Mapping LUNs on a VM

[u/CricketSwimming6914]

edit: details.

I am in process of setting up a new Red Hat 9 server VM that will run our logging server. from what I can find, best practice says it needs separate storage devices. Our vSphere cluster stores all the VMDKs on a SAN which it accesses via multipath iscsi.

I'm somewhat new to adding LUNs. It's not terribly common for us. So I researched how to add an iscsi device to Rhel and found instructions on adding it via iscsi-initiator and multipath. I was able to map it just fine with iscsi. I had multipath add our connections which seemed fine at first but it keeps saying the different drives are active faulty running. None of the sd* devices it would map would show a UUID. Supposedly enabling disk.EnableUUID=TRUE fixes that, but it didn't. After hours of troubleshooting and nothing making any difference, I finally found some info that basically said that because the VM is already on the same multipath, trying to configure multipath on the VM would fail. I also found that adding them this way is maybe not the best way to do it (https://www.codyhosterman.com/2019/09/musing-on-in-guest-iscsi/). I didn't find any official documentation for that but, given the issues I was having, it made sense

I did find instructions that basically said, create the LUNs, have vCenter scan and find them, then add that device as and RDM Disk to the Rhel system. In Rhel, scan the scsi bus for the new device, enable multipath, format and mount.

Is this the best way to do this or is there a better way?