Want to protect your cyber security and still get fast solutions? Ask a secure question today.Go Premium

x
?
Solved

slow file download from new 3com switch

Posted on 2005-04-09
5
Medium Priority
?
652 Views
Last Modified: 2011-10-03
We have replace some older planet switches with newer 4200 series 3com switches. There  are 250 workstations and 24 switches roughly half 3 com half planet switches.

when downloading a 50MB file from the server it takes 10 seconds from a planet switch and 100 seconds from a 3 com switch.

All connections are full duplex and 100Mb as far as I know.

Could there be bandwith throttling or something on the new switches that the old switches don't have?
0
Comment
Question by:s_fawcett
5 Comments
 
LVL 11

Expert Comment

by:-Leo-
ID: 13744455
It should not take 100 seconds on 3COM 4200, can you see their configuration ? Is it showing connection at 100 Mbit/sec full duplex (check port LED on the switch) ? Try to connect 2 PC's on the new switches and measure download speed ...
0
 
LVL 5

Expert Comment

by:Genexen
ID: 13744528
How many switches between the server and the workstation?  There may be no problem with your switches - they *could* just be deployed in a piss-poor manner.  Don't forget if you are daisychainging switches your bandwidth is aggregate:  the slowest link determines the highest speed.
0
 

Author Comment

by:s_fawcett
ID: 13744789
from server to 1Gb switch 3com 3812.  output 80Mb/s

Igb fibre link to planet switch   output (100Mb ports) measured at 80 Mb/s

IGb copper link to the 4200 series 3com output  (100Mb ports) briefly at 80 Mb  but falls to a steady 5Mb/s.

This is using a speed check utility on a laptop (100Mb card)  which is used at various points in the server room.

In short not more than 2 switches away from the server.

0
 
LVL 5

Expert Comment

by:Genexen
ID: 13744844
hrm, so based on what you said above, linearly the layout is:

[server]---[3com 3812]---[planet switch]---[3com 4200]---[workstation]

If all your switches are managed, I would query the stp configuration.   Unless you are specifying your root bridge, you may be passing packets to the edge of your switch fabric rather than taking a direct path.  This is only one suggestion.

I would also try spanning the port on the 4200 where you drop to 5Mb/s, and placing a sniffer (Ethereal) on that port.
0
 
LVL 23

Accepted Solution

by:
sciwriter earned 1500 total points
ID: 13746230
"The default state for 10/100/1000 Mbps ports is auto-negotiation
enabled, where the speed, duplex and flow control modes are
negotiated. Alternatively, auto-negotiation can be disabled and the
speed, duplex and flow control setting can be manually configured."

Page 16 of the manual.  I would suggest the manual configuration,
get it off autoconfiguration, that sounds like your problem....

http://support.3com.com/infodeli/tools/switches/3824/dua1740-0aaa01.pdf
0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article is in regards to the Cisco QSFP-4SFP10G-CU1M cables, which are designed to uplink/downlink 40GB ports to 10GB SFP ports. I recently experienced this and found very little configuration documentation on how these are supposed to be confi…
This article will show how Aten was able to supply easy management and control for Artear's video walls and wide range display configurations of their newsroom.
Get a first impression of how PRTG looks and learn how it works.   This video is a short introduction to PRTG, as an initial overview or as a quick start for new PRTG users.
Monitoring a network: how to monitor network services and why? Michael Kulchisky, MCSE, MCSA, MCP, VTSP, VSP, CCSP outlines the philosophy behind service monitoring and why a handshake validation is critical in network monitoring. Software utilized …

564 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question