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Configure etherchanneled trunk with dot1q encapsulation on a cisco 2950 switch

Hello All,

I have a cisco 2950 series catalyst switch. I setup port fa0/23 - 24 to be an ether-channel and a trunk, with the ether-channel being named Port-channel1.

I want to configure the trunk to use dot1q encapsulation. So, under Port-channel1 configuration i try to enter the command "switchport trunk encapsulation dot1q", and it doesn't take. In fact, here's what shows up when I use the help function:

Switch(config-if)#switchport trunk ?
allowed Set allowed VLAN characteristics when interface is in trunking mode
native Set trunking native characteristics when interface is in trunking mode
pruning Set pruning VLAN characteristics when interface is in trunking mode

Notice there is no "encapsulation" option.

So, can 2950's change encapsulatioin or do they always use ISL? If so, how can I change it?

thanks,
Mark

JFrederick29

Actually, the 2950 only supports 802.1Q so that is why the option to set encapsulation is not present.

fbrsupport

ASKER

Thanks for the quick reply... but check thiis out....

Switch(vlan)#show current
VLAN ISL Id: 1
Name: default
Media Type: Ethernet
VLAN 802.10 Id: 100001
State: Operational
MTU: 1500
Backup CRF Mode: Disabled
Remote SPAN VLAN: No

From the output, looks like ISL is being used.

ASKER CERTIFIED SOLUTION

Galtar99

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SOLUTION

JFrederick29

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fbrsupport

ASKER

Thanks for the link Galtar99!

JFred (kinda sounds like K-Fed, hahahahah, ok my mind is going on a tangent),
anyhow...

sh int trunk - didn't show anything
BUT
check this out:
Switch#sh int fa0/23 switchport
Name: Fa0/23
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: down (suspended member of bundle Po1)
Administrative Trunking Encapsulation: dot1q
....

It shows dot1q here!

thanks guys,
Mark

JFrederick29

The administrative/operational encap is what you should be looking at to verify.

Galtar99

Do the following show you what you expect to see?

show port channel
show etherchannel or show port group
show interfaces trunk

fbrsupport

ASKER

Here ya go galtar

Switch#sh port channel
^
% Invalid input detected at '^' marker.

________________________________________

Switch#sh etherchannel
Channel-group listing:
-----------------------

Group: 1
----------
Group state = L2
Ports: 2 Maxports = 8
Port-channels: 1 Max Port-channels = 1
Protocol: -

________________________________________

Switch#show interfaces trunk

Switch# (no output)