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 4

What Others Think

thats what scp is for.

linuxrawkstar · 726 weeks and 1 day 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 · 726 weeks ago

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

bwoodacre · 726 weeks ago

Rebekah gave up on the Rhode Island set forever mention

yeoyeo · 93 weeks and 4 days ago

rahimhh21 · 38 weeks and 3 days ago

Perfecthomepugs · 30 weeks and 2 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?

You must be signed in to comment.

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands

Similar Commands

Emulating netcat -e (netcat-traditional or netcat-openbsd) with the gnu-netcat

create disk copy over the net without temp files

Display information sent by browser

tar a directory and send it to netcat

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

» all commands
» commands with 3 up-votes (commandlinefu3)
» commands with 10 up-votes (commandlinefu10)