Re: Very slow network - Ubuntu

["A. Ben Hmeda" <abh@canada.com>]

Marty wrote:
> A. Ben Hmeda wrote:
>
> > I have an Internet router for sharing cable Internet connection. 3 PCs 
> > plugged into this router, class C network, I think. All with static 
> > IPs 192.168.1.2,3 and 4. Gateway (router) is 192.168.1.1 DNS is my 
> > ISP's 64.71.255.198 I am using 100Mb Ethernet and 10/100Mb router. My 
> > Internet connection speed is only 1Mbps (max) My internet download 
> > speeds range from 90kB/s to 114kB/s. Under Ubuntu, they crawl at 
> > 15kB/s to 25kB/s max! under static IP setup or dhcp setup.
>
> I forgot to mention before, that details about your NIC and kernel may 
> also be relevant.  See below.
2.6.15-28-k7 #1 SMP PREEMPT Thu Feb 1 16:36:09 UTC 2007 i686 GNU/Linux
> > The machine with the problem is my AMDSMP. I have had absolutely no 
> > problem with network speed (internal and external) until I installed 
> > Dapper. As it is now, it is a dual booting machine (win2k and ubuntu)
>
> The point I was trying to make is to determine whether the problem (with 
> Ubuntu) exists in the LAN traffic as well as in the internet connection 
> traffic. Whether the slowdown also occurs in LAN traffic, or 
> alternatively, only with internet traffic, this information would tend 
> to narrow down the problem a great deal and could help point to the cause.

It exists on both lan and wan. I tested using file transfer (smb) 
between my machine and kidpc (win2k) and found that by re-issuing the 
command /etc/init.d/networking restart, the transfer speed within LAN 
almost doubled.

> > Previously, it ran Debian Sarge, Fedora Core 4 and 5, alongside win2k 
> > without any problems. Presently, my network speed is fine under 
> > windows, was fine under Sarge, Fedora 4 and 5 on the same machine, 
> > except for ubuntu.
>
> Although that makes physical layer issues less likely, it doesn't 
> eliminate them.  The only way to completely eliminate physical layer 
> issues is to swap cables, router ports, and (lastly) NICs.  These kinds 
> of tests should probably be the first things to try because they are so 
> easy to do, although they have a very low probability of being the cause.
>
> > As I was poking around, trying to figure this out, I noticed that 
> > network speed is drastically improved, back to 90kB to 114kB under 
> > Ubuntu when, in GNOME, I open the System>>Administration>>Networking 
> > and just click OK, without actually changing anything! This makes no 
> > sense to me and I have no explanation for it, it certainly does not 
> > change the content in my /etc/network/interfaces but I was able to 
> > duplicate the steps with same results every time. Is the 
> > System>>Administration>>Networking>>OK the same as 
> > /etc/init.d/networking restart?
>
> I don't know, but you could find out by executing the command on the CLI 
> as root.  If it fixes the problem then it could be a NIC driver 
> initialization issue.  Then you should start experimenting with 
> different drivers and NICs to narrow down the cause.  Otherwise we may 
> not be able to exclude the "ghosts" hypothesis proposed by another list 
> member.  :O

Re-issuing the command fixes the problem, I will live with it as I have 
no more PCI slots left to install another NIC.

Thank you all so much for the help.