you apply any ESXi patch or version upgrade, then you start to upgrade task.
Firstly go to the Update Manager in the home page.
Go to ESXi Images tab, then clicks “Import ESXi Image” button to import 6.5 Image into Update Manager.
Then Create baseline.
Input the Upgrade Baseline Name, eg vShpere 6.5.
Click compliance view button after you created the baseline.
Clicks Attach Baseline button.
Select vSphere 6.5 Upgrade Baseline and OK.
Then clicks Remediate button.
Select the upgrade baseline, then Next.
Select which host needs to upgrade version 6.5, then Next.
And the option where you can save as the default host remediation options for future use.
After clicks Finish button, it executes to host upgrade.
The host will enter to maintenance mode automatically then starts to host upgrade.
NOTE: It exits the maintenance mode automatically after the upgrade is successfully completed.