Ftp uploading problems (2.0.xx)

Rauli Ruohonen (raulir@fishy.pp.sci.fi)
Sun, 11 May 1997 00:29:03 +0300 (EET DST)

I seem to have some ftp uploading problems with all 2.0.xx kernels,
but downloading is not a problem. Uploading with ftp/ncftp for small
files just says that all data sent and reports insane KB/sec ratio, but
nothing is really delivered, and the connection eventually times out.
For large files it's sent veeeryy slowly, and it says "aborting
connection" because of a write error.

First I thought that this was because of my hardware timer problem,
as the problems seemed to go away after patching kernel to kluge around that.
The real reason for was that I tried ftp:ing to a host as slow as mine, and
the problem doesn't occur with those, only ones with faster net
connection. (weird huh?) Or that what it seems to be, of course it might
be random, I haven't really tested with many machines.

When I strace the ncftp process, I see that it writes the data and begins
read():ing, and never receives anything back. The socket is in FIN_WAIT1
state, so I think that the data is never delivered. I can't check for
sure because my tcpdump says "tcpdump: can't resolve symbol 'ether_ntohost'"

I have tried the pre-patch-2.0.31 (actually I'm running it now), but it
doesn't help.

Relevant info from ifconfig (after testing, no errors as you see):

ppp0 Link encap:Point-Point Protocol
inet addr: P-t-P: Mask:
RX packets:25 errors:0 dropped:0 overruns:0
TX packets:51 errors:0 dropped:0 overruns:0

And pppd:

May 11 00:16:35 fishy pppd[2011]: pppd 2.2.0 started by root, uid 0
May 11 00:17:08 fishy pppd[2011]: Serial connection established.
May 11 00:17:09 fishy pppd[2011]: Using interface ppp0
May 11 00:17:09 fishy pppd[2011]: Connect: ppp0 <--> /dev/modem
May 11 00:17:12 fishy pppd[2011]: local IP address
May 11 00:17:12 fishy pppd[2011]: remote IP address

fishy:/home/raulir>rpm -qa|grep ppp

The only thing I (_definitely_ not a kernel expert) can think for the
reason is broken nagle algorithm or TCP/IP stack..