Ever been confused on which software version your Cisco Controller should be running?

Guess what…you’re not alone.

This is a question that I get asked by customers and fellow engineers alike. I often feel like I’m ‘tuned in’ to the software versions that are available (and they’re are a plenty), but in all honesty my decisions on this matter are guided by the feedback of the community and Cisco.

Your first step in this decision is to determine what software limitations you have based on hardware. Not all Cisco Controllers can run the same software, and not all Access Points support certain versions. Add in PRIME/MSE/CMX/Converged Access, and confusion sets in quickly.

Luckily Cisco has a page dedicated to assisting you figuring out what you can use with the hardware your current infrastructure has, or future deployments will have.

Cisco Wireless Solutions Software Compatibility Matrix

Utilizing this guide, ask yourself some quick questions:

1. What model of Controller do I have?
   • What model of Controller do I plan to upgrade to?
2. What model Access Points do I currently have?
   • What model Access Points will I be upgrading to?
3. Do I have PRIME?
   • Is it a virtual install?
   • Is it a hardware version?
4. Do I have MSE…CMX…Converged Access?

Knowing some of the basics of your deployment should give you enough to be able to go down the checklist of the compatibility matrix and ensure you’re making the right decision.

Once you’ve figured out which software releases you can use, now you need to decide which version you want or need to use.

What’s that you say? You want the latest and greatest code you say? Well, slow down there old friend. I heard down at the local five and dime, that Cisco also has recommended versions for each software release.

TAC Recommended AireOS

The recommended AireOS are also highlighted in CCO via the star icons, and hovering over them will show that they are a suggested code that ties directly back to the TAC recommendations

Sometimes you’ll find out via the compatibility matrix that your choice is forced upon you. For example, if you have a 5520 controller, or maybe the newer 1830/1850 Access Points, you have no choice but to use the first generation code they support (8.1). This has a tendency to make the decisions easier, since they’re are far fewer options to choose from. Choosing the ‘older’ code version tends to be the safe choice in these scenarios (ie. 8.1 instead of 8.2 for a 5520).

As of the date of this post, I can’t see any reason to be running 8.2 in a production environment as there are no hardware restrictions forcing you on it. As for testing, well why the heck not!

Since the hardware is still relatively new, I personally consider 8.1 or 8.2 to be bleeding edge, and if you’re running a 2504/5508/WiSM2, I say stay away for now. Stick with the TAC recommended.

NOTICE

1. Choosing 8.1 or 8.2 will cut off any older Access Points you might have.
   • (1130/1240/1250/1520 series)
2. If you are still running 7.6.130.0, please be aware that 7.6 is deferred.
   • Cisco recommends upgrading to 8.0.121.0

Cisco also has something called the Cisco® AssureWave program, which is basically a code version that has been through much more rigorous and extensive testing to show that the software version in question has been validated to meet higher standards. Currently, the only option available is 7.4.121.0. This is indicated by the blue check mark ribbon icon next to the code version.

Finally, if you’re also looking for information regarding what Field Upgrade Software (FUS) image you should be running, choose the latest version available and do not upgrade it with the same version more than once or you will brick your controller. For further information on FUS, I’ll point you over towards Craig Schnarrs’ excellent blog post What’s all the FUS About?

Hopefully this post will assist you in your decision on what software version of Cisco WLC code you should run.

Enjoy!

-Nolan