Syncing multiple folders with rsync

In the past I used to keep two folders on my laptop synced with their respective equivalents on an external hard disk. I used Grsync and ran it twice whenever I wanted to sync. Now I'm using a more complex distribution of my files and would like to sync more than two folders with their respective external equivalents.

In other words, I want to to sync (one way) say:

/home/user/Folder1 with /extHDD/Folder1
/home/user/Folder2 with /extHDD/Folder2
etc

Instead of running grsync multiple times, is there a simpler way to

1. Specify a series of source and destination directories
2. Have the possibility to check what would be changed before actually syncing.

I'm open to CLI or GUI methods.

1 Answer

Rsync (more) (examples) itself is a viable option, which

1. allows you to specify a series of source and destination directories, and
2. due to its --dry-run option which shows you what will happen without actually moving files (as described in point 9 here).