Trunking and Ether Channel

[Anthony Filice]

Scenerio- I have 2 switches that are connected to a SAN (for redundancy) I have a trunk between the two Switches and standard access ports connected to the SAN's NIC. What I want to do if possible- Combine 2 of the ports on each switch using etherchannel for Switch to Switch communication and leave the access ports alone. I should mention that Access ports are vlan 300 the Trunk port has a native Vlan of 300, Am I creating a packet storm if I do this? Any suggestions?

[ALIAOF_]

I have the same setup on one of my switch I have that switch connected to the main core switch via port channel (two ports) and then I have 4 access ports channeled together and connected to the SAN.

I am curious what is leading you to believe that this might cause the packet storm?

[Anthony Filice]

I have my SAN switches connected to the main switch via a management vlan only. I was thinking I may need to prune out the management vlan from the trunk between the two SAN switches to keep that from causing my management vlan from flapping. does this make sense?

[ALIAOF_]

So you have something like this setup:

SW1 --> SAN NIC1 (Access Port)

| --> Trunk Port

SW2 --> SAN NIC2 (Access Port)

Now you want to accomplish this:

                 --------------------|>   SW1 --> SAN NIC1 (Access Port)

Core Switch                         || --> Port Channel (2 trunk ports)

                --------------------- |>  SW2 --> SAN NIC2 (Access Port)

So you mean that creating a port channel can cause a spanning tree loop?  Do you have the priority setup on your core switch by any chance or is everything is default?  For instance on my main switch I have setup the priority for it to be the root bridge.

[Anthony Filice]

I have priority set up on my main switch for the management vlan - which has mulitple links, and is working well.  I guess I was concerned if adding etherchannel to trunk ports would cause any flapping by other ports not participating in that group