Native trunk vlan

[workmen]

Hi All, 

I am having a problem discovering an AP in WLC everytime I configure its connection in the switch as trunk native vlan 306 which is I think is the standard. It only works on switchport access vlan 304. When I run switchport interfaces trunk, it shows that vlan 306 is allowed on that particular port and is reachable. I do not have problem having that native vlan configuration in other floors. Am i missing something. 

Thank you very much in advance! 

[Arshad Safrulla]

Hi,

Check whether your switch has "dot1q tag vlan native", if yes it will not work as switch will tag the native vlan.

Use "no dot1q tag vlan native" to disable native vlan tagging.

[balaji.bandi]

what is the config on ther ports ? is this only issue with AP also any Access devices ?

what switch model and IOS running ?

[workmen]

3 3800 AP's are connected to interfaces g1/0/5 - 7 with switchport acess vlan 304, switchport mode access configuration. When I changed it to switchport trunk native vlan 304, the APs are not discoverable in WLC. I was hoping to trunk it but it doesnt work

[balaji.bandi]

. When I changed it to switchport trunk native vlan 304, the APs are not discoverable in WLC. I was hoping to trunk it but it doesnt work

post show run interface x/x config ?  why you need Trunk ?

what mode AP configured ?

[workmen]

Hi All, 

This is the configuration of the switch

VLAN 304 = 10.170.220.X/24

VLAN 305  = 10.122.5.X/24

VLAN 306 = 10.122.6.X/24

interface GigabitEthernet1/0/11

switchport trunk native vlan 304   => This is the configuration that makes the AP not discoverable in WLC

switchport mode trunk

I also tried this:

interface GigabitEthernet1/0/11

switchport trunk native vlan 306   => same as above not discoverable in WLC

switchport mode trunk

So i tried

interface GigabitEthernet1/0/11

switchport access vlan 304   => This one works and discoverable in WLC

switchport mode access

The Switch is 9300 POE

with SVI 304, 305 and 306

AP is 3800 configured as flexconnect mode

I have to tag the SSID with VLANS 304-306 so I enabled vlan support in the flexconnect tab

How can I tag it with different VLANS in the WLC if in the first place the port to where it is connected is not configured as trunk?

but if I trunk the port it is not discovered in WLC.

If I configured it as access port it is discoverable in WLC, but I if I enable the flexconnect and vlan support I got A 169.x.x.x 

TIA

Thank You Very Much

[balaji.bandi]

Not sure , what IP address WLC connected VLAN, when you WLC not discoverable means, AP get IP address, what IP address you get it ?

The Native is the vlan that is not tagged with a vlan ID on an 802.1q trunk. All other vlans traversing the trunk are tagged with a vlan ID. Using the trunk allowed command you specify the vlan number or  vlans are allowed over the trunk link,

cisco default native vlan is 1

try below config :

interface GigabitEthernet1/0/11

switchport trunk encapsulation dot1q

switchport trunk native vlan 304

switchport trunk allowed vlan  304

switchport mode trunk

[Scott Fella]

Like what others have mentioned, post your switchport configuration.  From what you mentioned, "I configure its connection in the switch as trunk native vlan 306 which is I think is the standard. It only works on switchport access vlan 304." 

What do you mean you think it's standard?  If your access points management vlan is 304, then your native vlan, if you are to go from access port to trunk, should also be 304.  The management for all Cisco access points should not be tagged, which means, native vlan.  

If your "standard" for all trunk ports uses native vlan 306, then your ap will need to be managed from vlan 306 and the ap will get an ip address from 306 and also will need to be reachable from that vlan.

[workmen]

Hi Sir, 

What I meant in the standard is that the ports to where the AP's are connected should be configured as trunk but I could be wrong.

Yes the management VLAN is 304 and the native vlan should be 304 but the thing is there is a Layer 2 switch in the other floor with management VLAN 305, but it works even if i  configured the port as trunk native vlan 306.

the switch is 9300

SVI

VLAN 305 = 10.122.5.X/24 Management VLAN

VLAN 306 = 10.122.6.X/24 

interface GigabitEthernet1/0/41

switchport trunk native vlan 306  = The AP got at an IP address 10.122.6.X and is discoverable in WLC 

switchport mode trunk

AP is 3800

[Scott Fella · Accepted solution]

It doesn’t matter what ap you have. The native vlan is the vlan in which the ap needs to be on. If for example you set the port to access vlan 306 and the ap doesn’t join, then you have an issue with your vlan 306 not being reachable to the controller.  If the ap can join the controller when you use an access port, then using the native vlan with that same vlan you set as access should work. 
So change the port to access vlan 306 and see if the ap joins. If not then you have problems on your infrastructure or it’s not properly configured. 

[workmen]

Hi Sir,

I already tried the access vlan 306 but same thing happened, it cannot join the WLC though it is reachable on both sides, from WLC to VLANs 304-306 there is no problem on reachability, I already checked the access-list and it shouldn't be the problem but like what you said it could be the network infra because it is quite strange for me. Thank you very much for all your help. 

[balaji.bandi]

try the suggested config and let us know if that works?