I have recently installed OpenWRT (17.01.2) on both a WRT1900AC v1 and v2 and I do not have internet access - No IPv4 WAN address (see attached screen shot).  Has anyone else come across this problem?

I encountered the same problem on DDWRT, but with DDWRT, you can resolve the problem on the v1 hardware by using older DDWRT firmware and the v2 version did not yet have a solution.

I have Comcast and made sure I have rebooted my modem before connected the WRT1900 and it does not work on either version, so I had to use an older router with DDWRT just to provide internet access in my home until I figure out what is going on.

https://drive.google.com/file/d/0B1ULau … sp=sharing

How is your WAN interface configured in OpenWrt? How was it configured in DD-WRT?
Does your ISP have any special requirements?

Comcast typically doesn't have any special requirements.... Generally, all that's needed is a modem and a router. 

With the interface showing as not connected it makes me wonder if the cable isn't bad.

Correct - Comcast does not have any special requirements.  They just do DHCP on the WAN interface.  Unfortunately it can't be the cable because it is the same one that I'm using on both the WRT1900AC v1 and v2 (which doesn't work), and then when I connect the same cable to an older router on DDWRT, it works just fine.

As mentioned previously, in order to get is working in DDWRT on the v1 hardware, you had to use an older firmware version.  The older firmware uses kernel 3.1 and the newest used kernel 4.9 which breaks the WAN connection.

What modem is being used?

Also, did you start using lede from scratch or were there any previous configurations?