Invalid IP configured in Enterasys VH-2402S

[Dale]

I have acquired an Enterasys VH-2402S switch. I am unable to communicate with it using console management port via puTTy (black screen/no response) or any other method. I had no idea of the IP configured in this switch. After some thought, since I acquired this switch from a network guy, who also did not know the IP, suggested I try a range of IPs in the 172.22.xx.xx range since it came from his company. Using AdvanceIP Scanner I was able to determine the configured IP address of the switch is 172.22.xx.255. Wow. This is an invalid IP I'm sure, and is preventing me access to it via CLI / ethernet cable. How do I gain access to this switch? I asked that network guy and just got a shrug and statement that I probably can't. It's almost like he knew it and wasn't bothering with it... Anyway, any ideas on how I can get access to this switch to change the IP to make the switch useful? Thnks!

[Robert_Cummins]

Are you connected directly to this switch? I agree that it appears the switch is @ 172.22.35.255. Unfortunately, you have likely set this up to be routed and not switched and this is why.
The switch has a netmask of /23 right? You believe it is 172.22.35.255/23; that makes the network 172.22.34.0 and the broadcast address 172.22.35.255. When the switch replies to your packets it needs to send them to 172.22.32.15, which is not in its IP network so it will send the packet to the router. Now, if the router manages the IP network that contains 172.22.32.15, it will forward the packet to the appropriate VLAN for delivery to your system, if it doesn't then it sends it on to another router based on its routing rules.
To have a chance here you need to:

• plug into the switch directly
• configure an IP address on the same IP network as the switch (we think it is 172.22.34.0/23; it could be 172.22.35.0/24). The best address to use is 172.22.35.254/21 - why? B/c this address will be on all networks as 172.22.35.255 sans 172.22.35.255/32 and it is the first network (172.22.32.0/21) where the address 172.22.35.255 is not the broadcast address for the network.

It's important here that the two devices be on the same VLAN and in the same IP network. In your setup above the switch is on the same IP network as your system *as viewed from your system* but your system is not on the same IP network *as viewed from the switch*

Make sense?

[Dale]

I need to digest this... It seems I may not be plugging in the right stuff. I'll keep plugging away. Thanks!

Oh, also to answer you specific question. I am currently plugged into the switch via serial and ethernet PC to Switch.

[Dale]

I think I have now confirmed the switch IP Address as .255. Attached is nmap result and the way I configured the network adapter. With this result I tried an ethernet cable from PC to switch but it doesn't come up. Not sure where to go from here...

[Robert_Cummins]

Did nmap find anything @ 172.22.34.13? If not, then that's not the address of the switch or the switch isn't supporting common access protocols like telnet, ssh, or http. You might also try https (443), though at this point you might want to find a way to reset the switch to some kind of factory default.

[Dale]

No nmap didn't find .13. Based on my previous info about this switch, I really do believe this thing is set at .255