In this chapter, we introduced the Domain Name System (DNS), which is the internet's method of mapping hostnames to IP addresses; showed how it works, and briefly mentioned the security and privacy issues it raises. pfSense is capable of acting as a DNS server, and we discussed how to configure a DNS server, and how to minimize the risk of end users circumventing the network’s DNS policy. However, sometimes we need to have a form of DNS that updates faster than traditional DNS, and thus we showed you how to configure DDNS in pfSense. Finally, we introduced two services that pfSense is also capable of providing: NTP and SNMP.
In the next chapter, we will introduce something we briefly mentioned in this and previous chapters, but did not fully elaborate on: firewall rules and Network Address Translation (NAT).