Help with CLI commands

[FreeDomBSD]

I have a few TBs of data that I copied from one drive (source folder) onto another (destination folder). Unfortunately not all of the data copied successfully, but 90% of it did. I would like to run a set of commands with which I can compare the source and the destination folder and then copy/recopy the files that do not match the files in the source folder.

I'd appreciate a nudge in the right direction.

 

[kpa]

net/rsync has support for comparing the source and destination files/directories and copying only the changed files or the ones missing from the destination.

 

[FreeDomBSD]

rsync -v /home/user/a /home/user/b


Does this look right for what I'm doing?

Or is it:

rsync -v -r /home/user/a /home/user/b

 

[DutchDaemon]

rsync -av does it right. If you're on a slow WAN, add a -z.

 

[FreeDomBSD]

Thanks DutchDaemon! I'm not on a LAN or WAN. I'm just copying between two external USB drives that are mounted.

 

[kpa]

Make sure you understand the difference between rsync -av /home/user/a /home/user/b and rsync -av /home/user/a/ /home/user/b. The first form would create an extra directory /home/user/b/a that you probably don't want.

 

[FreeDomBSD]

Yea, crap, found that out the hard way @kpa. What is the point of the -a and why not use the the -r switch?

 

[kpa]

The -a flag is a shortcut for flags -rlptgoD, see the manual page for details rsync(1).

 

[FreeDomBSD]

I've read another explanation that just mentioned that -a was archival flag. It have no other explanation. Thanks for the link!