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New Member

is this considered NATIVE VLAN?

Greetings All I know that the Native VLAN in a switch is VLAN 1

Since my access points needs a native vlan to perform multiple SSID and VLANS etc. If the ACcess pont is sitting on VLAN 20 with an ip address assinged to it from that vlan does that mean VLAN 20 is native?? Sorry for the ignorant question but I am trying to do multiple ssid etc

4 REPLIES
Hall of Fame Super Red

Re: is this considered NATIVE VLAN?

Hey Pete,

Have a read of this good doc, here is an excerpt;

The routers and switches that make up the physical infrastructure of a network are managed in a different method than the client PCs that attach to that physical infrastructure. The VLAN these router and switch interfaces are members of is called the Native VLAN (by default, VLAN 1). Client PCs are members of a different VLAN, just as IP telephones are members of yet another VLAN. The administrative interface of the access point or bridge (interface BVI1) are considered and numbered a part of the Native VLAN regardless of what VLANs or SSIDs pass through that wireless device.The switchport config might look like this;

switchport mode trunk

switchport trunk encapsulation dot1q

switchport trunk native vlan 1

switchport trunk allowed vlan 1,10,30

Where vlan 1 is Native and vlan 10 and 30 will be associated with SSID's.

When you use an IEEE 802.1Q trunk port, all frames are tagged except those on the VLAN configured as the "native VLAN" for the port. Frames on the native VLAN are always transmitted untagged and are normally received untagged. Therefore, when an AP is connected to the switchport, the native VLAN configured on the AP must match the native VLAN configured on the switchport.

Note: If there is a mismatch in the native VLANs, the frames are dropped.

This scenario is better explained with an example. If the native VLAN on the switchport is configured as VLAN 12 and on the AP, the native VLAN is configured as VLAN 1, then when the AP sends a frame on its native VLAN to the switch, the switch considers the frame as belonging to VLAN 12 since the frames from the native VLAN of the AP are untagged. This causes confusion in the network and results in connectivity problems. The same happens when the switchport forwards a frame from its native VLAN to the AP.

From this good doc;

Using VLANs with Cisco Aironet Wireless Equipment

http://www.cisco.com/en/US/products/hw/wireless/ps4570/products_configuration_example09186a00801d0815.shtml#vlanap

Hope this helps!

Rob

Please remember to rate helpful posts.........

New Member

Re: is this considered NATIVE VLAN?

i Rob - thank you for taking the time to reply. Howver for the most part I understand what you are sayin. Currently I have all of the vlans trunked. My situation is this.

My Access points has (2) SSID's One is "mapped" to vlan 100 (non protected from a DSL Connect from local telco) Other vlan which is called 20 is sitting on a network of 192.168.199.x. My dhcp server dishes out tose. but my dsl on vlan 100 dishes out 192.168.1.x Now I think something maybe wrong with that..

Cause (A) the broadcasted SSID is not being "broadcasted"

And B i am not sure if the subnet is going to work correctly cause the ip address of the access point is 192.168.199.210

Perhaps I am confusing us all.

Another words the access point sits on vlan 20 but I walo want to vlan 100 from dsl to connect to it.

hints tips or tricks???? Anyone??

New Member

Re: is this considered NATIVE VLAN?

To support multiple VLANs on an autonomous AP, you need to have an 802.1q trunk connection to the switch.

The tagged VLANs should be used to carry your traffic for the SSIDs on the radio(s). This traffic is bridged from the Ethernet interface to the Dot11 radio interface.

The Untagged VLAN (or Native VLAN) is supposed to be used for AP management. This untagged VLAN doesn't get propogated to the radios as per best practices. This untagged VLAN is bridged to interface BVI1. Obviously, you could use static IP addresses on this interface as well.

New Member

Re: is this considered NATIVE VLAN?

I thought it was. However here is a show vlan command from the AP:

Virtual LAN ID: 1 (IEEE 802.1Q Encapsulation)

vLAN Trunk Interfaces: Dot11Radio0.1

FastEthernet0.1

This is configured as native Vlan for the following interface(s) :

Dot11Radio0

FastEthernet0

Protocols Configured: Address: Received: Transmitted:

Bridging Bridge Group 1 309632 336857

Bridging Bridge Group 1 309632 336857

Virtual LAN ID: 100 (IEEE 802.1Q Encapsulation)

vLAN Trunk Interfaces: Dot11Radio0.100

FastEthernet0.100

Protocols Configured: Address: Received: Transmitted:

Bridging Bridge Group 100 2919 5792

Bridging Bridge Group 100 2919 5792

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