[noleli2]

Hey all, I have two external drives I'd like to keep in sync. One is a desktop drive, one is portable. I'd prefer to not have one be the "master", because I'd like to use my portable while I'm at hope/out and the desktop one while I'm at work. (I try not to bring the portable drive to work too often because I like to keep backups offsite.)

Once in a while, though, I need to do a two-way sync between the drives. I tried arRsync, a Cocoa front-end to rysnc. After taking close to an hour, it doesn't seem to do anything at all. The files on one drive that are not on the other are not copied over. I tell it to do a bidirectional synchronize.

Is rsync not the tool I need? Am I setting up arRsync wrong? Thanks!

[Brad]

rsync can take a long time to get started, especially if you're syncing a large directory structure like a whole drive. rsync walks the whole tree and checksums files *before* it starts transferring. That's why it can seem to be nothing for a long time before actually springing to life.

You might want to try a sync overnight.

Alternatively, look into Carbon Copy Cloner, but I don't know if/how it resolves conflicts if the destination is newer than the source. CCC can also take a really long time to get going. The last time I used it on a drive, it took nearly a full 24 hour day.

[FFL]

SuperDuper's Smart Update feature works better for this type of thing than CCC.

You get even more control over potential version conflicts with ChronoSync.

This article
http://www.cultofmac.com/how-and-why...ve-macrx/48861
offers some detailed information.

[noleli2]

Thanks, Brad and FFL. I use SuperDuper (with Smart Update) regularly for my clones of my internal drive. The issue Brad alluded to is that I need to do a two-way sync. ChronoSync would probably do what I need it to do, but it's expensive.

arRsync is appealing because it lets me choose whether to do the sync using checksums or just modification dates and sizes. I've been using the latter setting, but there are files on one drive that aren't on the other (and vice versa), so in that situation, I'd at least expect it to copy those files over. I just can't figure out why those don't get copied. (I don't know whether or not modified files are properly synced; I haven't had any modified, just added/removed.)