how to run a task automatic when system boot

Sometimes we need run some commands automatic when system boot up.

We can put the command or script into /etc/rc.local
like:
vi /etc/rc.local
add command line into file
mount --bind /var/www/html/ /home/ftpuser


This will mount web base dir to ftp base dir automatic when system startup.

And don’t forget to give rc.local execute permission.
chmod +x /etc/rc.local