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6500 port-channel question

I am port-channeling between 2 6500 switch with Sup720's running IOS with the following code: s72033-jk9sv-mz.122-18.SXD7

The original configuration, is listed below.

Int port-channel 1

No ip address

Logging event link-status

Logging event bundle-status

Logging event trunk-status


Switchport encapsulation dot1q

Switchport native vlan 2

Switchport trunk

I wanted to remove a VLAN from the trunk using the following command.

switchport trunk allow vlan remove 206

when I typed in the command, the port-channel, the went down, and remained down until I typed in the command on the second switch.

Po1 went down, on the first switch,

Po1A came up on the first switch

Po1 went down on the second switch, Po1B came up on the second switch.

Is there something I can do to prevent this from happening in the future?



Community Member

Re: 6500 port-channel question

Unfortunately, no. The range of allowed vlans must be the same on both sides.


Re: 6500 port-channel question

It operated normally all parameters must match on both sides for the channel to work . You get a short period to get it in on both sides but then the channel will go down if they don't match . Best thing to do in cases like that is to telnet into both switches and get into the int port channels and make your changes to both sides as close as possible timewise . it should keep the port up. Haven't seen them referenced as PO1A and P01B what is that ? Anyone see that before ???

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