topic Re: Disable the use of IPV6 in cisco 9800-CL in Wireless

Disable the use of IPV6 in cisco 9800-CL

Chandan Singh — Mon, 06 Jan 2025 07:20:38 GMT

Is there a way we can disable the use or display of IPv6 in cisco WLC 9800-CL.

if anyone has idea why Ipv6 is also allocated to clients ,when not being used.

Re: Disable the use of IPV6 in cisco 9800-CL

MHM Cisco World — Mon, 06 Jan 2025 07:19:38 GMT

the VLAN SVI config in Core SW from there disable IPv6

MHM

Re: Disable the use of IPV6 in cisco 9800-CL

Chandan Singh — Mon, 06 Jan 2025 07:22:24 GMT

Can it be done from WLC end ?

Re: Disable the use of IPV6 in cisco 9800-CL

MHM Cisco World — Mon, 06 Jan 2025 07:32:17 GMT

If DHCP is run on core SW then it control the IPv6 assign to wifi client.

MHM

Re: Disable the use of IPV6 in cisco 9800-CL

Mark Elsen — Mon, 06 Jan 2025 07:50:21 GMT

- It will be off by default when not configured ; clients usually show default link local addresses , unrelated to the WLC,

Re: Disable the use of IPV6 in cisco 9800-CL

heysmirk03 — Mon, 06 Jan 2025 08:57:55 GMT

You say it's a flat network. Is the SVI you are managing the C9800 on the same VLAN as your SSID and clients are? I suspect the C9800 is consuming the IPv6 packets. Separate it out. Use a unique VLAN to manage the C9800, attach your SSID to a different VLAN and don't create an SVI on the C9800 for it, just create the L2 VLAN.

Re: Disable the use of IPV6 in cisco 9800-CL

Rich R — Mon, 06 Jan 2025 16:30:39 GMT

The only way to stop a client giving itself an IPv6 address is to disable IPv6 on the client.
The advice from the others already covers the other possibilities.

Re: Disable the use of IPV6 in cisco 9800-CL

Haydn Andrews — Mon, 06 Jan 2025 21:33:08 GMT

I think you will find the IPv6 addresses are link local (self assigned by the clients) do they all start with fe80?

If thats the case only way to disable it is to do it on the client

Re: Disable the use of IPV6 in cisco 9800-CL

lukaszdaczkowski — Wed, 22 Jan 2025 14:33:22 GMT

Hello Chandan

You can use this command:

conf t
no wireless ipv6 client

LAB-9800-1(config)#no wireless ipv6 ?
client Disable wireless client IPv6 traffic on Wireless controller
(centrally switched)
nd Configure wireless IPv6 ND parameters
ra Configure wireless IPv6 RA parameters

BR

Luke

Re: Disable the use of IPV6 in cisco 9800-CL

Paccers — Wed, 19 Feb 2025 07:53:28 GMT

Same problem being experienced for us with 9800-CLs in Azure. We migrated from AireOS where no IPv6 IPs were learned or being forwarded, we now have many clients showing with fe80 IPv6 addresses and they are also being passed on to firewalls via Framed-IPv6-Address value in RADIUS Accounting packets. We're using the same Flex w/ central auth & local switching setup as we did with AireOS and haven't changed anything on local switch SVIs, this has come about since 9800 migration.

@Chandan Singhdid you find a solution in the end?