Oneiric: lost network connection & desktop

[Liam Proven]

Upgraded to 11.10 64-bit last night. (AMD Athlon X2 5200+, 4GB RAM,
nVidia GTX250 graphics, dual onboard NICs.)

Last night, it worked, even after the first reboot or 2.

Today, X loads but nothing else - blank background, responsive generic
X mouse pointer, nothing else.

Dropping to the CLI, I don't have an IP address or Internet connectivity.

During bootup, there is a ~1min pause when it says it's waiting for
network configuration. Nothing happens, it seems. It then says it's
waiting for another minute, then it (I guess) gives up and loads x.org
but the login manager doesn't start.

Any suggestions of where to start troubleshooting?

I'm posting from Win7, which is unaffected and seems fine. It only
took 4 hours to download 1.039GB of fixes and updates to Windows
itself, plus the 5 reboots' worth of app updates. :¬(

-- 
Liam Proven • Info & profile: http://www.google.com/profiles/lproven
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