Upgrade to vSphere ESXi 6 via command line

The other day i had to upgrade my lab ESXi mgmt server from version 5.5 to 6.0 host via the command prompt and it’s actually pretty straight forward. I took the following steps to perform the upgrade:

1. Download the latest ESXi version from the VMware website
2. Log on to the ESXi server using SSH
3. Verify running ESXi version using e.g.
   1. run the following command:
      vmware -v
      In my case i was running ESXi 5.5.0 build-2143827
      
   2. Starting the Direct Console User Interface (DCUI) from the SSH session by typing:
      dcui
      
      Press ctrl c to leave the DCUI mode and get back to the original SSH session
4. Upload the ESXi .zip depot to the ESXi host by running the following command:
   scp VMware-ESXi-6.0.0-2494585-depot.zip root@10.10.100.xyz:/vmfs/volumes/54aeddbd-e5943701-1cf2-f8db88fbd420/
   
   The 54aeddbd-e5943701-1cf2-f8db88fbd420 directory is scratch directory where e.g. the core, downloads, var directories exists. When upgrading multiple ESXi hosts you should use a shared datastore but i didn’t have one available for my single ESXi mgmt host. Thanks Mostafa for pointing this out.
   
5. Shut down the running virtual machines on the host byt first identify their VM IDs and then shutting them down:
   1. Identify VM IDs by running:
      vim-cmd vmsvc/getallvms
      This will give you output like:
      Vmid/Name/File/Guest OS/Version/Annotation
      In my case e.g:
      12/ad01/[MGMT-DS02] ad01/ad01.vmx/windows8Server64Guest/vmx-10
   2. Shut down the VMs by running:
      vim-cmd vmsvc/power.shutdown 12
6. Put the ESXi host in maintenance mode by running the following command:
   vim-cmd /hostsvc/maintenance_mode_enter
   
7. Verify the existing ESXi host software profile by running the following command:
   esxcli software profile get
   In my case i was using the Standard profile
8.  Verify the profiles available in the VMware VMware-ESXi-6.0.0-2494585-depot.zip file by running the following command:
   esxcli software sources profile list –depot=/vmfs/volumes/54aeddbd-e5943701-1cf2-f8db88fbd420/VMware-ESXi-6.0.0-2494585-depot.zip
   Important: Make sure to use two minus – – signs before depot
   Both the Standard and no-tools profiles were included
9. Perform the upgrade by running the following command:
   esxcli software profile update –depot=/vmfs/volumes/54aeddbd-e5943701-1cf2-f8db88fbd420/VMware-ESXi-6.0.0-2494585-depot.zip –profile=ESXi-6.0.0-2494585-standard
   Important: Make sure you use
   * the update and not install command
   * use two minus – – signs before profile
   This was the output from the successful upgrade: 
10. Reboot the ESXi host, via DCUI
11. Log on via SSH when the host has been rebooted
12. Verify that the new version is running using “vmware -v”,  “dcui” or “esxcli software profile get”
    
13. Exit maintenance mode by running the following command:
    vim-cmd /hostsvc/maintenance_mode_exit
    
14. Power on your VMs by running the following command:
    vim-cmd vmsvc/power.on VMid
    In my case i started with the VM ID = 2

Simple as that to upgrade the ESXi host from version 5.5 to 6.0 via CLI.