We have upgraded OS 2008 to 2012 Win for 12K devices.
VMware will not provide advice on upgrading underlying OS version. This is MS product and not theirs. They will say no. I have been through that.
In place Windows upgrade is a hit and miss. Not reliable doing this on a production environment. Tried that. It would be nice if it did work it would save all the networking changes.
Best approach is:
1. Build all new 2019 servers and all the WS1 pre-reqs installed and configured for all your CS, DS and DB. Give them new server names and Temp IP address. This includes your certs, Java, IIS, .NET, etc etc.
2. Get a copy of the DB onto the new DB sever
3. Install CS and DS and point them to the copy DB on the new DB sever. That is to ensure that the CS, DS and DB servers can all link up nicely. You won't be able to manage any devices as it is not hooked onto your external DS address.
4. Plan for any network changes such as NLB, IP address.
5. Make sure IIS on DS and CS is turned off and disabled and or DS and CS removed from NLB. Shutdown all CS and DS. Move the DB to the new DB sever. Make sure DB name is the same as the copy DB already existing on the new DB server. Shut old DB server down. Swap DB servers IP. Start up new CS, swap IP with old CS. Enable and Start IIS on CS. Ensure you can open the console and and login. Do the same for DS. And finally re-add DS and CS to any NLB that you have removed them from. They should all come up.
6.Don't forget to update your DNS entries with your new 2019 server names and IP addresses.
NB: For DB migration from OLD to NEW server, there is a doc from VMware. You will need your DBA and WINTEL guys to help.
That is a brief outline of your upgrade process but you need to plan carefully every detail to ensure your are not leaving anything out. Also perform each of the steps in the correct order.
Good luck.
