Switches, Hubs, and Modems

redundent link

Go to solution
Occasional Contributor

redundent link

i have a core switch 8206zl nd 2 2610 switches... i have a fiber link from 8206 to both of 2610 nd connect between to 2610 via utp link from uplink nd i enabel stp on 8206 nd both of 2610 by default when ebalbe stp it enables MSTP on all of them i would like to make both fiber like forwarding nd utp between 2610 block should i config any thing more or this will done automatic all links 1 g fiber nd utp ...
Pieter 't Hart
Honored Contributor

Re: redundent link

So you got two switches (8206 and 2610) interconnected with both a fiber and a utp port?

What your looking for seems to be port-trunking, either configure manually or use LACP.
From STP point of view, a port-trunk behaves as a single link, both ports are active.
Respected Contributor

Re: redundent link

so the 2* 2610 are connected to 8206zl switch and you want the fiber link from the 8206 to the 2610 to be the forwarding.

In this case just make sure that the 8206 is the root switch for the MSTP.

One more thing if you are not really going to use the MSTP instances is to change it to RSTP using the command
#spanning-tree force-version RSTP-operation

Then assing the 8206 switch as root by assinging priority of 0

#spanning-tree priority 0

dont forget to save the config.
#write memory.

Mark Wibaux
Trusted Contributor

Re: redundent link

You need to increase the "cost" of the link between the two 2610 switches.

Assuming you have 2610-24 switches and are linking them with gigabit using port 25 then you would run the following command at the CLI of the switch. You need to run this on both 2610 switches. If you are using a different port then change the "25" in the command.

conf (to enter configuration mode)
spanning-tree 25 path-cost 50000
wr mem (to commit the change to flash)

The default cost for a 1Gb link is 20000. By increasing the cost of the link between the 2 switches, spanning tree should default to using the gigabit fibre links back to the 8206zl switch instead.
Also a good idea to set the 8206zl as the root of the spanning tree using the "spanning-tree priority 1" command.

Grab a copy of the "Advanced Traffic Management Guide" for your switches to get further information on spanning tree.
Occasional Contributor

Re: redundent link

dear sirs ,
i would like to thnx all for u for your help it's working now really thanks