Port Issue

[JJ]

Hi All,
When am trying to connect my 470-48T switch to my 8610 my ports gets shutdown after few seconds, My network is two l3 connected in VRRP and when i am connecting my l2 to both the l3 switch my l3 ports shutdowns. Can anyone tell me why this is happening.

Regards,
JJ

[Jon Hurtt]

Which Ports are getting shutdown? The ERS 8600 or the ES 470 Side?

Have you checked the logs to see if that helps. It sounds like you have some type of protectionism mechanism triggering.

[JJ]

My ERS8600 ports is getting shut down once i connect my 470 to my 8600 which is configured in VRRP.

[Jon Hurtt]

My ERS8600 ports is getting shut down once i connect my 470 to my 8600 which is configured in VRRP.

Have you checked the logs on the ERS 8600 to see if that can tell you what is happening...

[JJ]

in logs its showing due to heavy broadcast and cpu utilization and it shuts both the uplink port from both l3 switch, but i have not connected any system on that l2 switch.

[Jon Hurtt]

Sounds like you are creating a Layer 2 Loop somewhere and CP-Limit (Control Plane Limiting) is killing the port. I am bit confused on your Network Topology by your description.  Are you using any Link Aggregation Protocols (LACP or MLT/SMLT) to connect the Layer 2 Switch (ES 470) to the Layer 3 Switches?

Maybe post a network diagram and we can help you configure it correctly.

[JJ]

Hi, attached is the rough look alike diagram which i am trying now. i have two l3  connected to l2 switch and configured VRRP. and am not using any MLT/ SMLT i want to configure MLT but am little bit doubt with  mlt configuration and i dont want that it should create any loop so still not tried that..

[Jon Hurtt]

Hi, attached is the rough look alike diagram which i am trying now. i have two l3  connected to l2 switch and configured VRRP. and am not using any MLT/ SMLT i want to configure MLT but am little bit doubt with  mlt configuration and i dont want that it should create any loop so still not tried that..

Are the Two ERS 8600 connected to each other or share a common Layer 2 Network on another interface?

[JJ]

Both the ERS 8600 is not connected to each other directly they are connected via L2 switch.

[Michael McNamara]

As Jon mentions you probably have a loop somewhere in your topology (you just don't know it).

I would start by examining the topology tables of your switches and see if there are any connections that shouldn't be there.

http://blog.michaelfmcnamara.com/2008/12/nortel-discovery-protocol/

If you want to post a "show tech" from each switch I'll be happy to review them.

Cheers!

[JJ]

am getting logs """"""due to excessive control frames multicast""""""

[Michael McNamara]

As both Jon and I mentioned... this is because you have a loop in your network. You can't operate a network with a loop, you need to clear the loop which can either be a physically cabling error or a configuration error.

http://en.wikipedia.org/wiki/Switching_loop

Good Luck!

[JJ]

Thanks friends for your replies,
Yes its the issue with l2 loop but the reason am keep on posting here question is that, i have just connect my 2 8600 switch to 470  switch on VRRP mode, so what all configuration i am missing here which is the reason for loop creation, and another i am trying to have a redundant network and in Cisco its not so difficult and in nortel am just scratching my head cuz what i want is redundancy between switches..so pls let me know what will be better for me VRRP or any other....

 

[Jon Hurtt]

JJ,

We are here to help you, but you have to tell us what you are looking to do... It seemed you were having problems when connecting a ES 470 to two ERS 8600s, Did you successfully establish a connection between the two devices yet?

Based on your information it is evident that CP-Limit is disabling the port due to excessive multicast packets...

Are you are under the impression that a faulty configuration of VRRP is causing your loop? If so can you establish the connection without VRRP configured?

If you can establish a connection without the VRRP Configuration on either ERS 8600 then we can start to take a look at your VRRP Configuration to see if that is where the problem lies.

But first you must ensure that when connecting the ES 470 to both ERS 8600s you can establish a solid connection (This will help pinpoint the problem)

Hope this helps...

[Dominik]

Hi JJ,

a network Loop is a L2 problem. VRRP is a redundancy protocol taht works on L3.
You have to investigate your L2 topology. How are your devices connected to each other, do you use link aggregation, Spanning Tree, are SMLTs on yor switchcluster correct configured.....

In Cisco speech you can do L2 redundancy active/passive with STP. This is with Avaya identically.
To use active/active redundancy @ L2 in the Cisco speech you use VSS, in the Avaya world you do that with a design called Switch Cluster wich uses the features IST/SMLT to
built active / active L2 redundancy.

So do investigate your L2 topology, check the links, check your STP config and the link aggregation on your devices, this will help you to find the Loop in your network.

Good Luck