I have a SiS 900-Based PCI Fast Ethernet Adapter. It worked fine with RH 9 (and there is no network problem at all). Since I upgraded the machine to FC5, the Ethernet does not work anymore. The ifconfig displayed the eth0 without IP4 address (only ip6 ip address). I did eth0 down and up with a correct IP4 address, but then it failed to ping any IP address. I've installed FC5 to 5 of my friend's machines without problems, but this one got me. Appreciate any helps to resolve this problem.
Re: PCI Ethernet
"..but then it failed to ping any IP address. "
any IP address meaning on the local subnet?? or IP address outside of your gateway router?
If the latter, you have probably forgotten to set your default route. Try
route add default gw xxx.xxx.xxx.xxx
where xx.x is the upstream router IP