looking for some suggestions on how to go about diagnosing this:

machine: athlon X2, gigabyte GA-K8VT890-9. identical issue on multiple identical machines, some with suse 9.3, some with suse 10.2.

the problem: the ethernet card sometimes doesn't activate properly on boot; trying to activate it using YaST or ifup gives no errors but also no connectivity.

it behaves fine when the machine is shut down or reset nicely from the XDM login screen.

but, if it ever needs or accidentally gets a hard poweroff or reset, or is shutdown or reset from the terminal, after booting again, no ethernet. it is not using dhcp, everything is configured statically. only error in the boot log is failure of the NIS bind. after rebooting from XDM, everything is fine.

(q: why are you hard-rebooting your linux box, you dope?? a: occasional wedges in apps like maya, etc; also, the reset buttons are poorly placed on the case and an easy target for users' knees)

it's not a huge problem, but is sort of irritating. i'm wondering what a clean shutdown does for the network device that a bad shutdown doesn't, that would carry through to the next boot.

My guess is: it's not a linux problem. Check your NIC to switch connectivity, including auto-sensing configuration. For example: if you have auto-sensing turned ON on your NIC but your switch is configured for 100Megs full-duplex and no auto-sensing - here is the problem.

bingo! thanks, fundamental. happiness is a warm and clean reboot.