*BSD News Article 92082


Return to BSD News archive

Path: euryale.cc.adfa.oz.au!newshost.carno.net.au!harbinger.cc.monash.edu.au!news.cs.su.oz.au!inferno.mpx.com.au!nsw1.news.telstra.net!news.telstra.net!news-out.internetmci.com!newsfeed.internetmci.com!newsfeed.direct.ca!super.zippo.com!zdc!news.pbi.net!news.mathworks.com!news.maxwell.syr.edu!news.bc.net!unixg.ubc.ca!van-bc!n1van.istar!van.istar!west.istar!news-w.ans.net!newsfeeds.ans.net!lantana.singnet.com.sg!newsfeed.singnet.com.sg!chenab.lums.edu.pk!chenab.lums.edu.pk!not-for-mail
From: aslam@lums.edu.pk (Sohail Aslam)
Newsgroups: comp.unix.bsd.freebsd.misc
Subject: Poor ftp performance between FreeBSD machines connected via Cisco Switch
Date: 25 Mar 1997 18:09:20 +0500
Organization: Lahore University of Management Sciences (LUMS)
Lines: 36
Message-ID: <5h8iq0$iso@chenab.lums.edu.pk>
NNTP-Posting-Host: chenab.lums.edu.pk
Xref: euryale.cc.adfa.oz.au comp.unix.bsd.freebsd.misc:37845

I am cross posting this here; the original posting was on the Cisco newsgroup.
I hope someone with FreeBSD has similar installation.

We recently replaced an old Kalpana switch with a 14 port (2+12) Cisco 2900
switch (Catalyst 2900). Two ports are 100Mbps Ethernet half/full duplex while
12 are autosensing 10/100 half/full duplex ethernet. We connected a FreeBSD
2.2 machine (named "ravi") with SMC Etherpower card (10/100 full/half duplex) 
directly to one port and a bay hub with Fast Ethernet ports on another port 
of the 2900.  The Bay hub has 3 FreeBSD machines and windows machines, all 
with SMC Etherpower 10/100 cards. 

When I tried ftp between "ravi" (machine with dedicated port on the 2900)
and any of the 3 FreeBSD machines, the throughput was 10 kilo bytes/sec! 
This came as a surprise. The ftp throughput of the Unix boxes connected 
to the Bay hub at 100Mbps is 1.5 Mbytes/sec. I moved "ravi" from the 
dedicated port on the 2900 to a port on the Bay hub. Now I started getting
1.5 or more Mbytes/sec transfer rate.

I have looked through the Catalyst 2900 User guide; I can't spot an obvious
error on my part. It seems that IP traffic over Fast Ethernet through the
switch is not performing as well as I had anticipated. 

Questions:

1. Is there any particular 2900 setup that will enable good ftp throughput
through the switch over Fast Ethernet?

2. Do I need to tune (or set) some TCP or IP parameter in FreeBSD?

3. What should I monitor on the switch to determine the cause of the problem?

-- 
Sohail Aslam                   
Department of Computer Science, Lahore University of Management Sciences (LUMS)
Lahore, Pakistan    tel: 92-42-572-2670   fax: 92-42-572-2591
email: aslam@lums.edu.pk