1) May 18th, 2010
2) 3 days
3) MC3090
4) WM6.1 BSP9
5) 2125839 Customer is using the MC3090 WM6.1 BSP9 Fusion 2.57.23B with a WLAN connection and says that each time the device resumes from a suspend or warm boots it gets a new IP address. They said they have their DHCP server set for a 5 day lease time and that the issue only occurs with the MC3090 and only with Microsoft and Cisco DHCP servers. VoIP phones and laptops do not have this problem. If they use a Motorola RFS or AP or a US Robotics DHCP server they do not see the issue. They tested using an MC75 and an MC50 and saw the same issue. I also asked them to test on a clean out of the box device and they saw the same issue. I had them get netlog traces and my wireless colleague said he can see the MC3090 is sending an IP release and then an IP renew to the DHCP server. I tested the same unit here in tech support with a Microsoft DHCP server and could not reproduce this issue. Is there something else that can cause the device to release the IP like this? I'm not sure what else to check so I appreciate any help or ideas that you can give. Thanks, Tony
3 Replies
When the terminal is suspended, the WLAN radio is powered off and the network stack is collapsed. At the resume, the WLAN driver is unloaded and then reloaded. When it binds to the TCP stack, a DHCP DISCOVER/OFFER/REQ/ACK cycle will begin. There should be no release/renew being done on a resume. A warm boot begins with a suspend, so it will have the same function as a described above. The terminal will only ask for an address, it doesn't control the specific one retrieved. Does this site have multiple DHCP servers? The OFFER could be coming from different places and since the terminal will pick the first one it receives, sometimes one OFFER arrives before the other and sometimes it's the other way around.
Just one clarification on George's point, on a resume, if we connect to the same WLAN, I believe we will just perform the DHCP request, however it is up the server to allocate. You should see if you can duplicate it, and also get netlogs and possibly wireless traces to see what DHCP packets are actually being sent.
Hi George and Dave, The customer does have multiple DHCP servers on their network. I have transferred this case to my wireless colleagues to investigate this on the wireless network side. I will will provide an update as soon as I have some info from them. Thanks for your help. Tony