Interconnecting Nexus 5548's via Dual 2960S

[jburk]

I am trying to interconnect a pair of Nexus 5548 at adjacent sites, using 2 2960-S switches at each site, the reason being that the Multimode Fiber between the sites will only support 100mb and I need this up while I finish having SMF laid.

I have attached a diagram, just debating whether to use etherchannel or vPC - would like to hear some opinions...

Assume the interconnect between the 5548's needs to be 802.1q trunk

[Reza Sharifi]

You don't have to  have single mode fiber to do Gig or 10Gig.  Multimode fiber supports 100Mb,  1Gig, 10Gig etc...

The difference between the 2 fiber type is the distance they support not the speed.

HTH

[jburk]

Yes, that is why I stated that the fiber will only support 100mb, because of the distance. Not because of the Fiber Spec.

I was looking for input on the configuration for the etherchannel

[Leo Laohoo]

I am trying to interconnect a pair of Nexus 5548 at adjacent sites, using 2 2960-S switches at each site

1.  In each site, the 2960S are stacked together, right?

2.  I'm not sure if you want to push 10 Gbps on a 2960S as the backplane alone is just 10 Gbps.  You want to push 10 Gbps and stack?  Think of the 3750X instead.

the sites will only support 100mb and I need this up while I finish having SMF laid.

I agree with Reza in this statement.  Can you please elaborate?

I have attached a diagram, just debating whether to use etherchannel or vPC

Compared to what?  Etherchannel from the Catalyst switch to the Nexus and vPC from the Nexus to the Catalyst is good.

[jburk]

The switches are not stacked, just want to connect to the 2960S as temporary media converters to light up the long MMF run that wont support over 100mb

[n_schloemer]

I am actually in the middle of a data center conversion, in which we have just installed dual 5548UP's and they are currently trunking to stacked 3750's.  In my case since they were stacked I configured a vPC on the 5K side and a Port-channel on the 3750's side.  Since your's are not stacked I would suggest not configuring the vPC links and instead configuring typical ether-channel.  If it were me I would treat the 5K's as if they were just standalone 2960's.  The whole concept behind vPC was to prevent the blocking of source ports on seperate switches because of spanning-tree.  In your case that is not coming into play; if you had 2 5K's into a single 2960 that would have a configured port -channel then i would use a vPC.  If you want to control which port on the 2960's is not blocked use port priority with spanning tree and you will keep the quickest route to distribution or core layers (not sure what the rest of your topology looks like) while also maintaining failover in the event the primary link fails.