I don't know about Illumos but setting up a Solaris 10 machine to provide block devices through multi path iSCSI was a breeze with all the tooling it had. No config files needed it was all command line.

It was for a university lab and it was the only ever contact I had with Solaris 10 and later versions or forks. I was mildly interested once since it had KVM but support was Intel only so that kept me away.

I remember some hypervisor and storage products based on Illumos like Nexenta and Soylent OS. I'm guessing those projects faded into obscurity.

Which is a shame. A lot of people was optimistic about OpenSolaris when it came out but Oracle gutted it.

Oracle ruined Sun Microsystems for sure, incl. OpenSolaris.

I finally got my hands on using a Solaris machine at my last job to upgrading the backup software.

All I could explain the OS as, was as a swamp. It's wants to work but doesn't work as it should and you always were knee-deep in sludge too.