Roaming between different models

[Moudar]

Have 2802 and 2702 at the same floor (only one floor). Should the roaming work or there are buggs somewhere?

The 2802 AP sends many logs as this one:

*** RSN ERROR: Received a data frame when no keys are plumbed

Someone here:

 https://community.cisco.com/t5/wireless/rsn-error-received-a-data-frame-when-no-keys-are-plumbed/td-p/4612689

said "I saw that every time they reported the issue with the "Connecting" status they were connected, but they weren't finishing the  roaming process between APs."

I have 2 locations with the same problem and with mixed environment 2702 and 2802. only 2802 have these logs.

Clients say that they loose connection very often when they come to a room that has 2802 and the room before has 2702 AP.

[b.winter]

I guess, you are in the wrong forum. Better post your question in the "Wireless - Mobility" forum: https://community.cisco.com/t5/wireless-mobility/ct-p/4931-wireless-mobility

[Leo Laohoo]

Roaming between "generations", like IOS-based x700 and Cheetah OS-based x800, is not recommended. 

The main reason is because the radio chipsets behave differently.  For instance, there are plenty of Bug IDs relating to the MARVEL chipset inside x800 (2800/3800/4800/1560/IW6300) that only affects this generation of APs.  

[Moudar]

What about roaming between 2802 and 9120 models? is it better to have these around each other? We have 3 different models (27, 28, 9120) at the same floor (school with Ipdas)! It sounds stupid but so it is. (The client had 5 pcs 2702 for years, 2 years ago the added 2 pcs 2802 and they did add another 9120 because we don't order 2802 any more )

You know we can't change everything! 2020 and 2021 all orders were 2802 which were added to the network, then we started order 9120

[Leo Laohoo]

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@Moudar wrote:
The client had 5 pcs 2702 for years

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My 3700 are >7 years old and the 5.0 Ghz will start to fail at around the 6 year mark. 

However, I would never make any roaming between generations.  Troubleshooting roaming or joining will be a nightmare.  x800 particularly is prone to dropping (if not randomly "blackholing) packets and several issues with MS Teams (I have seen 2 bug IDs related to MS Teams and 2800/3800/4800/1560/IW6300).

[Moudar]

What are these bug IDs? In my case when it comes to MS Teams so my advice to people is always use cable and that is because wifi is not good all the time, sometimes it works with no problem and sometimes it does not!

[Leo Laohoo]

CSCwa31596

[Moudar]

CSCwa31596 

is about 9130 AP model which i don't have, what i have is 2802 and 9120. Do these have any bug IDs?

[Leo Laohoo]

Then look at CSCwb80959.

[Rich R]

> CSCwa31596  is about 9130 AP model which i don't have, what i have is 2802 and 9120. Do these have any bug IDs?

Did you look at the affected products list on the bug? 
The description is often just what a customer first reported the problem with when a TAC case was opened.  Lazy TAC and dev engineers often don't bother to update the bugs with accurate descriptions and notes once they've fixed the bug and know the full details.  Generally speaking a bug in AP-COS code will affect all APs since the wave 2 (x8xx) APs because they're all running the same code - except where the bug is in platform/hardware specific code like drivers in which case it only affects the models with specific chipsets or drivers but this will usually be stated in the notes.

[Haydn Andrews]

I try an avoid having different model APs in a roaming area as have seen issues caused particularly around clients perfering the newer model AP over the older one

[JPavonM]

I would try to avoid mixing APs from different Wi-Fi generations as this could lead to disconnections when roaming from the most modern one (C9120) to the previous one (AP2802) if the end-user device is WiFi6 capable due to the fact that they will have to reassociatte to negotiate new capabilities (lower capabilities)

[Moudar]

@JPavonM you mean that if a client is roaming from wifi6 to wifi5 (or wifi5 to wifi6) it will disconnect for a second and reconnect (reassociate)?

We don't have many wifi6 clients just yet but for sure they will be more and more!!

[Scott Fella]

It's all about how you migrate.  I think folks seen this when 802.11n came out then 802.11ac, etc.  Newer devices prefer a protocol and then what you see are clients being sticky.  So as long as you know this, then you can better plan out how you migrate.  You can always look at client counts and see if you see more clients on newer access points or not.  You can also look at the device like a windows machine and see what devices they have roamed to.  I'm migrating from wifi5 to wifi6e and it will be a full replacement, no mix and match.  In larger environments, you have to plan that better and migrate areas at a time depending on how long it takes to replace all the access points during a downtime.

[Rich R]

What model of WLC?
What version of software?