I am building a Source Mage system on a laptop (kernel v2.6.22), and am having a bit of frustration with the TCP protocol. I have a SiS191 ethernet card; to get that to work, I followed this
excellent howto on altering the driver, and the card does seem to be working fine.
I can ping sites, my DNS is working, and I can sometimes visit certain
websites: Google, bbc.co.uk, and a few other big ones. However, when I try to visit other sites (or use the Source Mage equivalent of 'wget' to download package files to continue building my system), I get messages like:
'HTTP request sent; awaiting response...'
And then a timeout. Every time. FTP gives similar issues.
Now, this sounds awfully like the window scaling problem
which was brought into the open with kernel 2.6.17. One thing that might be different in my case is that the window scaling problem seems to affect only a handful of websites which are sitting behind broken routers, whereas my problem is with almost every
website, except, perhaps, ones that are cached somewhere already (Google, BBC)...but that could just mean that the broken router is only a step or two upstream from me - however I'm fairly confident it's not the household one.
I have tried the following suggested fixes for that problem:
- setting /proc/sys/net/ipv4/tcp_window_scaling to 0
- setting wmem and rmem values to the pre-2.6.17 ones
- various other, similar suggested fixes for window scaling - all the ones that come up in general Google searches, which are basically variations on the themes of the above
- and done those in various ways (not that it should matter): echoing directly to the file, putting the new values in sysctl.conf etc.
None of these have worked.
Is this a window scaling issue? If so, does anyone know of any other fixes (I'm not scared to try 'complex' things); if not, does anyone know what else it could be?
(I can try to get tcpdumps if someone thinks that's necessary for troubleshooting...I've just avoided it thus far because it is a pain, given the minimal system I have and my inability to download packages, as I don't have tcpdump on the system!)
Thanks for any help/advice anyone can offer.