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Serial Interface Problem on Router

How can I check the BACKGROUND IMAGE  & CHANGE IT ON 1841 & 2620 ROUTERS;     .....   IF :-

See my attached txt file.

My 1841 router will not appear to accept DOUBLE WIC2T links to 2 x 2620 routers where the DCE / DTE 'polarity' is swapped on both connections. Even two WIC2T cards used on 1841.

I have tried using the same WIC2T card & different NEW WIC2T cards on the 1841/ 2620 routers. Only one WIC2T card on 2620s used. Cabling, DCE/DTE terminals are correct & basic cmds seem correct ( bandwidth, clockrate, shutdown etc).

The 2nd DCE connection from the 1841 router doesnt work but the DTE 1841 connection on another card does connect to another 2620.

If anyone can help. This is the first lab exercise in the CCNA EXPLORATION LAB.

The WIC2T card on the DCE 1841 to DTE 2620 flashes on/ off during reboot. (weird....PC made a strange noise...but no tcp/ip connection to router from pc) ????


cadet alain


try another model or if it is a PT bug or limitation then do it on real gears or GNS3.



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Hi. Thanks but  what is a PT bug , Real gears or GNS3? I havent heard of these.

If its a PT bug; please explain how to fix it on the 1841 router.

What is real gears / GNS3? Are they rackspace or simulators? If so whats the cost?

Do you think I should swap the 1841 router for a 2620XM router ( with WIC2t card)  ; will that work. I suspect it could be WIC2T card incompatibility perhaps; but the cards come up on ''sh run''.

Does this happen on a router; why & for what reason?

Shouldnt a 1841 router be able to handle 2 concurrent serial connections with DCE on one s0/0/0 port & DTE on other s0/0/1 port?

Could it be a Priority or DHCP thing?

I have so many many more labs to go & need desperately to fix this. Will it only be a problem on the 1841 & not the 2620's ? This is very concerning on a first lab.


Bug= software problem that limits the usage of PT for certain tasks

Real gear= real hardware devices

GNS3 = emulator different from PT= simulator but doesn't handle ISRs like 1841,2800 and only support 15.0M IOS for 7200 or 7600 routers, other models have only support for 12.x IOS. GNS3 is free but you have to find the IOS for which you should normally pay a licence.

On real devices there could be a hardware limitation but you'll have to search for this on Cisco Site.


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Hi Can a 1841 router handle 2x WIC2T cards?


If the background image failed on the 1841 how do I check it & change it? What if the 2nd interface on the WIC2T card failed? Can I test for these?