Automate vCenter 8 upgrade starting at stage2

[Mkwoolery]

I'm looking for a way to initiate the upgrade sequence starting at stage2.  We need to add a static route to the VCSA before it can see infrastructure (like DNS, the hosting vCenter, etc). The only way i can think of doing this is either trying to insert this route into the /etc/systemd/network/10-eth file while the VCSA is initiating, or by deploying the OVA as a separate task.  AFAIK, the cli-installer has no mechanism to add an additional route or a way to 'pause' the install before it automatically goes to stage2.

  If i deploy the OVA first, i can log into VAMI and i get the same screen as if i had ran the ui-installer.  But is there a way to initiate the upgrade sequence at this point?

Has anyone had to do anything similar? The process is fairly easy - if i'm using the UI installer, there is a natural pause once the VCSA is stood up and waiting for me to go through the upgrade wizard.  The route can easily be added at that time.  I'm trying to avoid having to manually upgrade 100+ vCenters.  

 

 

 

 

[Aritra De]

You may want to explore the templates in the CLI method: https://blogs.vmware.com/vsphere/2018/09/upgrading-platform-services-controller-and-vcenter-server-via-the-cli-installer.html

[Mkwoolery]

Yep, that is what i was referring to, but the problem is that there is no way that i'm aware of to add a route to the json file, so the only way this would work is if somehow i'm able to reliably time it so i can modify the route via powercli or an ssh script before the stage1 is complete.  If i just let the cli method run, in our environment, it will just error out because it cannot get to the hosting vCenter to make the cutover.  

Our networks are something like this:

vcenter ip: 10.0.0.10

gw 10.0.0.1 (this is out to the internet via a firewall)

Route 10.0.0.254 destination 192.168.0.0/14 (for internal traffic - the hosting vcenter, DNS, ldap, backups, etc)