Gigabit NIC not negotiating to gigabit.

d2490n · 03-24-2014, 08:03 PM

Hi,

I am running a home media server on Debian 6.0.7 with 2.6.32-5-amd64. I am sharing files over NFS and it used to work great but now I cant seem to send data any reasonable speed.

If I start a file transfer with scp it will start at ~2.3MB/s but then it quickly drops to ~220KB/s. In the past I have been able to play video over the local network without any trouble but now its basically impossible.

My network cards are as follows. I have reproduced this with both cards.

Code:

root@ REDACTED:/home/ REDACTED# lspci | grep Eth
00:19.0 Ethernet controller: Intel Corporation 82567LM-2 Gigabit Network Connection
01:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection

Ethtool tells me that the NICs are running at 100Mb rather than Gigabit.

Code:

root@ REDACTED:/home/ REDACTED# ethtool eth0 | grep 'Speed\|Duplex\|Advertised link modes'
        Advertised link modes:  100baseT/Full
        Speed: 100Mb/s
        Duplex: Full

Changing the speed with ethtool kills the connection completely, I have to change it back to 100M to even get DHCP.

Code:

root@ REDACTED:/home/ REDACTED# ethtool -s eth0 speed 1000 duplex full        
root@ REDACTED:/home/ REDACTED# ethtool eth0 | grep 'Speed\|Duplex\|Advertised link modes' 
        Advertised link modes:  1000baseT/Full
        Speed: Unknown!
        Duplex: Unknown! (255)

Please let me know if im missing something obvious or if I provided incomplete information.

Thank you in advance for any advice or insight you can offer.

Emerson · 03-24-2014, 09:25 PM

See your dmesg. Your switch/router may be dying. Your cables may be going bad. I had similar issue when I switched from 100 Mbit/s to 1 Gbit/s. I had to fix the damaged cable that worked fine with 100 Mbit/s.

d2490n · 03-25-2014, 06:48 PM

Thanks for the response, Emerson. Cables/router dose sound like the next logical step. I will go ahead and swap out the cables first, I hope I don't need to buy a new router but if it comes down to it then I guess I will just have to.

jefro · 03-26-2014, 02:50 PM

If you have another device to test gig connection I'd do that before I bought a switch. Suppose you could make a loop back connector to see if gig works locally too.