Wireless LAN Controller

[nickh2022]

Hello Everybody,

I have a WLC 4402 plugged into a Catalyst 4507R. My problem is I am unable to ping the WLC from a different VLAN. While reading the document about best practices, it mentions that the fiber port should be configured using dot1q encapsulation but when I try to configure that, I do not get encapsulation as an option. The wierd thing is, other ethernet ports on the switch do have encapsulation configured. Please advise!

[jeff.kish]

Some versions of IOS do not support ISL, so Dot1q is the only option for encapsulation. As such, it does not give you the option to configure encapsulation.

Rather than checking encapsulation, check to make sure the port is in trunk mode. Run the "switchport mode trunk" command on the switchport and see if that works for you.

I will say that this sounds more like a routing issue than anything. By saying that you can't ping it from other VLANs, are you implying that you can ping it from the same VLAN? If so, it sounds like your network isn't able to route to the controller.

A few questions - is this a new subnet? Can the 4507 ping the WLC? Can you ping it from the 4507 from different VLAN interfaces (will require an extended ping to test). Can you ping any other devices on the same subnet as the controller from different VLANs?

Also, make sure you're not trying to ping the AP Manager interface. This interface does not respond to pings.

Thanks,

Jeff

[nickh2022]

The IOS version is 12.2 (25).

I do have “switchport mode trunk" configured on the port already.

I can ping the WLC on the same VLAN. My computer for example is on a different VLAN and I can not ping the WLC, however from my PC I can ping other devices on the same VLAN as the WLC

It is not a new subnet. I can ping the WLC from the 4507

I am pinging the management interface and it is responding to pings.

[tkhan]

Check for proper mask and default gateway configured in the WLC.

[nickh2022]

The SM and GW have the correct information. Some of my antonomus AP's have the exact same information as far as SM and GW and I can ping those devices.

[tkhan]

Check your switchport config for the proper "native vlan" assignment for the controller.

[nickh2022]

I have set the "native vlan" to the appropriate vlan that the controller is located on...Still no communication.

Here is what I have configured on the Fiber port that the controller plugs in to

interface GigabitEthernet6/15

description ***Wirless Controller***

switchport trunk native vlan 20

switchport mode trunk

Now, when I set the native VLAN, I lose the ability to ping the WLC from the switch

[tkhan]

The ap-manager and management interfaces should both be, "untagged", for VLAN Identifier. You set this on initial setup of the WLC.

[nickh2022]

Ok..right now I do have them "tagged" Do you believe that if I set the Native VLAN and change those two interfaces to "untagged" that it may resolve my issue?

[jeff.kish]

It sounds like a potential VLAN mismatch. Best practice is to have your management interface configured for untagged traffic, so I would advise that.

Is your management interface on VLAN 20? If so, your other option would be to remove the native VLAN statement from the switchport. But I would advise making the change on the controller itself.

[nickh2022]

Ok...I changed the two interfaces mentioned above to untagged and added back the Native Vlan statement.

However, I still can not ping the WLC from outside its own VLAN.

I setup switchport trunk allowed for the two VLAN's, still no communication.

[jeff.kish]

Can you ping the controller's default gateway from the controller?

[nickh2022]

Yes, I can.

[tkhan]

Either clear your arp tables in your router and/or reboot your controller.

[nickh2022]

I've rebooted the controller several times.

Im just confused as to why I can not communicate.