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

Question

I am trying to create a new folder in the root directory.

I tried all kinds of examples.

sudo mkdir /data/db

sudo mkdir -p /data/db

I keep getting:

mkdir: /data: Read-only file system

https://stackoverflow.com/questions/58283257/mongodb-doesnt-work-on-latest-mac-os10-15 This answers the comments below. — camille, Oct 16 '19 at 18:48
Also see https://stackoverflow.com/questions/58283257/mongodb-doesnt-work-on-latest-mac-os10-15 — Adam Zerner, Oct 23 '19 at 19:01
[Techno Peace](https://stackoverflow.com/users/12741466) posted an [Answer](https://stackoverflow.com/a/66233947) saying "Due to Catalina OS update, it changed. Follow this link to achieve: https://docs.mongodb.com/manual/tutorial/install-mongodb-on-os-x/" — Scratte, Feb 17 '21 at 17:20

score 222 · Accepted Answer · edited Apr 18 '22 at 02:32

222

If you have a Mac and updated to Catalina or more recent version, then 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

edited Apr 18 '22 at 02:32

Ebenezer Nikabou

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answered Oct 16 '19 at 00:06

jalapina

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Is there a way to make it permanent? I have to type it every time I start the MongoDB server! – AV Paul Nov 20 '19 at 08:54
2

@AVPaul Maybe not the best solution, but you could make an alias that refers to your path. – DjangoBlockchain Dec 10 '19 at 13:34
Im actually getting Data directory /Users/user/data/db not found., terminating. Even though I created the folder – Jeff Goes Jan 04 '20 at 20:24
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@JeffGoes I am assuming you did not replace the user with the actual name. – Aman Jan 12 '20 at 23:44
Despite this working (and solving my problem), it seems hacky – Alex L Feb 14 '20 at 19:57
3

@AlexL It's working for me too. But do I have to type mongod --dbpath=/Users/my_USER_name/data/db everytime I want to run my dev mongo db? Because next time when I run mongod, it is saying /data/db not found – Shoeb Mirza Feb 28 '20 at 07:31
7

you can make it permanent by setting the dbPath in mongoDB config file if you're using mac it's under /usr/local/etc/mongod.conf. then add the following : "storage: dbPath: path to your db directory" – Samoox Aug 05 '20 at 11:56
4

I forgot how annoying updating OS X is no wonder I always resist it – Anthony Aug 19 '20 at 08:44
It might be worth noting that `/usr` is a hidden folder. To 'see' it, press cmd + shift + . (dot). That being sad, I don't seem to have a folder `etc` in `/usr/local/`. Now what? – Reinier68 Oct 13 '20 at 19:56
This answer is a work around but does not seem to be what the question is asking. – Brianhenry Dec 15 '22 at 10:13

score 107 · Answer 2 · edited Nov 24 '19 at 03:50

107

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

edited Nov 24 '19 at 03:50

aug2uag

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answered Nov 16 '19 at 21:26

Will Abule

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brew services start mongodb-community => Error: Formula `mongodb-community` is not installed. You have to launched: brew services start mongodb/brew/mongodb-community@4.2 – Andresse Njeungoue Dec 04 '20 at 00:49
1

I wish I could click upvote button more than once. – Syeda Aimen Batool Dec 30 '21 at 05:18

score 58 · Answer 3 · edited Aug 22 '20 at 08:42

58

With the new macOS Catalina update, the folder /data/db becomes read-only, you cannot modify it. Follow this procedure to create a DB in another folder:

Change mongod directory :

sudo mongod --dbpath /System/Volumes/Data/data/db
Give it an alias to use it as mongod:

alias mongod="sudo mongod --dbpath /System/Volumes/Data/data/db"
Just type mongod in your terminal, it should work.

Extra => If you need to give it current user rights, use this line of code :

sudo chown -R $(whoami) /System/Volumes/Data/data/db

(Just for info -> $(whoami) is just a variable that returns your current user)

edited Aug 22 '20 at 08:42

Mohit kumar

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answered Apr 25 '20 at 09:58

Eugène Beliaev

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I did this before step 1: `sudo mkdir -p /System/Volumes/Data/data/db` && ```sudo chown -R `id -un` /System/Volumes/Data/data/db```. Not sure if these folders exist already but combined @xgqfrms's answer with this one. Thanks so much for this, was driving me crazy. – twknab Dec 06 '20 at 07:20
This is perfect! – Jignesh Feb 19 '21 at 14:09
even if I change ownership of `/System/Volumes/Data/data/db` I still need to provide password everytime I run the `mongod` command – Bn.F76 Mar 20 '21 at 00:40
I've tried several solution, the only one that worked for me. Thank you. – Menai Ala Eddine - Aladdin Apr 25 '21 at 02:14
i struggled for 2 days.now its working for me ..appreciate – Shekh Firoz Alam Aug 30 '21 at 00:49
it is working in mac m1 chip – Ravi Kumar Jul 22 '23 at 14:08

xgqfrms · Answer 4 · 2020-07-09T15:29:50.010

You can't create a folder on the root directory on Mac Catalina anymore!

https://www.apple.com/macos/catalina/features/

Dedicated system volume

macOS Catalina runs in a dedicated, read-only system volume — which means it is completely separate from all other data and helps improve the reliability of macOS.

