For anyone searching, found this on Bitcointalk.org. Here is the short answer:
You have to telnet into the machine:
telnet 192.168.1.254 8100
username: root password: t1t2t3a5
For firmware built before 2017-12-22, the password is
12345678 apparently, haven’t tested.
Logs are found in:
/tmp/log/innominer.log /tmp/log/analys3.log /tmp/log/analys0.log /tmp/log/analys2.log /tmp/log/analys1.log /innocfg/log/miner.log /innocfg/log/upgrade.log