Hi,
I am having problem with wired networking.
Please consider me a linux noob but i know little bit.
server hp proliant n36l microserver
OS : started with ubunto 11.10 desktop. the network was slow
went on to fedora 15 and it was the same. now it has ubuntu server 11.10 and it is still slow (very high packet loss)

I have configured
1. disable IPV6 (by adding in /etc/modbprobe.d/aliases - alias word)
2. static ip (by adding in /etc/network/interfaces)
3. added dns (my router) (in /etc/somewhere as i am at office)

simple ping to router (ping -f -i 1 192.168.0.1) returns an astonishing 80% packet loss.
pinging google.com returns with 95% packet loss

the NIC is integrated gigabit NC107i (bcm5723).

Please advise of anything else I have to do.

I can borrow a router from a friend to test if it is the router's fault
(the router working fine with windows 7 laptop wired/wireless)

I am out of options now

What about iptables on Ubuntu and on your router? Maybe there is some protections from flood. You must check other PC connected to this router and also other router to narrow malfunctioning device.

not just the flood ping.
a normal ping 192.168.0.1 gets packet loss

Can you check what speed and duplex the switch/router thinks you are, and what speed and duplex the computer thinks it has. The autorecognition may have missed.

I bet the speeds match, or you would have no network. If the duplex is off (one side full, the other half) you can get exactly those symptoms.

I dont know the reason but it was the network port on the router.
two of them had problems (no problem with windows wired network though) with linux and one port was working fine.
glad I checked with changing the ports.