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

If you have Mac and updated to Catalina than the root folder is no longer writable.

I just changed the directory somewhere else.

Been using this command for now

mongod --dbpath=/Users/user/data/db

Answer 2

I create a gist with simple steps to install and run mongodb on catalina

# install homebrew (https://brew.sh/) and run the following commands
sudo chown -R $(whoami) $(brew --prefix)/*
brew tap mongodb/brew
brew install mongodb-community@4.2

## --- aliases to set in your zshrc file

# open your zshrc file
open ~/.zshrc
# copy and paste shorcuts in the end of the file
alias mongod='brew services run mongodb-community'
alias mongod-start='brew services start mongodb-community' #will start MongoDB automatically when you login into your Macbook
alias mongod-status='brew services list'
alias mongod-stop='brew services stop mongodb-community'

# restart your terminal
# type mongod in your terminal for run service & mongod-stop for finish it
# test your mongodb connection with
mongo
show dbs

https://gist.github.com/sturmenta/cf19baa91b1d79d8ae2b305fb7e1f799

Answer 3

This is what worked for me as I was undergoing a Udemy course: 1. Install HomeBrew by typing this into your terminal

/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

2. Move your old /data/db folder (if you want to backup your current dbs) into a non root folder and proceed with the next step

3. Run in Terminal a) brew uninstall mongodb b) If needed run brew uninstall --force mongodb c) brew tap mongodb/brew d) brew install mongodb-community e) brew services start mongodb/brew/mongodb-community

4. All you need now is to run mongo in the Terminal and you'll see the mongo shell symbol >.

Please let me know if this works ;) It took me almost 2 hours to figure it out, based on this article: https://apple.stackexchange.com/questions/362883/mongodb-doesnt-work-after-update-to-macos-catalina-10-15

Cheers, Radu

Answer 4

If you are on mac and facing the issue then below command is useful, whoami variable will get the current user

mongod --dbpath=/Users/$(whoami)/data/db

Answer 5

from the official docs https://docs.mongodb.com/manual/tutorial/install-mongodb-on-os-x/

install homebrew and run the following commands

sudo chown -R $(whoami) $(brew --prefix)/*

then

brew tap mongodb/brew

then

brew install mongodb-community@4.2

and

brew services start mongodb-community

or

mongod --config /usr/local/etc/mongod.conf

then

ps aux | grep -v grep | grep mongod

and

mongo

to verify you can run show dbs in the mongo shell

Answer 6

To make a permanent change of the path of mongod db folder.

Following these docs they say roughly this. If mongod is started with brew services:

$ brew services start mongodb-community@4.2

It will use config file at path /usr/local/etc/mongod.conf

---

To fix this, edit the config file:

$ vim /usr/local/etc/mongod.conf

And change the dbPath e.g. to your home directory like this:

systemLog:
  destination: file
  path: /usr/local/var/log/mongodb/mongo.log
  logAppend: true
storage:
  dbPath: /Users/<username>/data/db
net:
  bindIp: 127.0.0.1 

Save the file and restart mongod with brew:

$ brew services restart mongodb-community@4.2