Just curious if you got your eth1 working. Are you using the DAC board w/ ethernet jack that pine64 sells?
I tried wiring up a magjack breakout board from Sparkfun but I'm not having any luck yet. I was able to use the command you gave for enabling eth1 and it sees the device, but it is constantly resetting and doesn't show a link on my switch. I'd just like to know if it works for anybody else before I get too much further.