MongoDB: exception in initAndListen: 20 Attempted to create a lock file on a read-only directory: /data/db, terminating

Question

I created /data/db in root directory and ran ./mongod:

[initandlisten] exception in initAndListen: 20 Attempted to create a lock fi         


        

Answer 1

Fix the permissions of /data/db (or /var/lib/mongodb):

sudo chown -R mongodb: /data/db

then restart MongoDB e.g. using

sudo systemctl restart mongod

In case that does not help, check your error message if you are using a data directory different to /var/lib/mongodb. In that case run

sudo chown -R mongodb: 

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