Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

design issue from 2 - MDS9124 switches to 4

I currently have 1 switch at our two buildings connected via dark fiber. They use one port for ISL between the two sites. I now need to add an additional switch at each site into the same fabric.

I think it would make sense to connect say, port 1 from the top switch to the bottom one. And I currently use port 24 for the ISL on the original switch I would like to do this for the new switch as well, this would basically make a ring topology (which I'm not sure if it would work correctly) ideally this would allow the traffic to flow either way.

I was reading about ISL trunking would this work or be appropriate for this? Any direction/help is appreciated as well as any info on how to connect the switches together.

New Member

Re: design issue from 2 - MDS9124 switches to 4

Attached is an image of what I am thinking. Also this is redundant, as I have a mirror of this setup for failover, etc..


Re: design issue from 2 - MDS9124 switches to 4

Hi there,

This is not generally a good idea to setup fibre channel networks into a mesh topology.

Mesh networks do not scale beyond the setup you have described.

Core/Edge is the best type of design to use as it can scale to thousands of ports and is easy to upgrade :)

Don't forget to have two logical or physical fabrics configured!!!


New Member

Re: design issue from 2 - MDS9124 switches to 4

Take a look at the JPG I have two seperate fabrics the top 2 switches are one fabric, the bottom two are another fabric which are stretched from the rack on the left to the one on the right.

While just looking at the bottom fabric (the bottom two switches on both racks)

Currently the diagram has one ISL I would like to make it an 8gb connection which I'm assuming I'll need to do a ISL trunk I am assuming from your last comment that I would use ports 23 & 24 on the top switch to do the ISL trunk. or would I use port 24 on the top and bottom switch to make the ISL trunk?

And any other comments/suggestions?

Also I am currently running 3.1 release is it worth going to the nxos 4.0 or later?

New Member

Re: design issue from 2 - MDS9124 switches to 4

I would upgrade to SAN-OS 3.3(2) as soon as possible. Please read the following Field Notice that appears will impact your environment.

Field Notice: FN - 63178 - MDS Fabric and Blade Switches May Reload After 497 Days of Uptime