Problem with NME-WLC connectivity to router

[Dennis Goh]

Hi Wireless gurus,

I've recently tried to demo the NME-WLC modules integrated to the Cisco 2921 router. However, I've bumped into an issue with the NME-WLC's connectivity to it's host router.

Initially, when I configured the router and the WLC, I did not have any problems with the connectivity, however, when I came back the next day, the setup wasn't working anymore.

Here is the configuration highlights:

I have the router sub-interface in1/0.3 configured with the IP 172.30.25.33 /27 tagged with the vlan 3 which is supposed to be the wireless user vlan.

I have another sub-interface g0/0.2 on the router configured with 172.30.25.1 /27 which is meant to be the management segment. I have used interface in1/0 with "ip unnumbered g0/0.2" to save a segment of IP in my environment.

I've configured the WLC's management IP to be 172.30.25.7 /27 and the ap-manager IP to be 172.30.25.8 /27.

I've configured 1 dynamic interface on the WLC which is vlan 3 tagged with the IP of 172.30.25.62 /27

Router is running version ipbasek9.SPA.150-1.M4 and WLC is running version 6.0.199.4.

Here is the issue:

I have no problems pinging from router to the WLC management IP and WLC AP-manager and vice versa. And I have no problems pinging from router to 172.30.25.62 (dynamic interface), however from the WLC, I could not ping to 172.30.25.33 (the interface IP with the same segment).

I also noticed that when I change the IP of the dynamic interface or change the vlan of the dynamic interface and change it back, the WLC is then able to ping the interface IP of the router for a few minutes, then it will fail afterwards. The weird part is that the ARP and mac address table entries are present.

I first noticed this issue when I was trying to troubleshoot why my wireless users were unable to obtain DHCP. I then resolved the issue by reconfiguring the WLC from scratch again, and the problem did not appear after that anymore.

I've attached the sample "problematic" configuration of my setup here. Hopefully someone here can advise me on why did this issue happen.

Thanks,

Regards,

Dennis Goh

P.s. usernames, passwords and enable passwords are "Cisco"

[Nicolas Darchis]

It can happen with this type of config. The best way is to configure the internal port towards WLC as trunk (so several subinterfaces with vlans) and configure them in bridge groups. From there you put the ip address on the "interface BVI x".

You can do the same with Vlan interfaces. But the idea is to not put the ip address on the internal port.

Nicolas

[Dennis Goh]

Hmm, not bad of an idea. I certainly didn't think of that before this. I searched on the net on how to save an IP segment for the NME-WLC and the forums lead me to that technique, that is why I used it

Anyway, I do not believe there is any problems with the router configuration because all this while, I have not touched the router. I've only played around with the WLC configurations. Maybe you could take a look at it and tell me where I went wrong?

Thanks!

Dennis Goh

[Dennis Goh]

Any ideas? Anyone? :3