Roaming problem

[mschenk]

Hi,

I have a strange problem with a wireless network that I think is related to the Procurve switches I am using.

In one of our hotels we recently installed a wireless network from Ruckus wireless (controller based). All APs are connected to E2520-8-POE switches. The E2520-8-POE are connected to either E2510-24 or E2510-24G switches. There are in total 15 switches in the hotel which are partly cascade connected. I use one VLAN for the management of the switches and APs and one VLAN for the guests access.

The problem is that when a client roams to an AP that is connected on another switch then the AP it was last connected to, the communication stops for 30sec upto 5 minutes. The client is associated to the WLAN and on the WLAN controller you can see that the client has roamed succefully but on the client there is no outgoing data (On the wifi NICs activity you see 0 bytes Sent while Received bytes are counting). When the client roams to an AP located on the same switch, there is no problem. Even if you disable/enable the wifi NIC on the client it doesn't always communicates properly.

I have been in contact with several Ruckus technicians but they all say that it must be the network. I have checked the VLAN settings on the switches over 10 times but can't find any mistakes. I have this behaviour with all kind of devices (I tested with W7 clients, iPhone/iPad and an Android smartphone). I tested with a fixed IP address to eliminate DHCP problems, I tested with open WLANs without encryption or authentication but it makes no difference.

It looks to me that the switches need a very long time to update their tables in order to know to which switch the client belongs to. I know too little about layer 2 stuff so is there anyone out there that can help me further with this problem?

[Richard Litchfield]

Check your spanning tree settings. Make sure the core switch is the root bridge with the lowest spanning tree priority

priority 0

 Switches further away should have higher numbers, typically over 8 (32768). Make sure your Ruckus devices aren't also doing spanning tree.

You could always get some demo kit of the HP MSM wireless and trial that - at least you wouldn't have any finger pointing. And you could check out the MSM317 in room access devices (see the marketing video at  http://www.youtube.com/watch?v=Mm0bdfFfgFI ; start at ~2min!)

[mschenk]

I am not using spaning tree.

But I found that the problem was in the 2510-24G switches which had an old firmware with a bug.

MAC Address (PR_0000009750)

— If a client moves from one port or switch to another,

the MAC address is not relearned on the new port until the MAC address timer expires on

the original port.

Update to the latest FW fixed the whole problem. I am happy I solved the problem, it is just a pitty I was looking in the wrong direction first (Ruckus Wifi system) and spent time an money on the wrong thing.

//Marco