Cisco 2811 unreachable gateway over second HWIC-4ESW

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Jul 25th, 2010
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We purchased some HWIC-4ESW modules for our 2811. I installed two on the Cisco 2811 router.

On the router I configure interface VLAN 1 with IP-address I used on laptop like default gateway.

From my laptop I can ping gateway only if I connected to first HWIC (in HWIC0 slot). If I uninstall first HWIC and connect my laptop to second HWIC (in HWIC1 slot) I can ping gateway again. So only one HWIC-module can work at once.

What I do incorrect? Can this modules work together?

Correct Answer by mlund about 6 years 9 months ago

Hi Alexander

In this coniguration guide it states that You have to configure "stacking-partner" to get the crossover cable to work.


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Overall Rating: 5 (1 ratings)
Kevin Brennan Mon, 07/26/2010 - 02:27
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Hi Alexander,

If you have 2 HWIC-4ESW's in the one chassis, you must connect them together with a crossover ethernet cable. Between the two cards, they will only have one internal L3 connection to the router.

I'd also check your IOS version(s) and the slot numbers.



Alexander Belonogov Mon, 07/26/2010 - 07:26
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Thanks for your answer Kevin.

I tried to connect them together with a crossover cable and I have no success. Gateway doesn't ping over second HWIC.

In data-sheet from your link I see next:

Table 3. Supported Platforms for 4- and 9-Port Cisco EtherSwitch HWICs

Chassis4-Port Cisco EtherSwitch HWIC
Cisco 2811Yes, 2 HWICs per router

And in "Cisco HWIC-4ESW and HWIC-D-9ESW EtherSwitch Interface Cards"

In chapter "Prerequisites for Installing Two Ethernet Switch Network Modules in a Single Chassis" I see that module must have an optional Gigabit Ethernet expansion board installed and Ethernet crossover cable must be connected to the  two Ethernet switch network modules using the optional Gigabit Ethernet  expansion board ports. There is no place for optional ports on HWIC-4ESW.

So I can not understand how I can use two HWIC-4ESW on Cisco 2811 router?

Kevin Brennan Mon, 07/26/2010 - 07:38
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Hi Alexander,

Are the switchports configured? Could you post your configuration?

Also, "show vlan-switch" , "show inventory" and "show interface switchport" might be useful.

I think the snippet you quoted refers to a NM switch module and not a HWIC switch module. If there are two HWIC-4ESW in a chassis, they will need a cross over between them.

Have you confirmed that the HWIC is supported by your IOS?.


Alexander Belonogov Tue, 07/27/2010 - 05:40
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Thanks Mikael.

After using commands from guide I get required functionality - gateway pinged.

I correct understand: always if I want use two HWIC-4ESW I have to lose two interfaces for stacking? Second HWIC will not work without stacking?

mlund Tue, 07/27/2010 - 08:00
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Hi Alexander

I'm glad my answer solved Your problem, and You are completley right  in Your understanding of the stacking.



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