Migration from 5508 to 9800-CL chromebook considerations

JH_1155 · ‎09-16-2023

First post. Be gentle Trusted vendor migrated our 5508 to a 9800-CL over the summer. We have a mixture of Windows and chrome OS with a 100+ IOS devices. Ipads. Smooth sailing and all was well when less people were in the building.

The Windows side of this migration has been fine. Even with the majority of end users back in the building. The chrome devices have not been fine. Slow loading, some disconnects at random intervals. All chromebooks. Chromeboxes on a different ssid are behaving the same way. Windows clients are 802.1x and chrome clients are wpa2/psk. Controller is running 17.9.3.

I inherited the 5508 and it was something of a delicate genius as far as where it ended up and it's performance vs. how it initially rolled out years ago. It ran great these last 4-5 years if not more. I am struggling with trying to get the 9800 up to speed. I'm not sure what the magic was in that 5508 config that had things running so smooth. QoS was setupin the controller but not on the switch end, so I have no idea how impactful that was in retrospect. We have a APs in each classroom. I have been looking at high density client settings but not sure our environment warrants this just yet. I have also tweaked the session timeout settings to larger values but I feel like I am poking around in the dark a bit.

Are there any best practices for chrome OS specific configuration on the 9800? Thanks for any suggestions you might have on the subject.

ammahend · ‎09-16-2023

to start with run the basic KPI check on wireless intra, ensure endpoint drivers are up to date. optionally you can run config analyser for both 5508 and 9800 and compare I know it’s not an apple to Apple comparison but maybe you can find some obvious pointers you missed out?

https://cway.cisco.com/wireless-config-analyzer/

https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/217738-monitor-catalyst-9800-kpis-key-performa.html

-hope this helps-

JH_1155 · ‎09-16-2023

Thank you sir! Exported the config and ran the tool. When I have time this weekend; I will take a deeper look at this and see what needs changed on my end.

Leo Laohoo · ‎09-16-2023

@JH_1155 wrote:
The chrome devices have not been fine. Slow loading, some disconnects at random intervals. All chromebooks. Chromeboxes on a different ssid are behaving the same way. Windows clients are 802.1x and chrome clients are wpa2/psk.

This is not a wireless issue. This is an issue with the Intel-based wireless NIC.

We have a ticket with Google who admitted this behaviour. The wireless dropouts are worse when the ChromeBooks are 802.1x authenticated but the dropouts are not so severe if the ChromeBooks are using PSK.

We have been asking Google to share their Intel trouble ticket but they are unwilling to do so.

JH_1155 · ‎09-17-2023

Ugh. That is terrible. Have you found anything that helps mitigate this to any degree? I am thinking about hardwiring the chomeboxes for now. It doesn't alleviate the problem for the student device POV; but it at least puts it out of the mind of staff who are the primary users of the chromeboxes.

Leo Laohoo · ‎09-17-2023

Use PSK and the number dropout events are minimized.

JH_1155 · ‎09-17-2023

Have you noticed slower connection speeds and overall sluggishness after migration? That's another thing beyond dropped connections. I need to dig into that wlc config analysis this week and see if I am missing something on that front as well.

Leo Laohoo · ‎09-17-2023

@JH_1155 wrote:
Have you noticed slower connection speeds and overall sluggishness after migration?

I never, ever, tell users I am migrating them -- Placebo effect.

JH_1155 · ‎09-22-2023

Little follow up. Started a case earlier this week with Cisco on this.Thinking it was essentially all the chromebooks fault Turns out when the vendor did the migration; they setup equivalent Policy Tags from the 5508 to put the APs in but did not set up site tags and are just using the default site tag. Which sounds like it's causing excessive roaming requests from what the Cisco rep is telling me.

We have five buildings and two of the five are reporting issues with the chrome devices. I am going to setup a site tag for each building and apply that tag to all of the aps in those buildings first and see how it goes. They aren't large facilities so I am not sure if it's going to be worth drilling down for tags for specific hallways/regions of each building or if a per building designation will be enough. We'll see.

Leo Laohoo · ‎09-22-2023

@JH_1155 wrote:
they setup equivalent Policy Tags from the 5508 to put the APs in but did not set up site tags and are just using the default site tag.

Exactly how many APs are in that default site tag?

Cisco Best Practice says up to 500 APs per site tag.