Guide originally posted here: TuxCoder
I preformed this install on a server running Ubuntu 11.04. All commands should be executed by the root user or by using sudo.
First, install the needed TFTP packages.
sudo apt-get update && sudo apt-get install tftp-hpa tftpd-hpa
The default location for for TFTP files is /var/lib/tftpboot. You can set a different location later if you'd like, but you must chmod and chown the directory you choose.
sudo mkdir /var/lib/tftpboot
sudo chown nobody.nogroup /var/lib/tftpboot
sudo chmod 777 /var/lib/tftpboot
Edit the TFTP server configuration file to put the service in daemon mode and set a custom directory you may have chosen above.
sudo nano /etc/default/tftpd-hpa
Edit the file to your liking.
#Defaults for tftpd-hpa
OPTIONS="-l -s /var/lib/tftpboot"
Start the TFTP server.
sudo /etc/init.d/tftpd-hpa start
To ensure the service started, run this command:
netstat -a |grep tftp
The Output should look something like this:
$ netstat -a | grep tftp
udp 0 0 *:tftp *:*
Copy any files you need to share over TFTP to /var/lib/tftpboot or the directory you chose and you're good to go!