Roaming issues


Userlevel 1
C5210 controllers with 9.21.10.5 and 3605/3610 APs. Does anyone else in a school district setting have roaming issues and ways to improve it? We have principals that use iObservation tool on their Macbooks and roam to different classrooms. They say they can connect, get kicked off, can't get back on, get dropped...Is there such a thing as seamless roaming? I tell them to reboot machine and turn wifi on/off.

14 replies

Userlevel 2
Macs I have seen are notorious for "sticking" to an access point. This is more of a client issue and you may need to go to each client and adjust the roaming aggressiveness.
However, how high are your radios turned up? Are you trying to cover as much area as possible with your Access points? It may be as simple as lowering your power. Also, try and force the clients to use 5Ghz and turn your 2.4 way down. This will compartmentalize your signal a bit better.
Userlevel 2
Rich Upshaw wrote:

Macs I have seen are notorious for "sticking" to an access point. This is more of a client issue and you may need to go to each client and adjust the roaming aggressiveness.
However, how high are your radios turned up? Are you trying to cover as much area as possible with your Access points? It may be as simple as lowering your power. Also, try and force the clients to use 5Ghz and turn your 2.4 way down. This will compartmentalize your signal a bit better.

Think of the client being attached to the AP like a rubber band. Go too far away and the rubber band will break however it gets weaker as you go further away.
Something I just thought of too, what is your minimum basic rate set at on your ap's? 6mbps? if so, it may help to up it to 12mbps.
Userlevel 1
Rich Upshaw wrote:

Macs I have seen are notorious for "sticking" to an access point. This is more of a client issue and you may need to go to each client and adjust the roaming aggressiveness.
However, how high are your radios turned up? Are you trying to cover as much area as possible with your Access points? It may be as simple as lowering your power. Also, try and force the clients to use 5Ghz and turn your 2.4 way down. This will compartmentalize your signal a bit better.

But if I up it to 12, won't the cell size get smaller, and the users will need to be closer to the APs.
Userlevel 2
Rich Upshaw wrote:

Macs I have seen are notorious for "sticking" to an access point. This is more of a client issue and you may need to go to each client and adjust the roaming aggressiveness.
However, how high are your radios turned up? Are you trying to cover as much area as possible with your Access points? It may be as simple as lowering your power. Also, try and force the clients to use 5Ghz and turn your 2.4 way down. This will compartmentalize your signal a bit better.

Yes, and that's the point. If you're having roaming issues, the bottom line is that the signal strength that your client is receiving is still strong enough to hang onto the AP it's associated with, even if it's down the hall.
Less is more here.
How far are your AP's spaced apart?
What is your max power level set to on your AP's? Particularly your 2.4 radio?
Userlevel 1
Rich Upshaw wrote:

Macs I have seen are notorious for "sticking" to an access point. This is more of a client issue and you may need to go to each client and adjust the roaming aggressiveness.
However, how high are your radios turned up? Are you trying to cover as much area as possible with your Access points? It may be as simple as lowering your power. Also, try and force the clients to use 5Ghz and turn your 2.4 way down. This will compartmentalize your signal a bit better.

almost every classroom and in the halls. We don't have a professional install of the devices. There were just plugged in, wherever I could find a working data drop. I'm sure some of the issue is AP placement.



Userlevel 2
Rich Upshaw wrote:

Macs I have seen are notorious for "sticking" to an access point. This is more of a client issue and you may need to go to each client and adjust the roaming aggressiveness.
However, how high are your radios turned up? Are you trying to cover as much area as possible with your Access points? It may be as simple as lowering your power. Also, try and force the clients to use 5Ghz and turn your 2.4 way down. This will compartmentalize your signal a bit better.

That looks good for power levels on the surface. What do the advanced setting look like? How do the rest of them look, similar? Are your 2.4 radios turned on for every access point or have you limited that down?
I'm assuming your classrooms are pretty normal sized so even if your AP placement isn't perfect, given the amount of AP's you have, it sounds like there is a lot of flexibility to tune your radios the way you want them to.

