I am a new comcast customer. The guy installed the modem, but left before I could verify my internet connection via my router, a Linksys N. I have the DNS entries, but I'm not sure if I should set automatic DHCP. I have done that and cloned my MAC address, but to no avail. Help! Can anyone tell me why this router worked with my old verizon, but not comcast. I have changed the username, etc. Are there settings I'm missing? I put hsd1.nj.comcast.net in for the hostname, but left domain name blank. I don't see a place to put the DHCP server name or the default gateway. Should I use a static IP? I don't think so, but please help. I have VOIP, so my phone is out and we stream TV, so we're really hosed....
You should have it in DHCP, you do not need DNS entries, do not clone your mac address, and do not use a host name from Comcast.
DHCP is plug and play with Comcast HSI. You do need to power down the cable modem any time you change the device connected to the cable modem, or if it's a telephony eMTA modem for Comcast Digital Voice, you must press the reset button on the back panel of the eMTA to reset the device everytime you change the connected device.
It is simple plug and play, you are over complicating things by putting in those manual entries.