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Test network speed without wasting disk

Terminal - Test network speed without wasting disk
dd if=/dev/zero bs=4096 count=1048576 | ssh [email protected] 'cat > /dev/null'
2010-06-08 18:49:51
User: atoponce
Functions: dd ssh
Test network speed without wasting disk

The above command will send 4GB of data from one host to the next over the network, without consuming any unnecessary disk on either the client nor the host. This is a quick and dirty way to benchmark network speed without wasting any time or disk space.

Of course, change the byte size and count as necessary.

This command also doesn't rely on any extra 3rd party utilities, as dd, ssh, cat, /dev/zero and /dev/null are installed on all major Unix-like operating systems.


There is 1 alternative - vote for the best!

Terminal - Alternatives

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What others think

This will compress really well with ssh (/dev/zero is the same byte over and over). For a better test replace /dev/zero with /dev/urandom,

Comment by sdadh01 320 weeks ago

The SSH connection is adding overhead with encryption, thus the reason to use /dev/zero to level the playing field, otherwise, your bandwidth will be considerably less.

Comment by atoponce 320 weeks ago

Or you could use netcat and use /dev/urandom. This way you don't have the overhead of compression and use a more realistic approach to test your network.

dd if=/dev/urandom bs=4096 count=1048576 | nc host.tld 1234

and on host.tld you should start netcat with the 'listen' parameter

nc -l -p 1234 | dd of=/dev/null

Actually, if you really wanna test your network you should go the iperf or netperf way (and use UDP or TCP, depending on how you wanna test it).

Comment by paragao 319 weeks and 5 days ago

Right. This isn't meant to be an accurate network bandwidth benchmarking tool. This is useful for nothing more than a rough estimate, and it doesn't rely on any external 3rd party tool, and it's cross platform, which was the goal.

Comment by atoponce 319 weeks and 5 days ago

this command is helpful for a 'rough estimation' but i would add the ssh '-c arcfour' option.

Comment by cp 316 weeks and 2 days ago

Your point of view

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