I have bought a Cisco 1841 with an additional ethernet adapter (so it has 3 ethernet interfaces). But when I enter the router operative system I see only 2 ethernet interfaces, the budled FastEthernet0/0 and FastEthernet0/1. It seems that the current operative system of the router can't recognize the additional adapter. I can't find what version of the operative system or additional software is needed (at this moment the operative system is 12.4 but I can't see what specific version of 12.4). Please, can anyone help me ?
Thanks a lot.
You need to upgrade your IOS. You have 12.4-3 whereas you need at least 12.4(15)T.
Hardware support for the HWIC-1FE card was added in the T train in 12.4.