Telnet into router

[TT0wnsend]

I have a 1700 series Cisco router that I was connected to a frame relay network. I no longer need that router and the frame relay services were cancelled. I now need to reconfigure the router for other services. Without the router being connected to my network, I need to telnet into the router using a PC or laptop and reconfigure the router. Using a rollover cable connected to the console port is not working. When I try to telnet, I need an IP address. How can telnet into the router without an IP address? Can I use a crossover cable from my PC to the console port?

[thisisshanky]

What software did you use to access the router - like Hyperterminal, SecureCRT, Teraterm, Procommplus etc ??? What settings did you use to access the router - Baud rate , Stop bits, Flow control etc ....Default Baud on all Cisco routers is 9600 (unless its changed)...

[TT0wnsend]

I went to a command line and used telnet command. The baud rate is set for 9600.VT100/Ansi emulation. I will try using a newer PC that I can use hyperterminal for and let you know the results of that. Thanks!

[Richard Burts]

As you said in the first post in this thread, to telnet requires an IP address and there is no IP address on the console port. So if you are connecting the serial port of the PC to the console port of the router you will not be doing telnet. You need some terminal emulation program such as HyperTerm, or TeraTerm, or SecureCRT, or something similar and will use it to establish a console session. Also you need to be sure that you have an appropriate cable to connect to the console.

HTH

Rick

[Kevin Dorrell]

Did this router ever have an IP address on an Ethernet, and is it possible it is still configured? If so, you could telnet through the Ethernet port.

What if it had an IP address but you don't know it? You might still be in luck, and CDP might still be enabled. If you connect it back-to-back with another Cisco router (to which you do have access, obviously) and you do a show cdp neighbor detail it might well reveal its IP address.

Kevin Dorrell

Luxembourg

[TT0wnsend]

Yes, when it was connected to our frame relay network (which is now replaced with VPN Watchguard firewall) it had an address of 10.3.4.1. If I want to connect it back-to-back with a router I have now (a Cisco 2600) what kind of cable should I use and which ports? Thanks so much for your help

[Richard Burts]

The most convenient and easy connection would be Ethernet port to Ethernet port. To accomplish this you would need a simple cross over Ethernet cable.

You can also connect the routers back to back via their serial ports. This would be more complicated. To accomplish this you would need some kind of cross over serial cable (I have done it with RS-232 and with V.35) Since the 1700 was doing Frame Relay over its serial interrface, you will probably need to configure the serial interrface on the 2600 for Frame Relay and also make the 2600 the Frame Relay DCE.

In either case you will need to configure the IP address of the interface on the 2600 to be in the same subnet as the address on the 1700.

This alternative is based on the assumption that the 1700 did not do things to filter data on its interfaces via access lists and did not restrict telnet via access-class on the vty ports. If the 1700 did have any restrictions on access configured then you would have to take that into account as you plan how you will access the 1700.

HTH

Rick

[TT0wnsend]

Using hyperterminal, I used the config-reg command to change booting from ROM monitor mode to boot from ROM. I was then able to configure a host name, an IP address and passwords. I have a configuration file that an previous consultant of ours emailed me that I can use to prepare this router for the T1 upgrade. How can I just copy this text file into the router's configuration? I will not be using a tftp server.

[Kevin Dorrell]

The simplest way, if the config is not too enormous, is to use the Edit->PasteToHost facility of Hyperterminal.

Kevin Dorrell

Luxembourg