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ifconfig -a doesn't show the second interface?

Hello all, I'm trying to figure out where someone plugged our sensor's monitoring interface in so I can span the port. Unfortunately no one described the interface and I can't find any docs with that info. So I figured I could grab the MAC address from the box, then find it in the switch's mac table (if it is there, which I'm not at all sure it is). But when I do an ifconfig -a I get:

lo0: flags=1000849<UP,LOOPBACK,RUNNING,MULTICAST,IPv4> mtu 8232 index 1

inet netmask ff000000

iprb0: flags=1000843<UP,BROADCAST,RUNNING,MULTICAST,IPv4> mtu 1500 index 2

inet netmask ffffff80 broadcast

ether 0:90:27:73:12:d5

Does anyone know how I can get info on the monitoring interface? And why was this functionality taken out? Security? (or is my sensor simply not finding the NIC?)

Cisco Employee

Re: ifconfig -a doesn't show the second interface?

ifconfig -a only shows "plumbed" interfaces. We deliberately do not plumb the sensing interface for security reasons (which you proved being unable to find it) You could plumb the interface temporarily, get the info you need then unplumb it.

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