I have a NetVanta 1234 that seems to be operating, but I cannot access any management features. I have tried the Web GUI, telnet, and direct serial connection.
I will reboot if necessary, but that will take down half my network so I am trying to avoid it.1234config
You didn't mention if you tried ssh. It sounds like all of the services are turned off for some reason. I've never seen the serial console not respond unless the unit is faulty. Obviously, a healthy reboot is the first step. I would connect to the serial console port and have my putty/console app running so you can see if something is wrong during the reboot.
Does it respond to pings? If you have it connected to another Adtran switch you can go to the LLDP section and see if it see it in there. I agree with vmaxdawg and just reboot it after hours with a console cable hooked up. Once it's back up maybe check the firmware level and see if your running something really old. Though I've got a site where many of the switches have been up for almost 3 years without a problem, I have seen other equipment that sometimes just needs to be power cycled regularly due too firmware bugs.
FWIW I did have a 3448 that recently lost all ability to be managed. Even the console port just gave me garbage. When it rebooted it would not do the normal startup sequence with the LED's flashing it would just all go green and pass traffic on the switch side but never on the WAN side. Could be something similar where the firmware has gotten corrupted/fried.
Reboot has not changed the results. I do see the unit in LLDP and can ping it. Here is something strange, I noticed the name of the switch has changed and is now the same as another switch. This should be #####_1234_B and is showing up as #####_1234_C.
Sounds like you may have the same IP address on both switches. Try changing the IP on which ever one you can get to and check your pings and login again. I had this happen to a customer site when they copied the config out of one switch and put it on their spare switch when they needed to use it.
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