Is there a reason to use scp
instead of rsync
? I can see no reason for using scp
ever again, rsync
does everything that scp
does, with more safety (can preserve symlinks etc).
6 Answers
scp provides a cp like method to copy files from one machine to a remote machine over a secure SSH connection.
rsync allows you to syncronise remote folders.
They are different programs and both have their uses. scp is always secure, whereas rsync must travel over SSH to be secure.
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13
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4@ckhan, no it can copy without having anything installed in the other side, it'll just be less efficient. May 31, 2012 at 8:40
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2
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2@mikebloch How do you do that? Is it a new feature? Just tried this using version 3.0.9. and it complained it couldn't find
rsync
on the remote.– AlexiosMay 31, 2012 at 10:00 -
1@mikebloch, it has to be installed on the server to do the checksum computations, which can add a lot of cpu load to the server. This is why most large sites don't support it, and why
zsync
was created as an alternative.– psusiMay 31, 2012 at 22:17
One of the main things (which I think no one mentioned) is that if you are transferring large amounts of data or files, and if the transfer is disconnected before completion for any reason, rsync will pick it up where it left off. Whereas scp doesn't.
I use scp if I want to transfer one or couple of files or directories. I go to rsync for multi GB size data.
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3Might be worth adding that the
--partial
flag is useful when transferring large files.rsync
will pick up where it left off within the file rather than starting that file again.– FlupJul 26, 2013 at 15:28 -
As @Flup mentioned rsync won't leave anyt file-in-transit around for you to resume unless you use the --partial option. These files are by default hidden in the target directory. You can use --partial-dir to put all of these files in a single directory. Mar 1, 2016 at 10:56
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Well,
rsync -vP username@host:/path/to/file .
will do this too. See this answer on Stackoverflow Aug 12, 2016 at 18:20
rsync: Transfers deltas(using its Delta Transfer Algorithm) between:
- local and remote hosts
scp: Transfers whole files between:
- local and remote hosts
- remote and remote hosts
Summary: scp
can transfer files between two remote hosts while rsync
doesn't support it.
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rsync can transfer files between two remote hosts. In fact,
rsync a host:b
is equivalent toscp a host:b
. Feb 19, 2017 at 13:34 -
That's what I wrote, rsync can transfer deltas between local and remote hosts but scp is not limited to just that, it can transfer deltas between two remote hosts. @brandizzi Feb 19, 2017 at 14:08
User Chris at Webhosting Talk writes:
rsync
compares the files at each end and transfers only the changed parts of changed files. When you transfer files the first timeo it behaves pretty much likescp
, but for a second transfer, where most files are unchanged, it will push a lot less data thanscp
. It's also a convenient way to restart failed transfers - you just reissue the same command and it will pick up where it left off the time before, whereasscp
will start again from scratch.
Credits to @tomrunia at https://gist.github.com/KartikTalwar/4393116
rsync -aHAXxv --numeric-ids --delete --progress \
-e "ssh -T -c aes128-gcm@openssh.com -o Compression=no -x" \
[source_directory] user@hostname:[target_directory]/
Pay attention to --delete
, don't use it if you want to keep extraneous files in dest dirs
scp
is simpler to use as it takes less arguments. I catch myselv using scp instead of rsync
if I only transfer a single file. Propably I am just to lazy to define an alias to rsync... ;-)
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4Hmmm, why is it so?
rsync a host:b
is equivalent toscp a host:b
, same number of arguments. Apr 9, 2013 at 5:40 -
1@mikebloch Two letters more to type... ;-) In the past I had to supply "-e ssh -a" to get the proper result. Now that "-e ssh" is default this might be a different game.– NilsApr 9, 2013 at 14:44
-u
.cp
andrm
would be considered "harmful" -- and if you define "harmful" as "can screw me over if I do something stupid",rsync
isn't any less harmful.rsync
installed, usingrsync
is (obviously) not even possible.