I have the same issue, I have received a decommissioned SR2024 for my enthusiast homelab, I can SSH into the switch but web ui gives me a 503 error. I am not sure if im just out of luck. What command would I use to provide you the firmware version?
Id love to integrate this SR2024 in my homelab, I like to use old enterprise gear to give them a new purpose.
EDIT: running show version results in this:
Version: HiveOS 6.5r4 Honolulu build-128121
Build time: Wed May 4 07:13:28 UTC 2016
Build cookie: 1605040013-128121
Bootloader ver: v0.0.2.36
TPM ver: v126.96.36.199