Back to your cell size question: Given that you have an AP in the halls and in every classroom, you want to get it as small as you possibly can. You most likely have a lot of bleed-over into adjacent rooms.
Userlevel 1
Rich Upshaw wrote:

Macs I have seen are notorious for "sticking" to an access point. This is more of a client issue and you may need to go to each client and adjust the roaming aggressiveness.
However, how high are your radios turned up? Are you trying to cover as much area as possible with your Access points? It may be as simple as lowering your power. Also, try and force the clients to use 5Ghz and turn your 2.4 way down. This will compartmentalize your signal a bit better.




Maybe I should remove the hallway APs and put them in the classrooms.
Userlevel 2
Rich Upshaw wrote:

Macs I have seen are notorious for "sticking" to an access point. This is more of a client issue and you may need to go to each client and adjust the roaming aggressiveness.
However, how high are your radios turned up? Are you trying to cover as much area as possible with your Access points? It may be as simple as lowering your power. Also, try and force the clients to use 5Ghz and turn your 2.4 way down. This will compartmentalize your signal a bit better.

Without knowing what your floorplan looks like, I'm just going to take a stab at a recommendation:
Turn off 2.4 in all the classrooms and turn off 5Ghz in the hallways. Let the AP's in the hallways take care of the Overlay (2.4) and try to make each classroom a compartment with a different 5Ghz channel. Not sure if you have an iPhone or an Android, but I use WiFi analyzer on Android to get a quick reading of what my spectrum looks like in a given location. If you can get a strong signal strength from the AP in the next classroom over, turn the radio down. This will make a more natural roaming environment.
Userlevel 2
I would do some channel analysis like Rich suggested if you have not already to see how many AP's you can see/hear from a given classroom. You have your channel selection to Auto which is probably going to lead to having multiple AP's on the same channel, at least from my experience (depending on how dense your deployment is ).

Apple devices are usually good at using 5ghz if they are somewhat current. You can look at increasing the Min. Basic Rate, especially on radio 1. Unless you have a really sparse AP deployment, you want higher than 6 Mbps from my experience for radio 1. This *can* help with roaming.

If you have floor plans, go through your AP's, mark them on the floor plans,note the channel each is running on and the last six of one of the BSSID's for each AP. Without even doing any onsite testing, if you look at the floor plan and have AP's next to each other on the same channel, you are going to have all kinds of issues like you are describing. You can use the plans as a guide to setting the channels manually which is pretty easy to do using 20mhz wide channels on radio 1 once you get an idea of signal penetration. Not sure of the size of buildings you are dealing with, so maybe this isn't practical, but I have done this and refer to them regularly. Another option would be putting the maps into oneview (if you have that) to get a look at the channel layout.

As suggested though, you need something to give you a look at what your dealing with. Other suggestions include AirPort Utility, Wifi Explorer or inssider. All depends on what kind of device you have.
Userlevel 4
Hi Laura,

Please find the below KB for general details about roaming issue and what needs to be checked.

https://gtacknowledge.extremenetworks.com/articles/Q_A/why-do-my-wireless-clients-not-roam-properly

Check this issue step by step , how many clients are affected and how long ?

If you change anything from AP properties and save the settings it might affect live network users .

So trace the issue where it is and confirm first before changing anything on EWC network.

Thanks,
Suresh.B
Userlevel 4
Hi Laura,

Can we check whether the clients connects to the nearer AP's or the far away AP's while roaming. If they are connecting to the far away AP's they will have intermittent connection.

You can check in Reports -> Clients -> VNS -> Select the SSID and filter it with MAC address to check the AP on which the client connected.

Regards,
Nathiya M
Hi Laura,

If you are interested, I can have you remote into one of my sessions and explain what to look for in a live environment. Some of the numbers etc make more sense when you can equite it to an actual client that's connected.
Userlevel 1
"More the minimum basic rate in Basic Radio Settings better and faster is the Roaming"
Userlevel 4
Hi Laura,

In case you find its an issue with clients connecting to far away AP while roaming the below settings helps to address the issue.

https://gtacknowledge.extremenetworks.com/articles/Solution/Issues-with-clients-staying-with-an-Acce...

Regards,
Nathiya M

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