Bottom line: From a power on boot or soft reboot, the device does not come up if there is any PC connected to eth1
ITUS Networks Shield with OpenWrt SNAPSHOT r19093-9851d4b6ce / LuCI Master git-22.058.70382-d29400e installed
10 Mbps ISP connection (NOT a typo)
Netgear router 100 Mbps (WAN + 4 LAN)
1 Gbps switch whose uplink port is connected to a router port
ITUS Shield eth0 WAN
ITUS Shield eth1 LAN
Tests which DOES NOT make it work (laptop on ITUS eth1)
ITUS WAN eth0 --> router 100 Mbps port
ITUS WAN eth0 --> switch Gbps port
I still have a PC with a COM port so I connect a DB9 to RJ45 Cisco cable to the console and boot (5 times; 2 GOOD, 3 NOT) and save the logs.
I compare and notice the only difference when NOT working is: eth1: 1000 Mbps Full duplex, port 1, queue 1
I figure maybe it is to do with the speed differences. eth0 is 100 Mbps
So I do the original 2 tests above again but run the ITUS LAN eth1 wire through a 10 Mbps hub making eth1 slower than eth0. NO GO
Using a sniffer I do the original 2 tests above again but this time run the ITUS eth0 WAN wire through my 10 Mbps hub and now I know why. There is no DHCP request. I see broadcasts on the wire like SSDP from my wireless printer and ARPs and other stuff but not a peep from the ITUS WAN port.
So what is wrong?
Any test above with NO connection on eth1 gives me a working router to which I can then connect to eth1 and access it.