How to upgrade ESXi 4.x,5,x and 6.x from Update Manager.

Today I am going to explain you have to upgrade ESXi with the help of vCenter update manger. 

1. Login to vCenter with required access
2. Click Home.
3. Click the Update Manager icon.
   
4. Under the Configuration tab, click Patch Download Schedule.
5. To view the Patch Download scheduled task:
6. Click Home.
7. Click Scheduled Tasks.
8. Click VMware vCenter Update Manager Update Download.
9. Click Home > Hosts and Clusters.
10. Highlight the ESX host you want to update and click the Update Manager tab.
11. Click Attach. Select Critical Host Patches and Non-Critical Host Patches baselines and click Attach.
    
12. Note: To create custom baselines click Home > Update Manager > Baselines and Groups > Create.
13. To scan the ESX host for missing patches against the repository, right-click on the ESX host and click Scan for Updates > Patches and Extensions > Scan.
14. Scan progress is shown by the Scan Entity task in the Recent Tasks.
15. The host scan does not affect running virtual machines.
16. If the scan fails, ensure that the ports between Update Manager and the ESX host are open. 
17. When the scan is complete you see the number of patches missing on the ESX host. If no patches are missing, you see Compliant.
18. To remediate the missing patches to the ESX host:
19. Power off all virtual machines or vMotion them to a different ESX host.
20. Place the ESX host into maintenance mode. Right-click on the ESX host, select Enter Maintenance Mode, and click Yes.
21. Right-click on the ESX host and select Remediate > Critical Host Patches and Non-Critical Host Patches baselines and click Next.
22. Select which updates or patches to install, click Next >Next > Finish.
23. Notes:
24. Remediate progress is shown by the Remediate Entity task in the Recent Tasks.
25. This task might take some time as Update Manager starts downloading patches from vmware.com.
26. If the remediation fails, ensure the ports between Upate Manager, the ESX host, and vmware.com are open.
27. The ESX host might reboot after remediation completes.