BCMSN: sh int fa# switchport -> operational mode?

mzinz

Hi all,

I've begun studying for my BCMSN and ran into something odd today. I have two switches set up, both are set to dynamic desirable.

When running sh int fa0/16 switchport, I get the following output:
XX-C2950_A#sh int fa0/16 swit
Name: Fa0/16
Switchport: Enabled
Administrative Mode: dynamic desirable
Operational Mode: static access
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: native
<snip>

There is only one VLAN on this network, so is it not trunking because trunking wouldn't be necessary? It seems to me that if both sides are dynamic desirable, it would automatically establish a trunk...

Why is it operational mode: static access??

cisco_trooper

What does the far end interface look like?....

Do you have this interface in access mode?

Show us the interface configs...

mzinz

cisco_trooper wrote: »

What does the far end interface look like?....

Do you have this interface in access mode?

Show us the interface configs...

I realized what the issue was.

I had mixed up my CDP ports and was looking at the switchport connected to a router. After looking at a switchport connected to a switch, I did notice that OP Mode was indeed "trunk".

Here's a new question: If I configure the router with subinterfaces and encap dot1q, will the switch change from OPMode access to OPMode trunk? I'm assuming yes.

kalebksp

mzinz wrote: »

If I configure the router with subinterfaces and encap dot1q, will the switch change from OPMode access to OPMode trunk? I'm assuming yes.

I doubt that routers send DTP packets, so they wouldn't negotiate a trunk. I'd lab it up to double check.

cisco_trooper

kalebksp wrote: »

I doubt that routers send DTP packets, so they wouldn't negotiate a trunk. I'd lab it up to double check.

I concur...