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Setting up the Cisco 2612 as a Token Ring Bridge

Note: This is a basic quick start for Token Ring to Ethernet bridge using the Cisco 2612. In my setup 192.168.73.0 is my home network and 192.168.123.0 is the tokenring network. More complete information can be obtained at

Cisco 2612 Quick Start Guide.
1. Connect the Cisco 2612 as follows:
     The RJ45 connector of the serail cable from the PC goes to "Console" on 2612.
     A CAT-5 cable goes from the "TokenRing0/0" port of the 2612 to the concentrator.
     A Cat-5 cable goes from the "Ethernet0/0" port of the 2612 to your home network router.

2. We will set the configuration using a terminal program on our PC. On Windows try HyperTerm, newer versions of Windows do not have this program but XP and earlier do. On newer Windows obtain Putty to talk to the serial port. On linux the most popular is minicom. After intalling it ("sudo apt-get install minicom" on Unbuntu) run it with "minicom -s -o" the first time. The -s will take you into setup in which you typically want port set to "/dev/ttyS0" and port settings to 9600 baud, 8 data bits, 1 stop bit, no parity. After the initial setup run you can start it with "minicom -o", the -o says do not issue modem initialization strings.

3. We are going to start by reseting the router to factory specs. When you start the comm program if you do not get a "SomeName>" prompt from the router hit enter. Now at the "SomeName>" prompt enter "show version". The last line displayed should have: Configuration register is 0x2102. Type "enable" to get command ability. If there is some other value type "config-register 0x2102". Type "write erase" to clear memory. Reload the router with "reload". If you get a message asking wether or not to save the configuration, reply "no".

4. The router will reload. You will get a message saying "Press RETURN to ge started", press enter. It is probable that it will try to load a configuration from the network (displays tftp messages indicating failed load attempts from the network gateway and/or 255.255.255.255), ignore these messages and type "enable", followed by "configure". It asks from where, and the default is terminal.

5. Let's get rid of the tftp attempts first. Key "no service config" followed by Cntrl-Z. This will activate the previous command. Now we key "configure" again to continue.

6. Now the ethernet. Type "interface Ethernet0/0". Then "ip address 192.168.73.200 255.255.255.0". Followed by "exit".

7. Now the tokenring. Type "interface TokenRing0/0". After the new prompt appears "Router(config-if)#", type for example "ip address 192.168.123.1 255.255.255.0" to set the ip address/subnet mask for the tokenring interface. Then we need to set the ring speed with "ring-speed 4". Then "no shutdown" followed by "exit".

8. It is time to save what we have done with "copy running-config startup-config". It will ask for a destination filename which is startup-config, the default if you just hit enter.

9. You will have to add a permanet route somewhere. If your home network router has the ability to add routes I would suggest that method as it will then work with any computer you have. Otherwise on the Windows machine you intend to use for Herucles, at a command prompt type "route -p add 192.168.123.000 mask 255.255.255.0 192.168.73.200". On Ubuntu open a terminal and type "route add -net 192.168.123.0 netmask 255.255.255.0 gw 192.168.73.200 dev eth0".

10. At this stage you should be able from your pc to ping the tokenring adapter in the 2612 with "ping 192.168.123.1" and the 3174 with it's tokenring ip address if you have it setup. If not something has gone wrong. You can check your settings with various incantations of the show command. Try "show config" to get a summary. If you have followed the tutuorial correctly please email me with the symptoms and I will try to help or find the bug in my tutuorial.


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