I have an external drive connected to my iMac via Thunderbolt. I also have a NAS connected to my router via ethernet cable. I want to compare the folders and files on these two drives and see the differences (e.g., items on one drive, but not on the other drive). Anyone know of software that will do this? Thx
iMac, OS X Yosemite (10.10)
What kind of files are they? You can use the Terminal command "diff" to compare files, or you can use Apple's FileMerge program, though these are best for comparing the character structure of text/ascii files. Alternatively, you can run checksums using md5 and sha in the Terminal (though there are several programs that implement these for comparing two specified files).
As for comparing the specific folders, you can use a program like Chronosync, or if you are familiar with the Terminal then use "rsync" to run a dry-run syncing routine to see what files it finds are different between two specified locations.
Thanks. They are mostly video and audio files: mp3, aac, m4v, etc.
I neglected to mention this, but I only need to compare the folder / file metadata - folder name, file name, last modified date, etc. If the software can flag metadata differences, that's good enough for me. I do not need / want to "look inside" a file to see if the data is the same.
Thanks
Your best bet for that is a syncing program that can perform a dry run and show you what files differ in each location. OS X comes with the "rsync" terminal command, which can be used if you're savvy with the Terminal, otherwise you can search around for a synchronizing tool that will do this.
This question was recently discussed and a couple of possibilities suggested here:
how to compare two folders and copy the differences
C.
You can read more of course in Terminal, copy and paste:
man rsync | more
How to compare files on two drives?
