Is there an advantage to running rsyncd vs. using ssh?

crontab · 03-24-2009, 10:41 AM

Hi, all

Just like the subject says. From what I've been able to tell by searching the forums, there's some (slight?) overhead when using ssh instead of running rsyncd? I'm looking to copy a few gigs worth a night (over gigabit ethernet), that's why I'm concerned enough to ask.

Thanks!

rizwanrafique · 03-24-2009, 12:22 PM

From what I've noticed there is no difference. Not noticeable at least. Probably it differs when dealing with file differences and overwrites.

May be you could copy a smaller data-set and time it using:

Code:

time rsync ...

vindoan · 03-24-2009, 12:33 PM

rsync's can copy differential files. If you have some have files that are replicated on two machines, then using rsync has advantages. Of course, if all the files exist only on the source machine, then rsync loses its advantage.

Check out the rsync tips and tricks http://sial.org/howto/rsync/

Cheers

crontab · 03-24-2009, 12:37 PM

Quote:

Originally Posted by vindoan

rsync's can copy differential files. If you have some have files that are replicated on two machines, then using rsync has advantages. Of course, if all the files exist only on the source machine, then rsync loses its advantage.

Check out the rsync tips and tricks http://sial.org/howto/rsync/

Cheers

Sorry, I didn't realize the ambiguity in my post until just now. Specifically, what I mean is rsync to a server that is running the rsync daemon (on port 873) versus one that isn't (and it uses a listening ssh daemon instead).

vindoan · 03-24-2009, 01:06 PM

The big advantage of running as a daemon comes when you want to constantly maintain a sync between two machines. The caching system of rsync is enabled while running as a daemon. For this reason, busy sites is recommended to run rsync as a daemon. Also, the daemon mode makes it easy to limit the number of concurrent connections.

crontab · 03-24-2009, 01:08 PM

Ah, I see. In this case, it's backups being copied once a night.

If you use the daemon will the connection be encrypted, or is it sent on the clear?

vindoan · 03-24-2009, 01:18 PM

You can setup public keys to share between servers for encryption. The tips and tricks link in my previous posts gives you examples of how to do that.

crontab · 03-24-2009, 01:19 PM

Great, thanks!