test Internet bandwidth speed

['chris']

hi

How is the best way to test Internet bandwidth speed?

[Alzhy · Accepted solution]

From One Linux node to another accross the internet or local internet?

UNIX to UNIX (or Linux) I use:

ftp> put "dd if=/dev/zero bs=1024k count =100" /dev/null


That is pure network testing that does not involve Disk I/O

[Alzhy]

Correction:

ftp> put "|dd if=/dev/zero bs=1024k count =100" /dev/null

['chris']

Thx a lot, but can you pls give some more details what exactly does this command do?

[Alzhy]

It reads from the zero device at a block size of 1MB up to 1000 times for a total of ~ 1GB (1024KB x 1000). Then the stream is written on the destination Linux or UNIX system to a NULL device -- so no DIsk I.O is involved.

I've always used this trick to see if the bandwidth I should be seeing is available -- i.e. to find out if my GigE or 10GbE pipe is working according to spec.

[rick jones]

It does leave one at the mercy of FTP's selection of socket buffer and thus TCP window size, which can be quite important for "Internet" bandwidth.

[Alan_152]

dslreports.com

['chris']

> Correction:

ftp> put "|dd if=/dev/zero bs=1024k count =100" /dev/null

I've tried on unix and linux and get this error:

unix sco:

ftp> put "|dd if=/dev/zero bs=1024k count =100" /dev/null
local: |dd if=/dev/zero bs=1024k count =100 remote: /dev/null
dd: bad arg: "count"
200 PORT command successful
550 /dev/null: No such file or directory

linux debian:

ftp> put "|dd if=/dev/zero bs=1024k count =100" /dev/null
local: |dd if=/dev/zero bs=1024k count =100 remote: /dev/null
dd: unrecognized operand `count'
Try `dd --help' for more information.
200 PORT command successful
550 /dev/null: No such file or directory

[Dennis Handly]

>dd: bad arg: "count"

Cutting from your command, Alzhy and you shouldn't have a space before the "=".

[Reiner Rottmann]

This may also come handy:
http://bwmon.sourceforge.net/