topic Re: Slow FTP transfers in Operating System - HP-UX

Slow FTP transfers

David McMullen_1 — Thu, 21 Dec 2000 17:39:56 GMT

I am trying to FTP a 22mb file to a machine on our lan. To put this file on the remote host, it takes about 30 minutes. To get this file from the same remote host to the local host it takes about 30 seconds. The LAN is a mixture of switched 10 and 100Mb ethernet. Any help is appreciated!

Re: Slow FTP transfers

David McMullen_1 — Thu, 21 Dec 2000 18:28:02 GMT

It was a duplexing issue. I changed the switch from Full duplex to half duplex. BAM!

Guess I should have read some previous postings first!

Re: Slow FTP transfers

Mike McKinlay — Thu, 21 Dec 2000 18:39:59 GMT

Darn! I saw the subject heading and knew right away it was either going to be a speed or duplexing problem on the NIC of the system or on a switching hub or other interconnect.

Missed out on some cheesy points, I guess ... oh well.

The lesson here is when your NIC or switching hub setting offers "Auto-sense" the speed and duplex options: don't trust it. If you know you want to use 100BT Full Duplex, set it on both sides of the connection. Don't forget your interconnect devices! The auto-sensing gets caught in negotiations between the systems and slows the traffic tremendously.

It's similar to why your 56K modem will only connect to your ISP at 28.8 ...