nanog mailing list archives
Re: PPP multilink help
From: Anton Kapela <tkapela () gmail com>
Date: Mon, 11 May 2009 12:02:40 -0400
Gents, On Mon, May 11, 2009 at 10:54 AM, Dan White <dwhite () olp net> wrote:
Andrey Gordon wrote:
[snip]
When I transfer a large file over FTP (or CIFS, or anything else), I'd expect it to max out either one or both T1, but instead utilization on the T1s is hoovering at 70% on both and sometimes MLPPP link utilization even drops below 50%. What am I'm not gettting here?
Sounds like the TCP window is either set 'small' or TCP window scaling either isn't enabled or isn't scaling to your bandwidth/delay product (for the hosts in question). Since FTP is a 'stream' based transport of file data (like http), you should see this scale to nearly all of or most of your links (assuming TCP isn't your issue). Additionally, when using CIFS, SMB, TFTP, NFS, and other command->acknowledgment style protocols over wide-area links (which aren't stream-based operations, but rather iterative operations on blocks or parts of a file), you likely will never observe a single transfer filling up the links. -Tk
Current thread:
- PPP multilink help Andrey Gordon (May 11)
- Re: PPP multilink help Dan White (May 11)
- Re: PPP multilink help Anton Kapela (May 11)
- Re: PPP multilink help Rodney Dunn (May 11)
- RE: PPP multilink help Matthew Huff (May 11)
- Re: PPP multilink help Andrey Gordon (May 11)
- Re: PPP multilink help Rodney Dunn (May 11)
- RE: PPP multilink help Matthew Huff (May 11)
- Re: PPP multilink help Dan White (May 11)