9800CL Controller with IPv6 and Smart licensing strange behaviour

[oguarisco]

Dear all,

we are running a controller 9800-CL with Release 17.3 configured both for IPv4 and IPv6 on its interfaces and also for naming resolution.

The controller was registered with the Smart Account/Licensing but lately as soon we've added APs the license usage was in pending with HTTP communication error... pinging with IP Address or naming was fine .

wlan#ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 3/7/14 ms
wlan#ping tools.cisco.com
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 173.37.145.8, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 163/163/164 ms

But when I tried https connection to tools.cisco.com 443 I've noted that DNS resolution was done each time with IPv6

wlan#telnet tools.cisco.com 443
Trying 2001:420:1101:5::A, 443 ...
% Destination unreachable; gateway or host down

Removing IPv6 on the interface has solved the problem...

How can I force on IOS to use always IPv4 naming resolution since I'm obliged to keep both v4 and v6?

Thanks a lot for the support

BR

Omar

[marce1000 · Accepted solution]

                   - FYI : https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvc62532

   M.

[oguarisco]

Hello,

thank for the link

I've Release 17.3 and it should not be impacted but is quite similar

I will definitively have a look to add a static entry and see what's happen

BR

Omar

[Arshad Safrulla · Accepted solution]

If you do not have HA, consider configuring SLR.

https://www.cisco.com/c/dam/en/us/td/docs/wireless/controller/9800/tech-notes/c9800_sl_slr_dg.pdf

This is completely offline, and no need to expose the WLC interfaces towards internet. Another option is you can consider deploying a CSSM on-prem. I find smart licensing is always a challenge when the SSM cloud is configured.

Also note that even if you have HA redundant controllers and you still can deploy licenses only in the Primary WLC and leave the secondary WLC with eval licenses as 9800 still doesn't enforce the licenses. Only catch is when standby becomes primary it will throw out some warning syslog messages which you can easily ignore. I find peace at configuring SLR for my customers as I don't have to go through all these issues.

[oguarisco]

hello Arshadsaf,

thnx for the feedback... but since there is only a cisco Controller the best and easiest way is direct communication...

BR

Omar

[oguarisco]

Hello to all,

thanks for the excellent feedabck...

It took me a while to login to the AP because factory credentials are not the one mentioned in the document...

I was able to connect to AP with credentials cisco/Cisco and not admin/Cisco123