Install vSphere 6.5 with already formated VMFS datastores

[PatricNIX]

Hi!

I have a host with vSphere 5.1 and I need up upgrade to 6.5. This is a standard install and I need to upgrade to an HP custom install.

When I tried to upgrade I got a message saying it couldn't determine what version is was on so it would have to do a clean install.

My question is, are my datastores going to be formated if the drives are left in during the installation? Or can I just scan for new datastores when it's installed and it will find them as they where?

EDIT:

vSphere is insatlled on a USB drive so the system isn't installed on a drive used for datastore.

[linotelera]

Hi!

IMHO the safest way to upgrade is transitioning through 5.5 or 6.0...  indeed reading offcial doc: VMware vSphere 6.5 Documentation Library seems that min version is 5.5 : << To upgrade ESXi 5.5 hosts or ESXi 6.0 hosts to ESXi6.5, you can boot the ESXi installer from a CD, DVD, or USB flash drive.>>

[PatricNIX]

Maybe I was a little unclear in my question.

I'm going to do a clean installation och vSphere 6.5 HPE custom iso but I don't want to format the drives that are installed.

So will it format all the drives automatically when I install vSphere for the first time or will I be able to mount my datastores on the new istallation?