# macOS Catalina, mkdir path
$ sudo mkdir -p /System/Volumes/Data/data/db

# give permissions
$ sudo chown -R `id -un` /System/Volumes/Data/data/db

# macOS 10.14.x -
$ sudo mkdir -p /data/db

# macOS 10.15.x +
$ sudo mkdir -p /System/Volumes/Data/data/db

refs

https://discussions.apple.com/thread/250720711

https://zellwk.com/blog/install-mongodb/

https://www.youtube.com/watch?v=DX15WbKidXY

score 12 · Answer 5 · answered Feb 19 '20 at 11:13

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

this did not work for me, mongo is still looking in /data/db — Xen_mar, May 16 '20 at 13:17
@Xen_mar were you trying to run mongod after editing the file? Apparently mongod is already run by brew services start — J.E.C., Sep 11 '20 at 07:26

score 7 · Answer 6 · answered Mar 18 '20 at 13:08

7

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

answered Mar 18 '20 at 13:08

Anjum....

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score 7 · Answer 7 · answered Jun 20 '20 at 21:45

7

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

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

Start MongoDB

brew services run mongodb-community
Enjoy

answered Jun 20 '20 at 21:45

`brew services run mongodb-community` gave me `Error: No available formula with the name "mongodb-community".` – JoeTidee Sep 02 '21 at 00:18

score 7 · Answer 8 · answered Nov 05 '20 at 20:03

7

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

answered Nov 05 '20 at 20:03

Laurent-Philippe Albou

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typical apple: helicopter-parenting their users – spb May 07 '23 at 15:57

score 5 · Answer 9 · edited Feb 25 '20 at 19:50

5

I did this:

mkdir -p usr/local/var/mongodb/data/db

since the new path that is "usr/local/var/mongodb".

edited Feb 25 '20 at 19:50

Tiago Martins Peres

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answered Feb 25 '20 at 19:33

franfonse

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score 5 · Answer 10 · edited Jul 27 '20 at 02:21

5

Default Paths for the mongodb-community Formula

In addition to installing the MongoDB server and tool binaries, the mongodb-community formula creates:

a configuration file: /usr/local/etc/mongod.conf
a log directory path: /usr/local/var/log/mongodb
a data directory path: /usr/local/var/mongodb

then it worked for me:

mkdir -p usr/local/var/mongodb/data/db

edited Jul 27 '20 at 02:21

Tamil Selvan C

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answered Jul 27 '20 at 00:28

shivkanth patil

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score 4 · Answer 11 · answered Oct 18 '19 at 09:11

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)"

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
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
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

score 4 · Answer 12 · answered Jul 10 '20 at 16:02

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"

It wasn't me... credit should go to Eugène Beliaev. I just edited their answer for formatting... — David Buck, Jul 10 '20 at 18:37

jvarela · Answer 13 · 2019-12-12T09:14:14.060

1

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

edited Dec 12 '19 at 09:14

answered Sep 21 '19 at 06:41

jvarela

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So, could this read-only file issue be solved? I have the same problem – Zainab Hammami Oct 13 '19 at 12:29
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No, you need to use another name for your directory. A possible solution could be to create the data directory inside another directory which is allowed as a root directory. – jvarela Oct 13 '19 at 12:47

score 1 · Answer 14 · edited Nov 29 '19 at 12:40

1

With macOS Catalina, you can no longer store files or data in the read-only system volume, nor can you write to the "root" directory ( / ) from the command line, such as with Terminal.

edited Nov 29 '19 at 12:40

user803422

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answered Nov 29 '19 at 09:23

Ümit Ünver

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score 1 · Answer 15 · answered Apr 13 '20 at 15:23

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

RobKohr · Answer 16 · 2020-02-05T15:44:17.700

0

Mac version Catalina made the root folder is no longer writable.

Brew has an updated version of mongodb to use a new path (which it creates itself), /usr/local/var/mongodb and following these instructions will fix the issue:

Guide to installing updated mongodb-community-edition

brew install mongodb-community@VERSION where the first VERSION with the fix is 4.2

edited Feb 05 '20 at 15:44

answered Feb 05 '20 at 15:38

RobKohr

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

16 Answers16

You can't create a folder on the root directory on Mac Catalina anymore!

Dedicated system volume

refs

Linked

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