Time Capsule w/ AT&T DSL; Linux OK, Mac not OK

This is weird.

AT&T finally hooked up my DSL line, so I plugged the modem into my Time Capsule and set up a WPA2 wireless network.

My Linux netbook connected to the wireless network and started downloading its updates. It surfed the Net also.

My Macbook Pro connected to the wireless network and started backing up to the Time Machine drive on the Time Capsule. However, the MBP complained that its IP address was conflicting with another computer on the network. I tried rebooting the MBP; it made no difference. The error kept popping up, something like, "This IP address is in conflict with an existing machine on the network."

Why is it that the MBP has trouble connecting to the Internet but the Linux netbook doesn't?

Does a Mac require additional configuration to make it talk to the wireless router that's built into the Time Capsule (whereas a Linux machine doesn't)?

Desiderata - is a great poem but I digress

Typically no the Macbook Pro doesn't need to do anything more than linux.

You need to look at system preferences -> network -> airport -> advanced -> tcp/ip and see if anything else on your network is set to the same ip address

Also go to your Airport Utility -> double click your time capsule -> in the Airport Pane in the summary tab - you should be able to click the word Wireless Clients and see what MAC addresses are connected - if you see two of the same someone is spoofing your MAC address

Under Internet -> Internet Connection do you have it set to distribute a range of IP Addresses? Under DHCP what do you have as starting and ending DHCP? The default is usually a range of a 198 so I doubt it is that but you might as well ask.

I've actually made the assumption you are using DHCP instead of static addresses so if you are using static addresses then this is all out the window.

You hit the nail on the head. I was using DHCP for everything. Still, for some reason, the Time Capsule was allocating itself the IP address of 192.168.1.64, which was also the IP address that my Macbook insisted on trying to claim.

Instead of trying to figure out why my MBP wanted that IP address so badly, I changed the Time Capsule's IP address to 192.168.1.253 (one below the AT&T modem, which wants 192.168.1.254). That fixed the problem.

Thank you for your help, IvanLasston. You've made my day!

You will find less drama if you only have the modem handing out tthe DHCP and set the TC to bridge mode;


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