On 2013-08-18 12:25:59 -0500, Stan Hoeppner wrote: > On 8/18/2013 10:31 AM, Vincent Lefevre wrote: > > On my laptop, Ethernet has been limited to 100 Mbps for a few days. > > Nothing changed on the network side. Just a few upgrades on the laptop > > (Debian/unstable). Any explanation? > > Gigabit ethernet is fully auto negotiating at the hardware level--a > software update shouldn't cause negotiation to drop to 100. GBE uses > all 8 conductors of category 5e/6 cabling, fast ethernet uses only 4. > If it's negotiating to 100, I'd say you have a bad cable, connector > (cable or receiver port), or switch port.
The Ethernet cable was the same as before, and I've tried a second one, and it's still 100. I've also tried another port on the switch. > Given this is a laptop, I make the educated guess that you > plug/unplug regularly putting wear stress on the cable and > connectors. It's not regular (the laptop is usually at home and remains connected). I take it with me only when I'm off for several days. But the problem occurred just after being back from holidays, where I took the laptop with me; I didn't use the Ethernet port there, but the laptop has moved a lot in the train. To confirm whether this comes from the laptop, I'll try with the switch at my lab tomorrow (and I could compare with the desktop computer, for which the speed is 1000). > In this case you should check the 8 angled pins in the laptop RJ45 > receptacle to make sure none are broken or bent. If one of the 8 is not > making solid contact with the corresponding cable connector pin, 100 > Mbps link speed will be the result. If it is damaged the laptop will > require depot service to desolder and replace the receptacle. If the > receptacle doesn't appear to be the problem, replace the cable with a > known good cable or a new cable. Frequent bending of cables during > insertion/removal can cause stress breakage of the tiny cable conductors > which are normally 26 or 28 AWG, especially at the termination connector > junction. OK, thanks for this very detailed information. -- Vincent Lefèvre <vinc...@vinc17.net> - Web: <http://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <http://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon) -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20130818190504.gb6...@xvii.vinc17.org
