I just recently stood up vUM update 1 and was planning to bring our 5.0 hosts to 5.5 with it. Any arguments against doing this? I tend to go the clean install route since it makes me sleep better at night, but VMware recommends vUM being the first option, plus it will be nice to not have to rebuild my vSwitches again since I'm not licensed for Host Profiles. It's my understanding that vUM does not support any kind of clean install, correct? We are also a HP shop and we use HP custom images if that makes a difference. I read about many reasons to do a clean install from 4 to 5, but not much from 5 to 5.5. Any advice would be appreciated.
there is absolutely no issues with upgrading, I also run multiple HP shops and use the custom images one of my bigger clients running over 200 hosts and most of them have only been upgraded from ESX 3.0.2 to ESX 4.0 to ESX 4.1 to ESXi 5.0 to ESXi 5.1 and now running ESXi 5.5
Clean installs are not needed and make for more work, clean installs for me only happen with new hosts.
You are correct VUM can not do clean installs
VUM apply patches, and does not perform installations.
If the host is working properly and has no errors and is not stable in that case recommend a clean install.
I did an upgrade from 5.0 U2 to 5.5 U1 through VUM and it worked fine. I then decided to install clean for two reasons: 1. The upgrade appears to leave behind some old vibs. 2. The HBAs are detected differently in 5.5 and my vmhba numbers ended up being flipped.
When I add a new host to the cluster I prefer everything to be consistent. I am not sure you will get 100% consistency if some are upgrades and new hosts are fresh builds. I can say this is a pain if you have more than a few hosts. Perhaps someone can shed some light on the best way to make upgrades and clean installs consistent between releases. I may just be too picky.