topic Re: 9800 client IP acquiring delay in Wireless

9800 client IP acquiring delay

komiks — Tue, 19 Dec 2023 10:02:40 GMT

We are to migrate WLC from AireOS to 9800. but we are getting an issue on the delay the client is getting an IP.

The setup is WLC with dot1x authn and ISE posture.

the comparison is when using 9800, it takes 10seconds longer on the posture assessment and IP acquisition than using the aireos wlc. which is not acceptable with the client that's why we can't proceed with the migration.

Re: 9800 client IP acquiring delay

Mark Elsen — Tue, 19 Dec 2023 12:42:16 GMT

- Start with a checkup of the 9800 (current) configuration with the CLI command show tech wireless and feed the output into
Wireless Config Analyzer

- For DHCP client provisioning use these advices as being best practice(s) : https://www.cisco.com/c/en/us/products/collateral/wireless/catalyst-9800-series-wireless-controllers/guide-c07-743627.html#DHCPbridgingandDHCPrelay

- Debug clients according to https://logadvisor.cisco.com/logadvisor/wireless/9800/9800ClientConnectivity (correctedx2) , you can have client debugs , so called RadioActive Traces , analyzed with : https://cway.cisco.com/tools/WirelessDebugAnalyzer/

- Monitor overall client behavior and or check for improvement with commands mentioned in : https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/217738-monitor-catalyst-9800-kpis-key-performa.html#anc5

Re: 9800 client IP acquiring delay

MHM Cisco World — Tue, 19 Dec 2023 13:40:36 GMT

So in end the client auth or not?

Are you use dual dhcp subnet pool ?

MHM

Re: 9800 client IP acquiring delay

Rich R — Tue, 19 Dec 2023 15:22:45 GMT

What version of IOS-XE are you using on the 9800?
Hint: refer to TAC recommended link below.

Re: 9800 client IP acquiring delay

komiks — Wed, 20 Dec 2023 01:39:58 GMT

yes,the client authenticates, we are using the same dhcp server for different subnets.

Re: 9800 client IP acquiring delay

komiks — Wed, 20 Dec 2023 01:40:17 GMT

version is 17.9.4a

Re: 9800 client IP acquiring delay

Rich R — Wed, 20 Dec 2023 01:41:54 GMT

Ok that's a good start.
And have you done a radioactive trace on a client to understand what is causing that delay?

Re: 9800 client IP acquiring delay

komiks — Wed, 20 Dec 2023 06:24:20 GMT

right now what we do is to connect the client in a different AP. result is its faster compared to the other AP. but question is, they have the same firmware version and model, same tags and profile so what may be the cause why it's longer to connect on the other AP?

Re: 9800 client IP acquiring delay

komiks — Wed, 20 Dec 2023 06:58:38 GMT

not sure what to look exactly on teh RA trace regarding delay.

Re: 9800 client IP acquiring delay

Rich R — Wed, 20 Dec 2023 09:46:18 GMT

Then best to open a TAC case and let them work through it with you.