I am getting the following message
exception in initAndListen std::exception: boost::filesystem::exists: Permission denied: "/vol/mongodb", terminating
in /var/log/mongodb/mongodb.log
ls -al /vol/mongodb gives -
drwxrwxrwx 2 mongodb mongodb 4096 2011-08-07 12:10 ./
When I change the dbpath, back to the default, which is /var/lib/mongodb - it works fine.
How do I solve this?
I had the same problem initially and found it was caused by the mongodb user not having appropriate permissions on the parent directory.
I'd recommend checking /vol to ensure that the mongodb user can at least read files from that directory. May also need execute permissions too, and I suspect this will hold for each subsequent parent directory up to root.
来源：https://stackoverflow.com/questions/6971634/unable-to-change-the-dbpath-in-mongodb-through-mongodb-conf