[c-nsp] Problem Configuring Cisco 7000 Router

[Marty Adkins]

kmattar at cs.bu.edu wrote:

> I am configuring a small local network here at Boston University. Among the
> components I am configuring are four Cisco 7000 routers. I am currently having
> trouble with one of the routers. I cannot connect to it through its serial port.
> I am using Hyperterminal, and for some reason it doesn't detect anything on the
> other end of the connection! I didn't have any problems configuring the other
> routers, which are identical. None of the interfaces on the router are
> configured either so I can't telnet to it. Is there a way to configure just one
> interface on this router and enable telnet? 
> 
> Best regards,
> Karim

It's possible that the console port EIA/TIA receiver chip has been damaged
by static electricy.  But before you move on replacing it, consider the
possibility that the existing config is keeping it mute (e.g., 'no exec').

I'm assuming you've already tried varying the HT speed from 1200 to 19200
(and disconnected and reconnected after each change!).  So try powering up the
router, wait about 15 seconds, and issue a BREAK from within HT.  Watch the
RP lights as you do this and notice if it seems to have any effect (does the
router halt?).  If so, then vary the HT speed from 1200 to 19200 and see if
you can talk to it.

Since it's a 7000, the boot code is a full image in ROM.  If it's v10.0 or
later, then it uses a software-based configuration register.  If older, then
move the jumper on the hardware configuration register from pin 1 to pin 15
(maintenance mode) and try again.

If there is a valid config being executed upon boot up, you should be able
to connect a protocol analyzer to an Ethernet interface and sniff.  Look
for gratuitous ARP replies indicating the configured IP address.  If you
find that, configured a workstation to be in the same subnet and attempt
to Telnet.  If your capture finds the router attempting BOOTP, then you
could satisfy it with a DHCP server and go from there.

HTH,
- Marty