I have created a bash script as follows and saved it as /usr/bin/db.sync.sh:

#!/bin/bash



rsync -ar --delete /files/database_backups [email protected]:/users/slyme/Documents/server_backups

I have generated the necessary pair of authentication keys to make this work without the need to enter a password.

When I run the command directly it works (hurrah!).

I have added the following to `/etc/rc.local':

/usr/bin/db.sync.sh >>/files/database_backups/db-sync.log.txt 2>&1

When I restart the machine this script fails and the log file suggests that the process asks for a password which, of course, it doesn't get so it fails. If I run /etc/rc.local from the command line then, sure enough, I get asked for a password and when I enter it the script works.

Anyone got any ideas why the script needs a password when run from rc.local even though it doesn't need a password when run directly?