After having network connectivity issues over ethernet with the Overo Tobi, I followed directions given in the Wiki
This proved unsuccessful. I then (unwittingly) modified the /etc/network/interfaces file by uncommenting the line
iface eth1 inet dhcp
in addition to uncommenting the lines
iface eth0 inet dhcp
This had the effect that I can no longer reach the login prompt after rebooting, and the Overo seems to hang.
Are there workarounds to this issues, aside from getting a new Overo board?