- Dynamic DNS
- Of Masters and Slaves
- Accepting and Doing Updates
- TSIG
- The Dynamic Zone
- The Client
- Update Prerequisites
- Update Actions
- Using nsupdate
- Slave Server Issues
- Reverse Zones
- A One Host Zone
- DHCP
- Mixing DNS and DHCP Implementations
- DHCP and Static DNS Entries
- DHCP and Dynamic DNS Entries
- Dynamic Updates by the Client
DHCP and Static DNS Entries
Due to the lack of support for dynamic DNS support in DHCP 2 and, more significantly perhaps, the potential management overhead if everyone could grab any name and get an IP address to go, a lot of sites use fixed names for their DHCP range. In BIND 8 it's quite easy to enter such ranges in zone files too, using $GENERATE which was introduced in Chapter 2. In such a case, the 16 new penguin employee computers would be assigned an IP range, such as 192.168.55.220 to 229, and the names would be entered thus:
$GENERATE 220-229 dhcp$ A 192.168.55.$
The names would be dhcp220.penguin.bv and so forth. This is a good way to do it; it is simple and low maintenance. For hosts that you want to have fixed IP numbers or fixed hostname, ISC DHCP 2 provides a way for you to assign them. In the dhcpd.conf file, insert something like this:
host gentoo { hardware ethernet 00:60:1d:1f:1e:f7; fixed-address 192.168.55.55; }
This assigns the given IP address to the host bearing the given Ethernet address. Just enter the name in DNS in the usual manner. The "gentoo" part of the host statement is arbitrary, but it would be good policy to assign 192.168.55.55 the name gentoo.penguin.bv.