Last article I configured Update manager (VM) and imported esxi ISO image. I will be updating my existing ESXi 5.5 to Esxi 6.0 using it. In the vSphere client, Select Esxi server need to be updated, This is running Esxi 5.5 as underlined, go to Update Manager tab in the right, and click attach to add esxi server upgrade baseline. (This procedure can be done on complete vcenter, virtual datacenter or cluster). Once baseline is attached scan it to check compliance.
PART 3.1 : VMWARE VSPHERE UPDATE MANAGER INSTALLATION ON WINDOWS 2012 R2
PART 3.2 : VMWARE VSPHERE UPDATE MANAGER PLUG-IN INSTALLATION ON VSPHERE CLIENT
VMWARE VSPHERE UPDATE MANAGER (VUM) - IMPORTING ESXI ISO AND CREATE UPGRADE BASELINE
VMWARE VSPHERE UPDATE MANAGER (VUM) - UPGRADE ESXI OS
Here is the list appear of all baselines and groups. I have selected Host upgrade baseline, I created earlier manually containing ESXi ISO.
I scanned to check compliance and it shows red box with cross mark means it is non-complaint. Click on Remediate to start downloading updates on the Esxi server and upgrade it at a time. (Stage will only download updates on ESXi server, it will be faster when you remediate at scheduled time)
This is Remediation selection page, I have only one baseline and will click next
Check I accept box for EULA., Next screen is warning about unsupported drivers after upgrading from Esxi 5.5 to Esxi 6.0, and someof the hardware may not work due to driver incompatibility and ESXi or some functions may not work this is also applies for VMFS Datastore compatibility as well, I am keeping it default
Remediation (Esxi upgradation) can be scheduled through VUM update manage I requires Task Name, Schedule time can be selected in off hours, I am updating host immediately. 
This settings is Before host remediation, Esx/Esxi hosts might need to enter maintenance mode. VMs must be shut down or migrated, If you are using clusters VMs will be automatically vMotioned and Esxi server is put into Maintenance mode. There are retry delay and Number of retries options incase it fails to go into maintenance mode.
This is summary page and ready to complete, review the configuration and press Finish. In the background I can see, Update Manager VUM has put server into maintenance mode, Esxi server is restarted and OS upgrade is started, corresponding task can be viewed.
If everything is fine Server will boot up and new OS details can be views on ESXi summary tab and in the Update Manager tab Esxi is showing Green compliant on attached Baseline.
