[4.5-R]Problems Uploading via FTP, etc.

[Michal Mertl]

On Thu, 4 Sep 2003, The Jetman wrote:

>
>     While this isn't specifically a mobile computing problem, I *believe*
> it's due to my Orinoco Silver wireless card *under* FreeBSD.

More appropriate forum is probably -questions or -net anyway.

>
>     About eighteen months ago, I converted a Windows 98-based wireless
> gateway/router to FreeBSD 4.5-RELEASE and never looked back.  It took a
> week to get it working properly, but once it was, I was totally sold on
> FBSD.  I chose it bec I wanted the integrated firewall/bandwidth limiter,
> a well-respected TCP stack (I've owned Stevens' classic TCP/IP Illustrated
> for many, many moons), and solid, console-based, scriptable OS.
>
>     My question:  using /etc/rc.firewall as my starting point, I've made
> a fairly customized firewall for my office.  I can look in on the router
> from outside via SSH, PING the outside world, etc (which the stock rc.firewall
> doesn't do.)  What I can't do is upload most files from either my FBSD
> router or from the interior machines on my LAN (the gateway/router also NATs.)
> That's one of the few problems I didn't have under Win98 w/ Sygate, hence it
> isn't due to some quirk from my wireless provider's network.
>
>     For example, today I logged into the router and tried to upload a
> couple of files to my ISP's Windows NT FTP server, using the stock FTP
> client.  The initial file (a < 1K text file) was there in no time, however
> the 2nd file (57KB) stalled after transferring the 1st 10KB of the file.
> This behavior is reproducible, bec it happens every time w/ any file
> that's approx > 10KB.  Below are the only network-related customizations
> I've made to the system:
>
> ####  drop SYN packets destined to a non-listening tcp/udp port to protect
> ####  against stealth port scans
> net.inet.tcp.blackhole=2
> net.inet.udp.blackhole=1
> ####  increase TCP window size for increase in network performance
> net.inet.tcp.recvspace=65535
> net.inet.tcp.sendspace=65535
>
>     I think I got these from an article on onlamp.com, regardless I've
> played w/ the settings, and all I can do is change the point that the FTP
> upload stalls.  HTTP uploads also seem to stall, as well.

Your changes don't change anything important for actual transfers in
progress.

>     My Wi-Fi connection is pretty fast (512Kb/s), so most xfers shud be
> almost instantaneous.  This is certainly the case of downloads.  It's
> not the firewall, bec I can switch to the open config of rc.firewall
> and the symptoms are the same.  I can't think of anything else to change,
> but then there's a lot I still don't know about FBSD.

Your problem is probably caused by packet loss on your Wi-Fi connection.
TCP has several mechanismuses to recover from lost packets. One of them is
the New Reno algorithm. You can try disabling it with
net.inet.tcp.newreno=0 because it has been broken for long time.  There
were some fixes to it well after 4.5 was released so you could try
updating to 4.9 as well.

-- 
Michal Mertl