WZR-1750DHP troubles with Motorola/Arris Surboard SB6141 Modem

[SJCBrian]

I've had my 1750 for more than a month working fine with my old Comcast cable modem which I think was Docsis 1.0.  Comcast is pushing upgrades to Docsis 2.0/3.0, so I purchased my own Motorola/Arris Surboard SB6141.  I installed the new modem today and after calling Comcast, I got it provisioned and running.  However, I could not get the Buffalo 1750 to work with it.  With my PC directly connected to the Modem I got internet access, and I even reset the 1750 to factory defaults and it would not provide access.  I could get to the router through the wireless network, but it showed there was no internet access.  I reset the modem and router multiple times with no luck.  I gave up on the connection wizard and also tried using DHCP but the symptoms seemed to be that I was not getting DNS configured correctly.  Finally, I got out my old Cisco/Linksys wireless router and hooked it up and it worked the first time.  Any suggestions? 

One big question I have is whether the WZR-1750DHP supports IPv6 or not. The SB6141 supports IPv6 and with the Cisco/Linksys router, I can see that it is automatically being assigned an IPv6 DNS server address. 

Thanks in advance for any help,

Brian

[SJCBrian]

After enabling all of the VPN pass-through settings including IPv6 pass-through, I tried again.  I powered off both the router and the modem, then turned on the modem and waited until it was running and then powered on the router.  And now everything is working. 

[mother]

Thank you! Was going nuts, and for whatever fsm-forsaken reason, that worked!