Anupreet01 wrote:
I have 7 Hosts how to upgrade from 4.1 to 5.1
There is a "right" way to do it, as officially supported by VM ware, and then there is the user way to do it, that's been tested and verified.
The "right" way is to upgrade either by CD, ISO or upgrade patch.
The user community will tell you to:
1) put host in maintenance mode
2) migrate ALL VM's off of host (don't forget those templates!)
3) ensure ALL required data is moved from host
4) use the DVD / CD / ISO to boot the host.
5) install host as NEW (format, don't need to delete datastore but if you don't you won't be able to benefit from new VMFS 5.0 file system)
rename the host, add to vCenter, etc.. it's MUCH better to install as new than to upgrade, this is from EXPERIENCE as well..
Starting fresh for a new host is preferable, it only takes 10 minutes to install and if you have host profiles in vCenter you can make configuring the host a breeze after that...
VM ware wants to encourage you to upgrade so they can make things easier, but upgrades sometimes misses stuff, great if you don't have a choice. I always do FRESH installs of major upgrades myself...