[SOLVED] Some sites which I cant access for some weird reason

MONODA · 2009-06-25 22:24:26

For some reason, whenever I am using any linux distro on my computer, I am unable to access (the download speed goes down to just a few bytes per second so the connection always times out) a few sites. These sites are always: any wiki site (arch wiki and wikipedia included), streaming youtube vids I have the same problem, and a few other sites which I dont visit that often. I dont have this problem in windows or in any of the other computers on my network (macs, windows and linux) so I know the problem is from my computer setup in linux. The weird part is that I get this problem in all linux distros. Any ideas? Any files I should show you (I really know nothing about networking so I dont know where to start). Thanks in advance.

Last edited by MONODA (2009-06-26 05:31:30)

arkham · 2009-06-26 00:37:16

It could be anything, you're not giving much info..
Can you actually connect to those websites?
Try running to command "dig site_you_cant_access" to see if your dns works, then try with "ping site_you_cant_access".

ralvez · 2009-06-26 03:25:45

Disable IPV6 if it's on.

R.

Bogart · 2009-06-26 03:53:50

You might also want to try, as root:

echo 0 > /proc/sys/net/ipv4/tcp_window_scaling

If it makes a difference, to make the change automatically at boot you can add a line to /etc/sysctl.conf with the following:

net.ipv4.tcp_window_scaling = 0

And if it doesn't make any difference, just revert the change with "echo 1 > /proc/sys/net/ipv4/tcp_window_scaling" (or reboot the computer, if you prefer).

MONODA · 2009-06-26 05:29:19

I don't believe it! Bogart, you saved me! To think something so easy to do could cause such an annoying problem! Thank you so much!
I was tried disabling ipv6 but I didn't notice a difference in performance so I just enabled it again since I guess there's no harm in having it.
Once again, THANK YOU!!!

Bogart · 2009-06-26 07:29:39

Glad you solved it! I have the problem since TCP window scaling was implemented in Linux, so I'm used to disable it ever since.

For the record: This problem happens because some routers are "broken" and don't deal well with big sized TCP packets (or something like that). Linux was the first to implement the window scaling (kernel 2.6.17, IIRC), but then also BSDs and Solaris did. Finally Windows did it too (in Vista), though it seems in a more moderate way. However, those suffering from this problem would also benefit if they disable the feature in Vista (http://www.speedguide.net/faq_in_q.php?qid=247). I don't know about OS X, but if Leopard doesn't have it (which I doubt), probably Snow Leopard will.

MONODA · 2009-06-26 07:54:17

Thanks for the info. Now that I think of it, I remember having similar problems with vista (though the sites I could not access were different than the ones listed above) but not in XP.

MONODA · 2009-06-27 13:01:06

Wait... the problem reappeared again, but only with wikis and its not as bad as it was but I just cant opne the arch wiki at all. I changed everything the way Bogart said but the problem is still here. Any advice for network optimization

Last edited by MONODA (2009-06-27 13:31:34)

Arch Linux

#1 2009-06-25 22:24:26

[SOLVED] Some sites which I cant access for some weird reason

#2 2009-06-26 00:37:16

Re: [SOLVED] Some sites which I cant access for some weird reason

#3 2009-06-26 03:25:45

Re: [SOLVED] Some sites which I cant access for some weird reason

#4 2009-06-26 03:53:50

Re: [SOLVED] Some sites which I cant access for some weird reason

#5 2009-06-26 05:29:19

Re: [SOLVED] Some sites which I cant access for some weird reason

#6 2009-06-26 07:29:39

Re: [SOLVED] Some sites which I cant access for some weird reason

#7 2009-06-26 07:54:17

Re: [SOLVED] Some sites which I cant access for some weird reason

#8 2009-06-27 13:01:06

Re: [SOLVED] Some sites which I cant access for some weird reason

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