As you know, there are many ways to upgrade or patch ESXi hosts within a VMware environment. If you just have a lab with one isolated host, this article won't be for you. But if vCenter Server manages your environment, and it has more than two or three hosts, you'll certainly be grateful to find this article explaining how to upgrade an ESXi host with vSphere Update Manager (VUM).

If you run just a single host, you can use the command-line interface (CLI) to upgrade it. However, with more hosts connected, the process might need more of your time where you manually put your host into maintenance mode each time, do the upgrade, exit the maintenance mode, and so on.

That's why VMware has VUM, which can take care of this automatically. Since vSphere 6.7 U2, VUM has had some changes in the right direction: ease of use.

I assume your ESXi hosts are on the VMware hardware compatibility list (HCL) and your backup software supports vSphere 6.7 U2. You should always check whether it is wise to upgrade your environment before actually starting the upgrade process itself.

System requirements

Latest VCSA: To use the latest innovations from VMware, you must be running the latest vCenter Server Appliance (VCSA) 6.7 U2.

This is not a problem because VMware has greatly simplified the upgrade for VCSA, and you can do it via the vCenter Server Appliance Management Interface (VAMI) without any Linux knowledge. You may want to check out our article Three ways to update VMware VCSA.

Steps to upgrade the ESXi host

First, we want to check the version number we're on. By selecting an individual host, you can see it on the Summary tab.

Upgrade vSphere ESXi to 6.7 U2

Upgrade vSphere ESXi to 6.7 U2

Connect to your environment via vSphere Web Client and select the host or cluster you wish to upgrade. VMware allows you to select the cluster entity to automate the upgrade process. If you select a cluster, VUM will evacuate the first host via vMotion and put this host into a maintenance mode prior to starting the upgrade process.

Once the upgrade succeeds and the host reboots, VUM will automatically take the host out of maintenance mode and vMotion the VMs back. This process continues automatically like this with all the hosts present in the cluster.

But let's assume you only want to upgrade a single host. In this case simply select only a single host, go to Updates, select Host Updates, and Attach Baseline or Baseline Group.

Select a single host to upgrade via VUM

Select a single host to upgrade via VUM

This will bring up a new window asking you which baselines you want to attach. By default, VMware has two baselines. Select the check box next to the Name column to select both predefined baselines.

You cannot edit or delete predefined baselines; you can only attach or detach them to the respective inventory objects.

Attaching a baseline or baseline group to a single host

Attaching a baseline or baseline group to a single host

With the two baselines selected, hit the Remediate button.

Select both predefined baselines

Select both predefined baselines

Once you hit the Remediate button, you'll see a window like the one below where a pre-check will inform you whether any major issues would prevent the successful upgrade.

It could be an unsupported NIC driver or storage RAID card that might lack support in the latest version.

You can also see that there will be 43 updates installed, and if you click the details, you can see whether a reboot will be required and for which patch. You will also be able to see whether it will install a patch, rollup, or upgrade.

Click the Remediate button

Click the Remediate button

Click the Remediate button again to start the process. You can check the tasks and monitor the progress. Once the host remediates, the process automatically reboots the host.

Check the upgrade progress

Check the upgrade progress

Once the upgrade and patches install, the host reboots. We can check the version and see we have upgraded our host with success.

Upgrade completed with success

Final words

The upgrade process via VUM is getting better in every release. VUM is now fully integrated into VCSA, and you can use the HTML5 web client as well. This wasn't always the case. Previous releases of vSphere had to use the Flash web client, which was slow and buggy. Users with vCenter Server on Windows had to install VUM as a separate component.

But now, most users have migrated or are still migrating the Windows-based vCenter to VCSA (VMware has developed a nice workflow for this).

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The advantage of using VUM is that you don't have to sit and monitor the update process for each host of the cluster. VUM will take care of moving VMs to another host in the cluster while updating or patching the host. There are some requirements such as the fact that your cluster has to have vMotion enabled and you, of course, have to have vSphere with a vMotion license. You can find the lowest version of vSphere with a vMotion license in vSphere Essentials Plus.

  1. Avatar
    Manish Shukla 4 years ago

    Do  we need to unmount shared storage from ESX host prior to upgrade node in cluster?

  2. Avatar
    Eric 3 years ago


    What if your vcenter appliance is installed on the host you want to patch?

    Still connect to the host via vSphere web client and follow the normal steps?


    Thank you,



    • Avatar Author

      Hi Eric,

      If your VCSA is running on the host you want to patch, you have 2 solutions:

      1. You vMotion the VCSA to another host
      2. You don’t have vMotion license so you have to patch the host manually (via CLI).

      • Avatar
        Eric 3 years ago

        Thank Vladan,

        Not having vMotion could I also migrate the VCSA  from one host to another?


        • Avatar Author

          Well, assuming you certainly have some kind of shared storage where VCSA "lives", you could possibly shut down VCSA > register the VCSA on another host (by browsing the datastore from the host web console, and double-clicking the *.vmx file). Then start the VCSA and do the upgrade of the initial host. I hope that makes sense.

          • Avatar
            Eric 3 years ago

            Yes makes sense. Also was considering using Veeam B&R to do a quick migration.

            Shutting down the VCSA is not an issue as related to down time. 

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