Where would I find the info required to activate the Supermicro IPMI license in order to check for BMC updates etc?
You have to pay for that license. See this other thread
Firmware updates for the BMC are available from supermicro.com and you can just install those without activating any licenses – start your search over here for these:
What you get with the OOB License is an easier way to do BIOS updates, but again, you can download those from supermicro.com and do it in more manual ways without paying to activate the license. Something like netboot.xyz is invaluable for quickly booting a live environment for updates.
Some other aspects like emitting syslog messages don’t have a great workaround and that’s where you really are into paying $27, enduring the terrible store, and activating the license.
Great reply full of really useful information. Thanks!