i need to change odoo port from 8069 to 80

i found three solution to solve this problem but both of 2 didn't fix it

the 1st one is

iptables -t nat -A PREROUTING -p tcp --dport 80 -j REDIRECT --to-port 8069

2nd one is iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 80 -j REDIRECT --to-port 8069

3rd one is change my port from odoo-congif file from 8069 to 80

but the tree solution did't fix my problem

which one is right to use in my VPS

i use odoo v 9 and ubuntu v 16.04