mongodb - Starting Mongod Fails Repetitively -

macos:

i try mongodb running... when type in mongod happening:

exception in initandlisten: 98 unable create/open lock file: /data/db/mongod.lock errno:13 permission denied 

is enough determine what's wrong? or should post the whole error message?

so have solution:

i went terminal , run chmod 777 /data/db.

now mongod works , mongo works well.