You are not logged in.
Just added a GS105 gigabit switch to the LAN at my parents house. The Arch box is only connecting at 100 Mbps despite the fact that it has a gigalan PCI NIC in it. Note that I don't have physical access to the machine is at my parents house and they are absolutely no help with Linux, so I have to troubleshoot this remotely via ssh or vnc.
If I query eth0 with ethtool it does indeed support gigalan speed:
# ethtool eth0
Settings for eth0:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supports auto-negotiation: Yes
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Advertised auto-negotiation: Yes
Speed: 100Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 0
Transceiver: internal
Auto-negotiation: on
Supports Wake-on: pg
Wake-on: g
Current message level: 0x00000037 (55)
Link detected: yes
If I force it with the -s command, the ssh session I'm in seems to freeze for about 30 sec then resume:
ethtool -s eth0 speed 1000 duplex full
Link speed is still 100 Mbps.
Suggestions are welcomed!
Last edited by graysky (2010-07-31 02:33:51)
CPU-optimized Linux-ck packages @ Repo-ck • AUR packages • Zsh and other configs
Offline
It might be the old auto-negotiation at both ends of the link not agreeing who sets speed/duplex for link at gigabit speed. You may want to turn off auto-negotiation on your PC's NIC and try again.
Last edited by CountDuckula (2010-07-31 04:08:10)
Offline
Are you sure you're using Cat 5e or Cat 6 network cable? Standard Cat 5 won't support gigabit speeds.
Are you familiar with our Forum Rules, and How To Ask Questions The Smart Way?
BlueHackers // fscanary // resticctl
Offline
@CD - Remember that I'm doing this via an ssh session. As a fail-safe, I set "shutdown -r 60" running in the background just in case I hosed the network! I tried your suggestion, but doing so killed the network:
# ethtool -s eth0 autoneg off speed 1000 duplex full
Again, the ssh window just hung after I hit enter. I couldn't ssh into the machine until it rebooted.
@fukawi2 - Good point. I know the main run from the switch to the wall is Cat5e, but I'm not 100 % sure that the patch cable from the machine to the wall is cat5e. I will have them check it and post back here. Is there a Linux utility that can make some qualitative measurement of cable quality? I remember that Realtek had some diagnostic that ran under Windows that would some how diagnose the individual pairs of a patch cable. I searched around but found nothing like this for Linux
Last edited by graysky (2010-07-31 09:38:46)
CPU-optimized Linux-ck packages @ Repo-ck • AUR packages • Zsh and other configs
Offline
@fukawi2 - Good point. I know the main run from the switch to the wall is Cat5e, but I'm not 100 % sure that the patch cable from the machine to the wall is cat5e. I will have them check it and post back here. Is there a Linux utility that can make some qualitative measurement of cable quality? I remember that Realtek had some diagnostic that ran under Windows that would some how diagnose the individual pairs of a patch cable. I searched around but found nothing like this for Linux
Not that I know of, sorry. Don't forget the cable in the wall too. Stupid cablers only put Cat5 between my office and my house when I asked for 5e so I can only get 100mbps from my office to my house
Are you familiar with our Forum Rules, and How To Ask Questions The Smart Way?
BlueHackers // fscanary // resticctl
Offline
Not that I know of, sorry. Don't forget the cable in the wall too. Stupid cablers only put Cat5 between my office and my house when I asked for 5e so I can only get 100mbps from my office to my house
I did all the runs in the walls and I know I used Cat5e (the same spool that I used for my own house which runs GigaLAN just fine).
PC <---> Wall <--------------------> Switch
Right now the only wildcard is the PC to wall connection.
CPU-optimized Linux-ck packages @ Repo-ck • AUR packages • Zsh and other configs
Offline
I did all the runs in the walls and I know I used Cat5e (the same spool that I used for my own house which runs GigaLAN just fine).
Fair enough then
Wish I had the skills (and more so the patience!) to do it myself!
Are you familiar with our Forum Rules, and How To Ask Questions The Smart Way?
BlueHackers // fscanary // resticctl
Offline
Well, it wasn't the patch cord. It has been swapped with one that works @ Gigabit speeds on another machine. I can only conclude that it is either the switch, or the run that I installed.
Does anyone else have any ideas?
# lspci | grep net
00:09.0 Ethernet controller: D-Link System Inc Gigabit Ethernet Adapter (rev 11)
The damn NIC is clearly Gigabit able and I've used it before on my own network @ 1000 Mbps.
Last edited by graysky (2010-07-31 23:58:52)
CPU-optimized Linux-ck packages @ Repo-ck • AUR packages • Zsh and other configs
Offline
I'm out of ideas, unless it's a really long run, or like you mentioned, something in the punch down isn't quite right...
Are you familiar with our Forum Rules, and How To Ask Questions The Smart Way?
BlueHackers // fscanary // resticctl
Offline
Are you sure you're using Cat 5e or Cat 6 network cable? Standard Cat 5 won't support gigabit speeds.
FYI CAT5 can run at gigabit - it's just that it gets a litlle less happier doing it if the run gets close to the 100M mark. I had gigabit working fine at a distance of 50M over CAT5 but YMMV.
Offline
Thanks for the replies. Looks like this is a problem with the netgear being a piece of shit. Have a look at all the folks in the newegg reviews reporting a similar problem with some NICs.
Looks like I'm out $40 on this one...
CPU-optimized Linux-ck packages @ Repo-ck • AUR packages • Zsh and other configs
Offline
Thanks for the replies. Looks like this is a problem with the netgear being a piece of shit. Have a look at all the folks in the newegg reviews reporting a similar problem with some NICs.
Looks like I'm out $40 on this one...
Yeah that happens sometimes due to poor chip sets involved, I had to hard code speed/duplex between two Cisco switches on occasions as they couldn't work it out for themselves - so spending thousands don't help sometimes. Netgear feature towards the lower end of my scale for reliable stuff...
Offline