On 10 September 2012 08:09, Johannes Frank <johannes.fr...@kisters.de> wrote: > Hello together. > > I have a weird problem which unfortunately leads to production halts at > two of our customers so I urge for a pointer in the right direction here. > > My software periodically detects files on a FTP Server and downloads them. > This works fine for some time but quite randomly, out of a suddin this > loop starts to hang indefinitely until manually killed and restarted by > the Administrator. > > I narrowed it down so far that I can say that the FTPClient.listFiles() > method hangs and never returns. Here is what the ftp communication log > says on a normal run: > > 2012-09-04T12:41:01.130Z DEBUG [location.FtpLocation.protocolCommandSent] > Veribox A-Dateien: --> NOOP > 2012-09-04T12:41:01.132Z DEBUG > [location.FtpLocation.protocolReplyReceived] Veribox A-Dateien: <-- 200 > Command okay. > 2012-09-04T12:41:01.132Z DEBUG [location.FtpLocation.protocolCommandSent] > Veribox A-Dateien: --> PASV > 2012-09-04T12:41:01.140Z DEBUG > [location.FtpLocation.protocolReplyReceived] Veribox A-Dateien: <-- 227 > Entering Passive Mode (172,35,1,12,7,70 > ) > 2012-09-04T12:41:01.141Z DEBUG [location.FtpLocation.protocolCommandSent] > Veribox A-Dateien: --> LIST * > 2012-09-04T12:41:01.146Z DEBUG > [location.FtpLocation.protocolReplyReceived] Veribox A-Dateien: <-- 150 > Opening ASCII mode data connection for > /bin/ls. > 2012-09-04T12:41:01.186Z DEBUG > [location.FtpLocation.protocolReplyReceived] Veribox A-Dateien: <-- 226 > Transfer complete. 117 bytes transferre > d. 7,14 KB/sec. > > And here is what it says the moment it hangs up: > > 2012-09-04T12:41:51.196Z DEBUG [location.FtpLocation.protocolCommandSent] > Veribox A-Dateien: --> NOOP > 2012-09-04T12:41:51.197Z DEBUG > [location.FtpLocation.protocolReplyReceived] Veribox A-Dateien: <-- 200 > Command okay. > 2012-09-04T12:41:51.198Z DEBUG [location.FtpLocation.protocolCommandSent] > Veribox A-Dateien: --> PASV > 2012-09-04T12:41:51.204Z DEBUG > [location.FtpLocation.protocolReplyReceived] Veribox A-Dateien: <-- 227 > Entering Passive Mode (172,35,1,12,7,71 > ) > 2012-09-04T12:41:51.205Z DEBUG [location.FtpLocation.protocolCommandSent] > Veribox A-Dateien: --> LIST * > 2012-09-04T12:41:51.211Z DEBUG > [location.FtpLocation.protocolReplyReceived] Veribox A-Dateien: <-- 150 > Opening ASCII mode data connection for > /bin/ls. > > As you can see, the server answers that it's opening an ascii mode data > connection but then nothing seems to happen. > > This is what netstat -np says: > tcp 91 0 172.30.3.21:39009 172.35.1.12:2730 CLOSE_WAIT > 24094/java > tcp 0 0 172.30.3.21:45273 172.35.1.12:1863 ESTABLISHED > 24094/java > tcp 0 0 172.30.3.21:56584 172.35.1.12:2299 ESTABLISHED > 24094/java > tcp 0 0 172.30.3.21:53582 172.35.1.12:2730 ESTABLISHED > 24094/java > tcp 0 0 172.30.3.21:57945 172.35.1.12:2730 ESTABLISHED > 24094/java > tcp 95 0 172.30.3.21:39010 172.35.1.12:2730 CLOSE_WAIT > 24094/java > > 2730 is the control port of the ftp server, 2299, 1863 are data > connections. Note the non-empty Send-Q for the CLOSE_WAIT connections. > > The issue I have here seems to be relatively independent of everything I > can come up with. > We have this problem in both linux (SuSE 11.4 64bit) and Windows XP, The > FTP server being once a Serv-U under Windows 2003 Standard and vsftp under > linux. The java virtual machine is openjdk under linux and sun java 6 > under windows. As far as I can see, no proxies or firewalls are in the way > on either of the customers systems. I tested with both commons-net 2.0 and > 3.1 with no difference in result. > > Did anyone on this list ever encounter an issue like this before and is > there a way to circumvent this stalling of the listFiles() call?
If you can provide a sample program that reproduces the problem, then please raise a JIRA issue and attach the code and sample output from the run. Make sure you enable command logging. > Kind regards, > Johannes Frank > -------------------------------------------------------------------------------------------------------------------------------------------- > Johannes Frank - KISTERS AG - Charlottenburger Allee 5 - 52068 Aachen - > Germany > Handelsregister Aachen, HRB-Nr. 7838 | Vorstand: Klaus Kisters, Hanns Kisters > | Aufsichtsratsvorsitzender: Dr. Thomas Klevers > Phone: +49 241 9671 -0 | Fax: +49 241 9671 -555 | E-Mail: > johannes.fr...@kisters.de | WWW: > -------------------------------------------------------------------------------------------------------------------------------------------- > This e-mail may contain confidential and/or privileged information. If you > are not the intended recipient (or have received this e-mail in error) please > notify the sender immediately and destroy this e-mail. Any unauthorised > copying, disclosure or distribution of the material in this e-mail is > strictly forbidden. --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@commons.apache.org For additional commands, e-mail: user-h...@commons.apache.org
