9800-CL Performance questions

[ALIAOF_]

I'm trying to get some feedback from users who may be using 9800-CL. Are you doing FlexConnect or Local Mode?

If you are doing Local Mode any performance related issues and/or any other caveats using the virutal environment?

I see FlexConnect as an option and not let data traffic hit the controller to avoid any issues. Roaming between different groups can be a caveat but if it's just WPA2-PSK network it shouldn't be a huge concern.

Would love to hear some thoughts around that.

[Flavio Miranda]

Hi

 Usually the WLC is not the concern. Way before the WLC get performance problem, you will get problem with Air time utilization on the Air interface of the Access Point.

 The wifi part is where problem reside or at least, where problem start first.  Usually, WLC handle traffic pretty well whether local or flexconnect.  That´s why you have a limit of access point to join.

 If you are strugling with flexconnect to avoid send traffic to the WLC, I can asure you it is not necessary. Unless, of course, you network infrastructure is really bad but than, the problem is not the WLC also.

[ALIAOF_]

I am talking about the 9800-CL vWLC not the appliance.

[ammahend]

Agree with Flavio, there are lot of non WLC related issues that can cause performance issue. 9800-CL is highly scalable, I usually prefer it for small deployments for large deployments I prefer Appliance if it’s not mandatory to go with CL version, e.g 9800-80 supporting 6000AP can have a 100gig uplink, compare that to your VM ? Plus I am not a big fan of adding another troubleshooting piece (vendor) into mix specially for critical infrastructure if I have choice, but that’s just me. 

Other than that their are standard best practices for choosing your deployment modes, they apply to both VM and Alliance, here is a good starting point

https://www.cisco.com/c/en/us/td/docs/solutions/CVD/Campus/cisco-campus-lan-wlan-design-guide.html

[Arshad Safrulla · Accepted solution]

9800 doesn't support Hyperthreading. By the time and cost you deploy a dedicated ESXi or hypervisor for the WLC's you can easily afford hardware boxes

Selecting Flex or Local mode purely depends on the complete design and the AP distribution (across sites etc)

It is strongly recommended that you use certain NIC cards by Intel to achieve higher throughput if the AP's are in local mode. Otherwise you will run in to throughput issues. Also make sure that you use the correct OVA template as per your requirements.

Hypervisor support dependency. 

Flexconnect mode restricts you not to exceed 100AP's per site tag. (Not restricted by WLC configuration but a best practice)