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RSTP Problem

 
Christoph Zach
Occasional Contributor

RSTP Problem

HI all

I Have a Problem with RSTP
We have 14 Switches, one 5308XL, one 2626, and 12 2524, on all switches RSTP is enabled.
The 5308XL is the Root Bridge
Between the 5308 and the 2626 we have 2 Uplinks.
One Link has Pathcost 200000 and one has Pathcost 850000 at the 2626.
RSTP is running, and at the 2626 one Port is blocked by RSTP.

But my Problem ist that the Blocked Port at the 2626 is in Role "Alternate", shouldn't it be in Role "Backup" ?
All redundant links to the same segment should be "Backup Ports", not "Alternate ports".

5308XL Software Version E.10.27
2626 Software Version H.08.92

1 REPLY 1
Matt Hobbs
Honored Contributor

Re: RSTP Problem

This link may help you clarify the spanning-tree roles:

http://www.cisco.com/warp/public/473/146.html

An alternate port is a port blocked by receiving more useful BPDUs from another bridge

A backup port is a port blocked by receiving more useful BPDUs from the same bridge it is on

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