CISCO1921/K9 WIC Slot 1: UNKNOWN 4 Port GE Switch

[z3d3]

I have two cards installed "4 Port GE Switch" PN: 74-7105-01 on CISCO1921. Unfortunately, if there are two pluged in, then only one works in port EHWIC0 and the second one has an unknown status.

        WIC Slot 0:
        4 Port GE Switch
        Hardware Revision        : 1.0
        Part Number              : 74-7105-01
        Board Revision           : E0
        Deviation Number         : 0
        Product (FRU) Number     : EHWIC-4ESG
        Version Identifier       : V01

        WIC Slot 1:
        UNKNOWN
        Hardware Revision        : 1.0
        Part Number              : 74-7105-01
        Board Revision           : E0
        Deviation Number         : 0
        Product (FRU) Number     : EHWIC-4ESG
        Version Identifier       : V01

If I remove the card from EHWC0 then EHWC1 starts working properly.

[GRANT3779 · Accepted solution]

Hi,

This seems to be the correct behavior. The Router only support 1 of these modules -

https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/qa_c67-612908.html

Q. Why does the Cisco 1921 Integrated Services Router support only a single EHWIC switch module?

A. Unlike the Cisco 1941 and Cisco 2900 and 3900 Series ISRs, the Cisco 1921 platform does not have a backplane switch. The internal Gigabit Ethernet link of the EHWIC switch is connected directly to one of the internal CPU Gigabit Ethernet ports over a serializer/deserializer (SerDes). Thus the Cisco 1921 supports only one EHWIC switch module.