I finally got my Microcell working again last night when I plugged it directly into the cable modem. I let it sit over night, and it was still working this morning. However, when I went back to the configuration I was using prior to Sunday -- when everything worked -- the constant 3G blinking light returned. The configuration that worked prior to Sunday was as follows: cable modem to DIR-655 Router, and DIR-655 router to M-Cell. Now that configuration no longer works.
So, that leaves me with the question of how, exactly, the DIR-655 should be set up for the M-Cell to work properly? As noted, it worked fine prior to Sunday with the current configuration, but won't work now when plugged into the DIR-655. I have tried the recommended configuration settings listed in the manual for the DIR-655 to no avail. AT&T and D-Link don't have a clue.
Thanks for any info on this.
A number of people seem to have similar complaints on the AT&T forums. I don't work with that device, but I found this:
Which suggests it just uses NTP, DNS and IPSEC with NAT traversal, which should have no problems at all with your setup.
Since AT&T supports the device, your best bet is to probably call them.
One possibility is that the NAT timeouts on the DLink are too agressive for the Microcell. If you are technically inclined, you might want to see what is going on using Wireshark. Does powercycling the Microcell temporarily fix the problem? How long does it run before the 3G LED links again?
Thanks, but after a couple of weeks of fighting with AT&T, the problem was resolved ... I swapped the unit for a new one, and
all works well. I obviously had a defective unit, but AT&T didn't seem too anxious to stand behind the warranty and
swap it out.