Red Hat Bugzilla – Bug 129219
ftp client after kernel-2.6.7-1.494.2.2 no longer works to wu-ftpd server
Last modified: 2007-11-30 17:10:46 EST
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Description of problem:
Using kernel-2.6.6-1.435.2.3, the ftp client connects fine to a
wu-ftpd server, after upgrading to kernel-2.6.7-1.494.2.2, it no
Nothing else changed on the system but the kernel.
This message appears in the wu-ftp server logs:
Aug 5 06:08:40 6D:eosdata ftpd: lost connection to hostname
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. ftp to a wu-ftp server, client hangs
Actual Results: client hangs
Expected Results: ftp login banner
hmm...this may be localized to wuftpd on irix, but something in the
kernel update made this start to fail.
this is not a ftp problem, then
Could you get us 'netstat' output of the ftp connection, shown from
both the client and the server side ?
If there's something wrong with the network layer, chances are we
should be able to see the differences easily...
The server doesn't log anything in the netstat output, probably
because the connection opens and closes too fast for me to really
catch it. This is the syslog entry on the server.
Aug 5 10:33:45 6T:serverhost wuftpd: connect from clienthost
Aug 5 10:33:45 6D:serverhost ftpd: lost connection to
The client, however, seems to think it's connected to the server.
Active Internet connections (w/o servers)
Proto Recv-Q Send-Q Local Address Foreign Address
tcp 0 0 clienthost:1034 serverhost:ftp ESTABLISHED
OK, that looks like a networking problem indeed...
I have the same experience with NcFTPD.
ftp under 2.6.6-1.435.2.3 to NcFTPd works
ftp under 2.6.7-1.494.2.2 to NcFTP does not work
ftp under 2.6.6-1.435.2.3 to vsftpd works
ftp under 2.6.7-1.494.2.2 to vsftpd works
This is probably a duplicate of Bug 129204.
Indeed, putting net.ipv4.tcp_default_win_scale=0 into /etc/sysctl.conf
has me successfully connecting to the NcFTPd server in question, under
Confirmed for me too. I did this dynamically and it solved the issue.
Ok, I can now connect with ftp, but the data transfer is extremely
slow...and when I ctrl-c out of an ftp client session I get a
Same real issue as before, 2.6.6 kernel works ok (I can ftp the
kernel-sourcecode package from the server in about 7 seconds), 2.6.7
kernel takes forever. It grabs a big chunk of data to start, then
transfers about 1k every few seconds the rest of the time.
not sure if this info will help, but the machines having problems are
using the e1000 driver.
The speed problem seems to have been fixed with kernel-2.6.8-1.521
mass update for old bugs:
Is this still a problem in the 2.6.9 based kernel update ?
I no longer have an FC2 system to test with (they've both been
upgraded to FC3), but FC3 no longer appears to have the
$ uname -r
$ /sbin/sysctl net.ipv4.tcp_default_win_scale
error: 'net.ipv4.tcp_default_win_scale' is an unknown key
Everything does appear to work fine, though.
P.S. This looks like a duplicate of Bug 129204 .
Fedora Core 2 has now reached end of life, and no further updates will be
provided by Red Hat. The Fedora legacy project will be producing further kernel
updates for security problems only.
If this bug has not been fixed in the latest Fedora Core 2 update kernel, please
try to reproduce it under Fedora Core 3, and reopen if necessary, changing the
product version accordingly.