I recently purchased a new computer and needed to transfer files from the old computer to the new one. Tried a USB drive, no luck. Tried copying files over the network via the macOS Finder, but the sheer number of files (~500,000) made this an exercise in futility.

Googling for a better solution led me to rsync, a highly efficient file transfer and synchronization tool. rsync is open source and comes pre-installed on macOS. After talking with friends, this is the utility they use. Probably should have asked them before trying to figure it out myself.

rsync has a simple API:

rsync [OPTIONS] SOURCE DESTINATION

There are a ton of options and I wasn't too sure what to select. I wanted to preserve symbolic links and last modified datetimes. After looking thru the man pages and StackOverflow, I settled on the following:

-v              verbose
-h              human-readable
-a              archive mode
-H              preserve hard links
-E              copy extended attributes, resource forks
--progress      show progress during transfer

Next I needed to find a way to specific a remote machine in the terminal. The syntax for this is {username}@[machine-name]:/path/to/dir.

Putting it together with some error logging gives us the following:

$ rsync -vhaHE --progress alysivji@MacSivProOG.local:/Users/alysivji/Documents/siv-dev /Users/alysivji/shared/siv-dev 2> errors.log

...

sent 12.02M bytes  received 21.36G bytes  6.96M bytes/sec
total size is 21.29G  speedup is 1.00

That was easy. What a great utility! More rsync goodness.

I did a short retro after figuring out how to transfer files from one machine to the next:

What went well

• Was able to transfer files from old computer to new computer

What did not go well

• trying to transfer files using USB and WiFi

What to improve going forward

• ask friends for tips and tricks before getting started
• always look for a UNIX first solution. Somebody has already solved my problem, I just don't know it