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Old Network admin left and deleted all previous info

I need a way of finding the IP for my switches, I also need to find a way to break into them without losing the config on them. Honestly this is probably a bit over my head as most of my training with cisco switches was back in 2003. I need to monitor traffic on my switches so I can find a bad NIC that is spewing packets that is causing my switches to cycle on and off for a split second. On top of that I would like to make backups of the config of all my switches and routers. Anyone have any advice that they can offer on how I can do this without bringing down my network and having to reconfigure my MPLS connection that I have.

I have a few Cisco 3750-X that do a little bit of routing. I can connect to my switch via the console cable, and access it with hyper terminal, but I am not at all familiar with most of the command lines I need or how to check port by port just using that. I really miss having access to a GUI.

  • LAN Switching and Routing
Hall of Fame Super Silver

Old Network admin left and deleted all previous info

If you can get an enable level access ("#" prompt) from the console, you can pull backups there.

If the previous admin setup the console port to require authentication, you will have to do a password recovery exercise to login and switch to enable mode. The procedure is documented here.

Once you have logged in (console), you can create a new username for yourself with a password you know. to get the IP address(es) of the switch, type "show ip int br | ex una" (= show ip interfaces briefly except those that are unassigned (aka unconfigured)).

You can then login using one of the configured addresses on the switch via ssh (or telnet = insecure). Login, go to enable level, type "term len 0", start your terminal session logging and type "show run". You now have a complete backup of your configuration.

If you want to see what errors the switch is seeing in general, type "show log". If the log is very short, if may be set to the default (4096 bytes). To change that, go into configure mode (conf t) and type "logging buffered 100000". "end" to exit configure mode and then save ("copy run start").

There is a GUI on the 3750X. You may need to enable it ("ip http server" or "ip http secure-server" plus "ip http auth local" from configure mode). The GUI lets you look at some basic settings from a browser.