L2 ether channel switchover

[ncnaveen_arasu]

                   HI,

HOw switchover will happen in L2 and L3 ether channels whe nport fails in a bundle.

Even we set the priority to the ports it is taking by default the highest interface number in the port-channel as a path for forwarding.

KAR-L3#test etherchannel load-balance interface port-channel 1 ip 10.161.20.193 10.161.20.194

Would select Gi1/0/18 of Po1

I have configured gi1/0/17 as prioroty 150 ans gi1/0/18 as default to 128 in PAGP. So in this case it has to take gi1/0/17 right ?

BUt from the above output it os taking port 18. Why it is so.

How a port-chanel comes to know the link is down in a bundle as we aggregate the Ether links and which will not go down untill physically removed. So wether traffic will get interrupted.

Please guide me.

Thanks in regards,

Naveen

[Reza Sharifi]

Hi,

The load balancing can't really be controlled by using priority. When using PAGP:

the active port is selected       based on the priority of the links on the switch that has the higher Ethernet       address. When two ports on the switch with the higher Ethernet address have the       same priority, the port with the lower ifIndex is selected.

More info here:

http://www.cisco.com/en/US/tech/tk389/tk213/technologies_tech_note09186a0080094714.shtml

HTH