1841 and 2 HWIC-4ESW cards, the one on slot1 not sending data.

[accarda]

Hi everyone,

I have couple of HWIC-4ESW installed in my 1841, even though up to now I have used only the first installed on slot 0.

Here below is the output from sh inventory:

r0gw#sh inventory

NAME: "chassis", DESCR: "1841 chassis"

PID: CISCO1841 , VID: V05 , SN: FCZ113637U2

NAME: "4 Port HWIC on slot 0", DESCR: "4 Port FE Switch"

PID: HWIC-4ESW , VID: V01 , SN: FOC134917GF

NAME: "4 Port HWIC on slot 1", DESCR: "4 Port FE Switch"

PID: HWIC-4ESW , VID: V01 , SN: FOC134916U7

Today I tried to enable VLAN3 on one port of the other card on slot 1 and after all config was done (similarly to what I have done already on the first card with VLAN1 and VLAN2), I can't ping anything on the new defined subnet.
I have tried to define VLAN3 on all 4 interfaces 0/1/0, 0/1/1, 0/1/2 and 0/1/3 just to try the issue was with a particular interface, but the issue was on all of them.

So I free up one interface from the card on slot 0 and defined VLAN3 on that, and all is working fine.

At this point my question: is there an issue with this second card, or is my 1841 not able to manage this second card ?

Is there any command that can help in understanding where the issue lies ?

Thanks in advance for any suggestion that you can provide.

Armando

[Richard Burts · Accepted solution]

When you have a single HWIC-4ESW card it communicates using the router backbone. But when you add a second HWIC-4ESW card it can not communicate using the router backbone. The solution is to connect one port from the second card to a port of the first card. Here is a link that discusses this and has an example of how to configure it. I hope you find it helpful.

https://community.cisco.com/t5/switching/two-hwic-4esw-cards-can-they-work-together-in-the-same-vlan/td-p/2727628

HTH

Rick

[accarda]

Thank you Richard to point that post out.

I would not have guessed that the second card would have needed such setup to work, good to know.

Armando.

[Richard Burts]

Armando

I agree that if the first card works using the backplane that it would be logical that the second card would work the same way. But there are technical issues with that and the solution is to connect ports on both cards so that the second card can access the backplane through the first card. I am glad that my explanation was helpful. Thank you for marking this question as solved. This will help other participants in the community to identify discussions which have helpful information. This community is an excellent place to ask questions and to learn about networking. I hope to see you continue to be active in the community.

HTH

Rick

[accarda]

Thank you Rick and I totally agree with you about the value of this community.
Even though I registered only last week, however I was able to solve many of my doubts about several things that I wanted to implement in my config by searching and reading in this community several times.
Regards,
Armando.