Using netcat to copy files between servers

On target: "nc -l 4000 | tar xvf -" On source: "tar -cf - . | nc target_ip 4000"

It bypasses encryption overhead of SSH and depending on configuration can be significantly faster. It's recommended to use only in trusted networks.

By: tiagofischer

2009-06-30 19:36:19

tar nc

1 Alternatives + Submit Alt

Using netcat and lz4c to copy files between servers

Adds high-performance, lightweight lz4 compression to speed the transfer of files over a trusted network link. Using (insecure) netcat results in a much faster transfer than using a ssh tunnel because of the lack of overhead. Also, LZ4 is as fast or faster than LZ0, much faster than gzip or LZMA, an in a worst-case scenario, incompressible data gets increased by 0.4% in size. Using LZMA or gzip compressors makes more sense in cases where the network link is the bottleneck, whereas LZ4 makes more sense if CPU time is more of a bottleneck.
This is sample output - yours may be different.
0

On target: "nc -l 4000 | lz4c -d - | tar xvf -" On source: "tar -cf - . | lz4c | nc target_ip 4000"

baitisj · 2014-08-02 05:09:30 7

What Others Think

thats what scp is for.

linuxrawkstar · 805 weeks and 3 days ago

@linuxrawkstar not when you want to avoid the overhead of an ssh connection and it's encryption as the original poster said. I' ve even set the cipher to blowfish (the fastest and "least secure") and there is fair overhead cpu-wise, so much so that the CPU essentially limits the transfer speed. scp offers security, not speed.

bwoodacre · 805 weeks and 2 days ago

That is, in machines that aren't CPU "fast" by today's standards.

bwoodacre · 805 weeks and 2 days ago

Rebekah gave up on the Rhode Island set forever mention

yeoyeo · 172 weeks and 5 days ago

rahimhh21 · 117 weeks and 4 days ago

Perfecthomepugs · 109 weeks and 3 days ago

pugpuppies95 · 71 weeks and 3 days ago

donperi1 · 64 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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