Synology documentation sucks big time! It usually only states the blindingly obvious missing off any useful or helpful information.
This post will run through the harder parts of setting up DNS and DHCP on Synology NAS. It is a little tricky the first time you do this especially if you have not come across bind or bind9 before. It seems a little over the top or just plain weird. You will only really need this if you have some local servers, computers or other devices that need to be accessed.
Updated for DSM 6.0, because Synology buggered about with stuff!
This may not work on earlier versions.
Updated for Ubuntu 14.04-3 LTS. If you are a home user and your network has grown such that you are tired of using all static IP addresses and having to configure the /etc/hosts files by hand, then use the great tool dnsmasq. See my How to set up dnsmasq. Dnsmasq is so much simpler to setup and maintain than bind9.
At some point you will need to refresh the lease on a network card, NIC, by sending a refresh command to your DHCP server.
To send the release to the DHCP client use the following. remember this will remember this will effectively turn off your network connection. If you are connected remotely you may loose your connection.
This post will explain how to Setup dnsmasq as DNS DHCP.
What is Dnsmaq
This description of dnsmasq shamelessly taken from the dnsmasq home page.
dnsmasq is a lightweight DNS, TFTP, PXE, router advertisement and DHCP server. It is intended to provide coupled DNS and DHCP service to a LAN.