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

You cannot create a /data/ directory. That is reserved for the APFS filesystem. Check Bombich’s blog about this issue.

Answer 2

So, with macOS Catalina Apple created a new Volume for security purposes. If you’re on macOS Catalina, you'll need to create the /data/db folder in System/Volumes/Data.

Follow these commands

1. sudo mkdir -p /System/Volumes/Data/data/db
2. sudo chown -R id -un /System/Volumes/Data/data/db

Start MongoDB

3. brew services run mongodb-community

4. Enjoy

Answer 3

I am at a loss why Apple did that.. So now, we can not have any root level directory other than theirs ? This just doesn't make any sense and people creating with root privileges those folders know what they are doing

Answer 4

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"