No uplink activity on 2960 48s

[BHconsultants88]

Hi all

Having a few problems getting the uplink configured on a port of a 2960 switch. Not getting activity light and interface Gi1/0/21 is showing down (this is where the uplink cable is patched into).

Could someone take a quick look at the config and point me in the right direction please?

Thanks

[cofee]

interface g1/0/21, are you trying to configure it as a trunk port? 

Please do the following :

* remove spanning-tree bpdu-filter enable command from this port. Unless you have a strong reason for it.

* if it's a trunk port, then remove spanning- tree port fast command and if an access port then remove switch port mode trunk . 

[Julio E. Moisa]

Hi

I agree with cofee@0400, those command lines should not be configured on both ends, once it is removed turn off and turn on the port and check connectivity. 

[BHconsultants88]

Thanks for your comments cofee. I'm still not seeing an activity light, I've tried it as access port and trunk. Is there any additional config I need to add in the vlan interface?

[cofee]

Please share output of below commands from both devices:

sh run interface xx (replace xx with the actual interface number)

sh int xx (replace xx with the actual interface number)

Also test the actual cable that you are using and the port on both devices to make sure that issue is not physical.

[Julio E. Moisa]

Hi

You could just add:

int g1/0/21
switchport trunk encapsulation dot1q  (the new devices has it implicit, so it is not needed)
switchport mode trunk
no shutdown

Now if you want to configure native vlan or filter the vlan traffic, you could use:

vlan 999
description NATIVE-VLAN

Int g1/0/21
switchport trunk native vlan 999   (on both ends)
switchport trunk allowed vlan vlan1, vlan2, vlan3....vlan N

The configuration should be the same on both ends to keep a standard and order.

* Is not good practice use the vlan 1 for native vlan, it should be other vlan and used for that specific role only. 

Hope it is useful

:-)