Difference between scp and rsync?

Question

Title pretty much says it all. If I have a folder (mydir/) on server1.com, and want to copy it to a parent folder on server2.com, then what is the difference (performance, security, capabilities, etc.) between:

scp mydir/ server2.com:/some/path/

and...

rsync -avz mydir/ [email protected]:/some/path/

Thanks in advance!

Solution

1) Performance

scp will be faster

2) Security

scp is more secure, but if you were to use rsync -avz -e ssh, then rsync would be as secure

3) Capability

rsync can 'sync' the two copies, so lets say if your scp stopped in middle of the transfer for some reason (network issue lets say), you could use rsync to complete the transfer. scp will simply overwrite.

alias scpresume="rsync --partial --progress --rsh=ssh"

rsync can also exclude certain subdirectories/files using the --exclude flag, scp can't do that.

Comments

[Wayne Jhukie]

If this isn't a duplicate of something, it's a valid question

[pnongrata]

Thanks freethinker - what is it that makes scp more secure? SSH? If so, is that why setting rsync's rsh argument to ssh accomplishes the same thing?

[user5249203]

If you repeat the copy, rsync may be faster as it only transfers differences in files. This is it's raison d'être.

[me_and]

AIUI rsync now uses SSH by default, so there's no difference in security. And all the other reports I've seen say rsync will be at least as fast as scp; why do you think scp is quicker?

[Luke Stanley]

So basically most of this answer is out of date or now incorrect?