Weird Problem in Wireless

[praetoleiad]

Hi,

i have a weird problem on the cisco wireless infrastructure. i have a layer 2 guest vlan created on the LAN infra, this vlan is for the public wifi. Controller is 5508 and 1140 AP's

WLC details:

management ip on untagged vlan

public vlan on vlan 100 (layer 2)

virtual ip 1.1.1.1

dhcp for clients via wlan controller

gateway for this is via antlabs inngate appliance

vlan 100 interface details

172.16.100.1/24

172.16.100.254 (this is like a virtual IP, this is non-existing ip)

- antlabs provides gateway services (authentication, portal)

Problem:

users started complaining that loading of some sites are very slow,  but for google sites it's ok and working fine. facebook, youtube and  other sites load very slow.

[Leo Laohoo]

Have you compared this with the wired network?

[praetoleiad]

hi leo,

i have tried to connect via wired lan and the connection is fine. i am redirected to the login portal and browsing is fine.

the set-up is

AP >> Switch >> Core Switch >> Internet GW Appliance >> WAN Router

                                   "

                                   "

                              WLC

[Leo Laohoo]

Wireless signals OK?

Let me understand something:  Surfing to Google.com is fine but other sites ain't?   And you've compared this response with wired network and the wired network is fine?

[praetoleiad]

hi leo,

thanks for the support, weve figured out the problem. my colleague has experience the same wierd problem, that with his laptop, the browsing is ok while using the client's laptop, only selected websites are fine. this is an issue on the tcp mtu of the router. wireless infra has no problem and working fine, we had just suspected that it is in the wireless side, since when we tested it via LAN its working fine. appreciate the support extended.

[George Stefanick]

I spent a week troubleshooting an issue like that and learned it was the MTU on the wirelsss side and we needed to make adjustments to the WLC. After fighting that issue its one I will NEVER forget!

LOL

[praetoleiad]

yes i almost loss all my hair with that problem. it's really a weird problem. i haven't done anything on the wlc but on the router.