If you have SSH access to your ESX server, smbiosDump has some very useful information. If you look in “OEM Strings: #14”, you can see some very useful information:
[root@ucs-test1:~] smbiosDump | grep “OEM Strings: #14” -A 4
OEM Strings: #14
$SPI:rack-unit-13 <- Server ID
$SPT:hx-nodes <- Service Profile Template
$SYS:test-fi1 <- Fabric Interconnect
This info can be nicely scripted so you can find what host is associated with which FI, or what server ID (rack-unit) shows via UCSM.