UNIX for Advanced & Expert Users

Experts,

Please help me. When i try to make a ftp, after issuing PUT <FILENAME> it is taking more than 3 minutes for me to estabilish a DATA connection, after which the actual file transfer starts. Could you please help me in reducing this time delay for establishing data connection during FTP process.

FTP server OS: Sun solaris 5.9

FTP behaves same irrespective of the client used.


Thanks you all in advance

On the FTP server, try ftp to localhost just to eliminate the server itself.

After that, look to the network. Particularly whether the server is connected to a switch and is set to auto-negotiate and has dropped to half-duplex. You don't state whether client and server are on the same LAN or whether there is greater distance, internet, firewalls, routers etc. along the way.

I have had dramatic improvement in ftp performance where there are badly configured routers on the route by making the "ftpd" block size smaller than default (e.g. ftpd -B 32) or lowering the buffer size on the "ftp" client (e.g. ftp -B 1). This is all about avoiding multi-block transfers or jumbo packets where one or more network component cannot cope.

Another thing to check out. Are you trying to PUT a file to an automounted or NFS subdirectory.