I just hit reset network settings on my iPhone (9.2.1) because I was unable to make phone calls.
I then noticed that my OSX (10.11.3) lost its internet connection. I immediately checked the keychain (where all wifi passwords are stored) and noticed that all passwords are missing.
I can only assume that resetting the iPhone "network settings" also affected my mac. I assume this occurred through iCloud.
Question
How can I get those Wifi Passwords back?
How can I prevent this from happening again?