Arch Linux

Lyude

Member

Registered: 2010-10-03

Posts: 20

Very weird issue with Laptop's internet connection

So recently I upgraded to a new modem, since my old Motorola Surfboard finally decided to kick the bucket. I got it set up and everything seemed to work fine. Today however, I tried plugging my laptop into a wired internet connection to download package updates via yaourt and I noticed something very odd: All of the downloads would go faster then any of the other computers. The computers on my connection normally go to, at max, 1.6 MB/s (Megabytes, not bits). However, my laptop was hitting 3.8 MB/s at times. I thought this kind of cool, until it tried to verify the packages and said that the majority of them were corrupt. Mainly the slightly larger ones. (but some small ones too). I've never had this problem before, and it does not occur on wifi. I have an acer 6530g, using the network card built in, using the atl1e driver. It's connected to a router connected to another router that's connected to the modem. And I can guarantee it's only this laptop with the problem. The wifi is hosted on the first modem. The first router runs DD-WRT, and the second runs the stock Linksys software.

andersonmanly

Member

Registered: 2011-02-02

Posts: 7

Re: Very weird issue with Laptop's internet connection

It sounds to me like it might be a network configuration issue on your laptop's network card. I see that your laptop potentially has a gigabit Ethernet adapter. Perhaps the network framing is set up incorrectly? Not sure what the command is off hand to show all your network card parameters (ethtool?), but perhaps query this information and post it.

Lyude

Member

Registered: 2010-10-03

Posts: 20

Re: Very weird issue with Laptop's internet connection

I'm sorry, but what sort of information do you want with ethtool, and what command would I run with it to get that info?

Lyude

Member

Registered: 2010-10-03

Posts: 20

Re: Very weird issue with Laptop's internet connection

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 pause frame use: No
    Advertised auto-negotiation: Yes
    Speed: 100Mb/s
    Duplex: Full
    Port: Twisted Pair
    PHYAD: 0
    Transceiver: internal
    Auto-negotiation: on
    MDI-X: Unknown
    Supports Wake-on: pg
    Wake-on: d
    Current message level: 0x00000000 (0)
                  
    Link detected: yes
Hopefully thats what you want

andersonmanly

Member

Registered: 2011-02-02

Posts: 7

Re: Very weird issue with Laptop's internet connection

If eth0 is your network adapter, can you please run an 'ifconfig eth0' to get the output of that as well?

Lyude

Member

Registered: 2010-10-03

Posts: 20

Re: Very weird issue with Laptop's internet connection

eth0      Link encap:Ethernet  HWaddr 00:23:8B:2B:CC:F0 
          inet addr:192.168.2.123  Bcast:192.168.2.255  Mask:255.255.255.0
          inet6 addr: fe80::223:8bff:fe2b:ccf0/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:4559 errors:0 dropped:0 overruns:0 frame:0
          TX packets:4042 errors:0 dropped:0 overruns:0 carrier:6
          collisions:0 txqueuelen:1000
          RX bytes:976812 (953.9 Kb)  TX bytes:668689 (653.0 Kb)
          Interrupt:46

andersonmanly

Member

Registered: 2011-02-02

Posts: 7

Re: Very weird issue with Laptop's internet connection

I notice that 'carrier' is at 6 in your ifconfig which could indicate a bad cable. Have you had any issues with this cable before? I also came across some posts that suggest that it could also be a duplex mismatch between your laptop and the switch/router that it's connected to. I don't think the latter is the case though because it shows you're running at 100M/Full...which I assume your router is capable of autonegotiating to. I've had problems in the past with Sun servers and gigabit network cards not autonegotating correctly with the network switch they were connected to which caused all kinds of errors like the ones you're describing.

Lyude

Member

Registered: 2010-10-03

Posts: 20

Re: Very weird issue with Laptop's internet connection

The first thing I always try is switching around the cable, so I can tell you it's not that. As for the mismatching stuff, that could be the reason for it, however I'm pretty sure it isn't, I'll be trying it on another router soon though so we'll see then.