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Epic DHCP roaming fail.

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Deepseadata

Technical User
Jul 10, 2008
123
DE
Hehehe,

Hey everyone. I'm working on a problem where wifi clients from two different Vlans (Guests and Crew) are having problems maintaining a connection when roaming around a large yacht. Their DHCP servers are on different two different SBS 2003's.

We've got about 20 Strix access points with multiple ssid's connected to 5 different switches finally coming together on one switch. This one switch is then connected to a Small Biz Server 2003 that acts as a router and also a DHCP server for the Guests Vlan. The Crew Vlan is passed through this SBS 2003 "router" to the Domain Controlling SBS 2003 server that runs DHCP for the Crew Vlan.

I'd usually have a Cisco L3 switch doing DHCP for both Vlans and doing the routing.... I've got to make this work somehow though. The StrixSystems AP's have one main "controlling" AP that is pretty useless and doesn't have much flexibility. The Hirschman switches are pretty useless, too. I was hoping to move the DHCP service closer to the clients and put it on the the main Hirschman switch instead of the SBS's. The Hirchman Switch doesn't have a DHCP server in it though.

So here's a better description of the problem. A user logs onto the Crew wifi network. It serves her an address. She gets up and walks 100' (onto another wifi access point). She (sometimes) can no longer access the internet. She then walks back to where she originally logged in... and can't get back in. The windows client just says "attempting to authenticate" and the window pops up "Unable to join network." If we disable/enable the wifi interface on the client we can sometimes get back in.

Often the only way we can get the client back onto the network is to reboot the AP's. The previous administrator was used to rebooting ALL networking devices in order to get the wifi working... until is slowly becomes useless again as people take their phone or laptop to another location onboard.


Here's what I haven't tried.

-I haven't looked to see what access point she originally logged into and rebooted just that AP.

-I haven't learned enought about SBS 2003

Can anyone throw me a bone as to what tools I should use to better troubleshoot this problem?

Thanks!
 
Roaming back and forth between SSIDs like this is a challange, regardless of the SBS or DHCP issues. The client is often easily confused, especially when the original channel and SSID are "almost" close enough to work.

I set up a network in a library near my home. Because of the distances and "density" of the space, I needed to add a second AP. I used the same SSID and channel on the 'subordinate' AP and wired them together. I don't know if your APs would support that kind of situation, but if they did, it would certainly ease your pain.

There are some differences:
- I wasn't using the brand of AP you are using.
- DHCP was handled by the "primary" AP instead of a DHCP server on an SBS server.

 
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