Read-only file system when attempting mkdir /data/db on Mac

Question

I am trying to create a new folder in the main directory

Tried all kinds of examples

sudo mkdir /data/db

sudo mkdir -p /data/db<

Answer 1

To add on to what David Buck wrote here, first you have to actually make the directory. You can do that with:

sudo mkdir /System/Volumes/Data/data/db

If you're getting this error:

"Error parsing command line: unrecognised option '--dbpath/System/Volumes/Data/data/db' try 'mongod --help' for more information"

after creating the alias, it's just because David Buck (while making a really helpful comment) missed a space in his answer.

To fix this, type

unalias mongod

and then type

alias mongod="sudo mongod --dbpath /System/Volumes/Data/data/db"