mccullrr
Technical User
- Mar 6, 2006
- 71
What happens if you are getting vlan mismatch errors, but you do not fix them?
Thanks,
Becky
Thanks,
Becky
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Vlan Mismatch
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mccullrr
Technical User
- Mar 6, 2006
- 71
Thanks! I just noticed this error and didn't know if it has always been there or was the cause of some configuration I did??
I have a catalyst 4507 and port 46 is going to the LEM inside port of a packetshaper and port 48 is going to the LEM outside port. 46 is in vlan 501 and 48 is in vlan 600. The error I am getting is...
Description: Native VLAN mismatch discovered on GigabitEthernet5/48 (600), with Main_Hall.net.wlsc.edu GigabitEthernet5/46 (501).
So, you don't think it is anything I need to worry about??
Thanks!!
Becky
I have a catalyst 4507 and port 46 is going to the LEM inside port of a packetshaper and port 48 is going to the LEM outside port. 46 is in vlan 501 and 48 is in vlan 600. The error I am getting is...
Description: Native VLAN mismatch discovered on GigabitEthernet5/48 (600), with Main_Hall.net.wlsc.edu GigabitEthernet5/46 (501).
So, you don't think it is anything I need to worry about??
Thanks!!
Becky
The network will usually still work, but leaving it as is will consume all of the log files of the affected switches (which should be left available for other syslog messages).
The few times I have encountered the native vlan mismatch error was from a hard-coded access port interfacing with a hard-coded trunk port on the same link. Look at the switchport configuration on each side and see if there are any such discrepancies.
The few times I have encountered the native vlan mismatch error was from a hard-coded access port interfacing with a hard-coded trunk port on the same link. Look at the switchport configuration on each side and see if there are any such discrepancies.
You should go ahead and set the Native Vlan if you are using dot1q trunking. On a dot1q trunk as I understand it data that belongs to the native vlan is not encapsulated. The native vlan should match on both sides.
interface FastEthernet0/24
keepalive 10
duplex full
speed 100
switchport trunk encapsulation dot1q
switchport trunk native vlan 6
switchport mode trunk
interface FastEthernet0/24
keepalive 10
duplex full
speed 100
switchport trunk encapsulation dot1q
switchport trunk native vlan 6
switchport mode trunk
From Cisco Documentation
Significance of Native VLAN
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.
Significance of Native VLAN
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.
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