Discover IPMI IP address by scanning all possible direct LAN addresses

Question

I have a Supermicro server board that powers on but wont post.

I have connected a LAN cable to the dedicated IPMI LAN port on the board and am trying to discover what the IPMI IP address of the board is.

I have tried scanning the local network via:

nmap -n -sP 192.168.1.1/24

However I as the server is not connected to anything other than a laptop via IPMI it does not know it's on the local network, and I have seen SuperMicro IPMI addresses around 172.17.x.x.

I have not been able to find a list of all possible IPMI addresses to narrow down. How can I scan the entire 172.x.x.x address range using nmap? or any other ideas for finding this server via direct connection to an IPMI port.

I don't understand what you're saying. Is the server IPMI port connected to the network or not? — joeqwerty, May 31 '20 at 02:39
IPMI port is connected to a laptop. I am running nmap on the laptop to find the server. — proximacentauri, May 31 '20 at 02:46
Give your laptop an ip address in the range you want to scan, then scan it. — joeqwerty, May 31 '20 at 02:49
No luck scanning the 172.16.x.x network after setting laptop address. May be the board isn't posting an IPMI address — proximacentauri, May 31 '20 at 03:46
What subnet mask did you give your laptop? Why do you need IPMI? If the server won't post chances are it's dead — jstuart-tech, May 31 '20 at 05:01
I set my laptop to ipv4 172.16.12.xx, Netmask 12, Gateway (not really sure) 172.16.0.0. Added details of wireshark trace to post — proximacentauri, May 31 '20 at 07:36

score 1 · Answer 1 · answered May 31 '20 at 09:49

I connected a laptop directly to the IPMI port on the server baord, then I used wireshark on the laptop to find the IPMI address (ARP broadcast by MS_NLB Phys Server) (NB turning off wifi first to quieten the logs). Then I set the lap to use the same Class B 172.16.12.xx based network as @joeqwerty helpfully pointed out by editing netplan config (eg see https://danielmiessler.com/study/manually-set-ip-linux/).

Then I could ping the IPMI address from the laptop and browse to the login screen at https://172.16.12.xx

interesting, is there a way to find that without requiring physical access? — xeruf, Jan 18 '23 at 10:16

Discover IPMI IP address by scanning all possible direct LAN addresses

1 Answers1