Changing access link to a trunk

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Jun 17th, 2009
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Has anyone tried to change an access link, carrying live traffic, to a trunk.

I need to do this soon and would like to learn from others who have experience with this - is there a procedure out there or steps I can follow?

This currently carries traffic so I need to prepare well. I think the transition should be very fast and that the traffic will only have a short interruption - right?

Thanks for helping!

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paolo bevilacqua Wed, 06/17/2009 - 23:44
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Yes, right.

Jon Marshall Thu, 06/18/2009 - 04:49
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Which version of STP are you running ? ie.

PVST+ = 50 seconds

RPVST+ = < 5 seconds

MST = < 5 seconds

Be aware that changing from an access port to a trunk may well involve an STP reconvergence and it will affect all vlans that you are allowing across that trunk link.

I would always recommend out of hours for doing anything that can have an affect on STP.


John Blakley Thu, 06/18/2009 - 06:01
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I agree with Jon. I've had to do this during production and I lost my telnet session to the switch. It was quick, but I noticed it. =)




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