topic Re: Roaming between different models in Wireless

Roaming between different models

Moudar — Thu, 15 Dec 2022 12:20:06 GMT

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.

Re: Roaming between different models

b.winter — Thu, 15 Dec 2022 15:49:58 GMT

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

Re: Roaming between different models

Leo Laohoo — Thu, 15 Dec 2022 22:20:01 GMT

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.

Re: Roaming between different models

Haydn Andrews — Thu, 15 Dec 2022 22:20:06 GMT

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

Re: Roaming between different models

Moudar — Fri, 16 Dec 2022 07:55:25 GMT

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

Re: Roaming between different models

JPavonM — Fri, 16 Dec 2022 11:14:17 GMT

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)

Re: Roaming between different models

Leo Laohoo — Fri, 16 Dec 2022 12:46:45 GMT

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

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).

Re: Roaming between different models

Rich R — Fri, 16 Dec 2022 15:07:28 GMT

What model of WLC?
What version of software?

Re: Roaming between different models

Moudar — Fri, 16 Dec 2022 15:51:26 GMT

WLC 5520

Software: 8.10.181.3 upgrading to 8.10.182 is planned in January

Re: Roaming between different models

Moudar — Fri, 16 Dec 2022 15:59:53 GMT

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!

Re: Roaming between different models

Rich R — Fri, 16 Dec 2022 18:41:54 GMT

Ok well at least that is fairly up to date but you should be planning for upgrade to 8.10.183.0 now, not 8.10.182.0.

8.10.181.0 and 8.10.182.0 have been deferred:
https://www.cisco.com/web/software/DefTracker/280775080/DT/ac107255.html

This means if you have any problems with the deferred software TAC will just tell you to upgrade - it's essentially regarded as unsupported.

Re: Roaming between different models

Leo Laohoo — Fri, 16 Dec 2022 22:15:30 GMT

CSCwa31596

Re: Roaming between different models

Moudar — Sat, 17 Dec 2022 08:26:32 GMT

CSCwa31596

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

Re: Roaming between different models

Leo Laohoo — Sat, 17 Dec 2022 09:21:53 GMT

Then look at CSCwb80959.

Re: Roaming between different models

Rich R — Sat, 17 Dec 2022 11:13:51 GMT

> 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.

Re: Roaming between different models

Scott Fella — Sat, 17 Dec 2022 17:57:41 GMT

Reading through this thread, you now have ideas of what others would do. You already have an issue when you introduced a mix of ap models on the same floor, so the only real fix for that is when you migrate to all 2800's as an example. Have I mixed models in my environments, sure I have, but it is a whole floor or an area where roaming between the two does not happen. Any migration I do, is really for a complete upgrade, when I introduce a new access point model, its because the other is probably EOS or I recently upgraded those less than a few years ago.

Did you think of maybe migration one site first so you are not mixing models? You could always move the 2800's to one site and then replace them with the older ap's you took out.

I know this might not be helpful, but trying to give you some options before the experience gets bad and complaints go up the chain. Since this was something you implemented, saying, "well we shouldn't of mixed models" will not go well with management. You need to figure out your next steps, which might just be finding the old ap's and putting them back up. Waiting to upgrade is just extending the pain the users have to deal with and when you upgrade and that doesn't fix the issue, what will your response be to management?

Re: Roaming between different models

Moudar — Tue, 20 Dec 2022 15:44:49 GMT

@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!!

Re: Roaming between different models

JPavonM — Tue, 20 Dec 2022 16:03:19 GMT

Yes that could happen if the device has associated using 802.11ax protocol.

As part of the device association to a BSSID, the device sends an association request informang about its capabilities that are selected betweeen those in the beacon from the AP (or probe responses), and the AP sends an association response with the same.

Within that information which is shared, the devices inform about HT Capabilities, VHT Capabilities, HE Capabilities, Extended Capabilities between others (see "MLME-ASSOCIATE.join" and "MLME-ASSOCIATE.request" in 802.11 standard and 802.11ax amendment), and all that information must much to create an association. As the device coming from a WiFi6 AP has negotiated all that paramenters, the new connection to a WiFi5 AP must be also negotiated as none HE features exist anymore there.

But I'm still doing some testing when this is a WiFi5 device which roams from WiFi6 AP to WiFi5 AP, as all paramenters that are negotiatedare the same so it would be up to the logic inside the device's driver if they need to perform a full asociation, or re-associate as part of a seamless roaming.

Re: Roaming between different models

Scott Fella — Tue, 20 Dec 2022 16:08:09 GMT

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.