CISCO SF 300 8 Port Switch - Problems deleting tagged vlans from trunk port

[juleedev]

Hi there.  I have a Sf300 switch running firmware 1.2.7.76.

I've noticed that whenever I removed a tagged vlan from a trunk port, the native Untagged vlan is always reset to 1.

This seems to be a bug with the firmware.

Has anyone else run into this?  Is there a fix?

Thanks.

[Tom Watts]

Hi Jule, I'm not sure what you mean. By default, vlan 1 is the native and default vlan. You may change the native vlan if you make the vlan id the untagged member of the port. There is no such thing as a tagged native vlan. There is a such thing as a tagged default vlan.

Also, depending on what you're doing, you may be running in to macro issues since the macro will not automatically update the untagged native vlan. But there isn't enough information or scenario to determine this statement.

-Tom
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[juleedev]

Tom,

I've recreated the problem... please check out the series of commands below:

SAM-A1-SW-1#show interfaces switchport fa1

Port : fa1

Port Mode: Trunk

Gvrp Status: disabled

Ingress Filtering: true

Acceptable Frame Type: admitAll

Ingress UnTagged VLAN ( NATIVE ): 29

Port is member in:

Vlan               Name               Egress rule Port Membership Type

---- -------------------------------- ----------- --------------------

29                 29                 Untagged          Static       

70                 70                  Tagged           Static       

80                 80                  Tagged           Static       

Forbidden VLANS:

Vlan               Name              

---- --------------------------------

Classification rules:

Mac based VLANs:

  Group ID   Vlan ID

------------ -------

SAM-A1-SW-1#conf t

SAM-A1-SW-1config)#int fa1                                                                                                                                                                                           

SAM-A1-SW-1(config-if)#switchport trunk allowed vlan remove 80                                                                           

SAM-A1-SW-1(config-if)#exit                                                                                                              

SAM-A1-SW-1(config)#do show interfaces switchport fa1                                                                                    

Port : fa1                                                                                                                                   

Port Mode: Trunk                                                                                                                             

Gvrp Status: disabled                                                                                                                        

Ingress Filtering: true                                                                                                                      

Acceptable Frame Type: admitAll                                                                                                                   

Ingress UnTagged VLAN ( NATIVE ): 1                                                                                                               

Port is member in:                                                                                                                                

Vlan               Name               Egress rule Port Membership Type                                                                            

---- -------------------------------- ----------- --------------------                                                                                      

1                  1                  Untagged          System                                                                                             

29                 29                  Tagged           Static                                                                                             

70                 70                  Tagged           Static                                                                                             

Forbidden VLANS:                                                                                                                                                   

Vlan               Name                                                                                                                                            

---- --------------------------------                                                                                                                              

Classification rules:                                                                                                                                                   

Mac based VLANs:

  Group ID   Vlan ID

------------ -------

SAM-A1-SW-1(config)#

Notice how after i removed the tagged vlan 80, the system has changed my Untagged vlan from 29 to 1.

Any suggestions?

[Tom Watts]

Either because you're using GVRP or because the macro is updating and the native vlan on the macro was not added to specify that the native vlan should be 29.

-Tom
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[juleedev]

Tom, I've checked and we are not suing GVRP.  I'm not sure that I understand your comments about the macro...

Sorry, I'm just new to the networking world, so I apologize for being "thick".

Can you give a few more details about what you mean?

Thank you

[Tom Watts]

Hi Jule, here is a topic which gives a good visual about this

https://supportforums.cisco.com/thread/2177613

-Tom
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