Optimal Settings for Wireless Roaming

[DanielBHSNIT]

We have a high density environment where professionals are moving between their areas and other areas to meet with clients and it seems the computers do not tolerate moving between the access points very well (some of our LOB apps drop connection).  I'm wondering what are some of your best practices or settings that are optimal?  

We have a combination of MR36, MR44, and MR56 access points.  Client balancing is turned off.

Thanks and looking forward to your input and insight.

[DarrenOC]

Hi @DanielBHSNIT , quick one, are your SSID's DHCP configured for Bridged or Layer 3 roaming?  If the SSID's aren't spread across different Layer 3 subnets then leave at Bridged.

[DanielBHSNIT]

The SSID's are configured for Meraki DHCP.

[UKDanJones]

This will be why then… in that mode each new AP will give the client a new IP address. Create a guest VLAN and use that instead. That way they’ll keep the same IP and do a proper roam rather than a dissociation and re-association,

[RLNG]

Is this how it works? Every time a client roams to a new AP the whole DHCP process restarts and the new AP will provide a new IP address? 

[alemabrahao]

Check the documentation.

https://documentation.meraki.com/MR/Wi-Fi_Basics_and_Best_Practices/Channel_Planning_Best_Practices

https://documentation.meraki.com/Architectures_and_Best_Practices/Cisco_Meraki_Best_Practice_Design/...

[UKDanJones]

Config can’t fix an incorrect design… I’d suggest getting a professional in to check your design/config and report back to you. 

[DarrenOC]

🙂 - knew you wouldn't be too far behind on this one.

[DanielBHSNIT]

Correct it can't, not usually, but other than different models of AP, what else could be incorrect?  I've had two vendors look at my configuration and design and the Cisco vendor who sold me this stuff in the first place didn't mention that the AP model should be identical throughout your building... (that kind of irks me they didn't)

[DarrenOC]

Did they perform any form of survey and underwrite a design?

[DanielBHSNIT]

They didn't.  This wasn't brand new deployment but a replacement of Cisco SAP1602's.  I did state in the OP that across the organization we have a mix of AP models but in its the same model in each building; in case the one building with the issue, it is all MR36's.

[UKDanJones]

Time to find a new Cisco VAR… doesn’t sound like they’re adding much value…

[DarrenOC]

a wifi purist may also state that roaming between different AP models isn't the ideal scenario either.  Whilst you're using the same generation of AP (next gen & wifi 6) the transmitters are different - 4x4:4 and 2x2:2 cannot exchange tables.

[UKDanJones]

Clients will also prefer newer PHYs and APs with more spatial streams. 

[PhilipDAth]

The #1 issue I find is the WiFi driver - especially Intel WiFi drivers.

Make sure you install the latest WiFi driver from the manufacturer of the WiFi chipset (rather than the OEM of the notebook).

I've had lots of issues with customers that use Microsoft Surface Pros.  Microsoft keeps using the cheapest sh*tiest WiFi chipsets available.  Hopefully, you are not in this camp, as the issue is not likely resolvable without changing to a different brand of notebook.

The #2 biggest issue I run into is the WiFi chipset going into powersave mode.  Not all WiFi chipsets expose these settings in the GUI.  You can disable WiFi power saving with the two below commands.  I primarily run into this with Intel WiFi NICs.

powercfg /SETDCVALUEINDEX SCHEME_CURRENT 19cbb8fa-5279-450e-9fac-8a3d5fedd0c1 12bbebe6-58d6-4636-95bb-3217ef867c1a 0
powercfg /SETACVALUEINDEX SCHEME_CURRENT 19cbb8fa-5279-450e-9fac-8a3d5fedd0c1 12bbebe6-58d6-4636-95bb-3217ef867c1a 0

#3

If this is a WPA2-Enterprise deployment, and you are using Microsoft NPS, make sure "Fast Roaming" is enabled in

both NPS AND on the client.  Without this clients have to go through a 100% full authentication everytime.  This often creates "micro" outages when roaming.

Maybe #4 is you still having 2.4Ghz enabled.  Turn it off.  It causes so many issues, especially in a high-density environment.

Maybe #5 you haven't configured only to use 20Mhz channels.  Do not try and use anything wider.

Maybe #6 - your power levels are too high on the APs, discouraging clients from roaming.  For a high-density deployment, I would use settings like this:

I just learned you can't use the word sh*t in a post.  That's my learning for today.

[Paccers]

Little high on the TxPower @PhilipDAth given Meraki's Tx value is from the radio and not EIRP?

[UKDanJones]

My max Tx on meraki is never normally higher than 14 dBm. 

I'd also suggest 24 Mbps as your min basic rate if it's an open office environment

[DanielBHSNIT]

We've been 99% Dell shop running Latitudes with Intel WiFi.  One side of the house is imaged using MDT and I do update the driver packs on regular intervals.  The other half the house is Microsoft Intune, and I'm not sure how it does its driver management other than when it does the initial user set-up at login the first time.

[DanielBHSNIT]

I wanted to thank everyone for the replies.  We've gone through and implemented what we could.

[DanielBHSNIT]

This post is a little bit stale, if anyone is still subscribed to it, does Mandatory DHCP have any adverse impact on roaming?

[alemabrahao]

No, it basically prevents it from being possible to connect to the network if it has a fixed IP.