Dynamic DNS and DHCP on CentOS 5.x (Stand alone)

Distro: CentOS 5.5 64bit
Domain: systeminteg.com
Hostname: pdc-srv.systeminteg.com
IP Address: 192.168.1.1/24

Installation packages:

yum install bind bind-chroot bind-libs bind-utils caching-nameserver dhcpd ntp –y

Generate a key for rndc.key

cd /var/named/chroot/etc
rndc-confgen > rndc.key
chown root:named rndc.key

Configuration:

1. DHCP:
   First backup the curent config file
   
   

   cp /etc/dhcpd.conf /etc/dhcpd.conf.ori

   Edit /etc/dhcpd.conf as:
   

   authoritative;
   option domain-name "systeminteg.com";
   option domain-name-servers 192.168.1.1;
   option netbios-name-servers 192.168.1.1;
   # Allow booting and booting from network
   allow booting;
   allow bootp;
   #Below is TFTP server and kernel for network booting Ex: File server etc…
   next-server 192.168.1.5;
   filename "pxelinux.0";
   ddns-update-style interim;
   ddns-updates on;
   ddns-domainname "systeminteg.com";
   include "/etc/dhcpd.global";

   
   Edit /etc/dhcpd.global as:

   include "/etc/rndc.key";
   zone systeminteg.com {
      primary 127.0.0.1;
      key rndckey;
   }
   zone 1.168.192.in-addr.arpa {
      primary 127.0.0.1;
      key rndckey;
   }
   subnet 192.168.1.0 netmask 255.255.255.0 {
      pool {
         deny dynamic bootp clients;
         option routers 192.168.1.254;
         range 192.168.1.25 192.168.1.50;
      }
     pool {
         option routers 192.168.1.254;
         range 192.168.1.51 192.168.1.55;
      }
      allow unknown-clients;
      ignore client-updates;
   }

   Example /etc/rndc.key file

   # Start of rndc.conf
   key "rndckey" {
      algorithm hmac-md5;
      secret "v03a9FPqIihkB/Hdg5ke1Q==";
   };
   #options {
   # default-key "rndckey";
   # default-server 127.0.0.1;
   # default-port 953;
   #};
   # End of rndc.conf

2. DNS:
   Edit /var/named/chroot/etc/named.conf

include "/etc/rndc.key";
controls {
   inet 127.0.0.1 allow { 127.0.0.1; } keys { "rndckey"; };
   inet 192.168.100.1 allow { 192.168.1.0/24; } keys { "rndckey"; };
};
options {
   directory "/var/named";
   pid-file "/var/run/named/named.pid";
   recursion yes;
   allow-recursion {
      127.0.0.1;
      192.168.1.0/24;
   };
   forwarders {
      208.67.222.222;
      208.67.220.220;
   };
   listen-on {
      127.0.0.1;
      192.168.1.1;
   };
   query-source address * port 53;
   version "REFUSED";
   allow-query {
      127.0.0.1;
      192.168.1.0/24;
   };
};
server 192.168.1.1 {
   keys { rndckey; };
};
zone "." IN {
   type hint;
   file "named.ca";
};
zone "systeminteg.com" IN {
   type master;
   file "data/systeminteg.com.zone";
   allow-update { key "rndckey"; };
   allow-query { any; };
};
zone "1.168.192.in-addr.arpa" IN {
   type master;
   file "data/1.168.192.zone";
   allow-update { key "rndckey"; };
   allow-query { any;} ;
};

chown root:named /var/named/chroot/etc/named.conf

Create zone files
Create /var/named/chroot/var/named/data/systeminteg.com.zone

$TTL 38400
@                    IN               SOA        pdc-srv.systeminteg.com. admin.systeminteg.com. (
                                                       20110201        ; serial
                                                       10800             ; refresh (3 hours)
                                                       3600               ; retry (1 hour)
                                                       604800           ; expire (1 week)
                                                       86400             ; minimum (1 day)
)
                        NS                           pdc-srv.systeminteg.com.
pdc-srv              A                            192.168.1.1
dns                   A                            192.168.1.1
ns                     A                            192.168.1.1

Create /var/named/chroot/var/named/data/1.168.192.zone

$TTL 38400
@                    IN               SOA        pdc-srv.systeminteg.com. admin.systeminteg.com. (
                                                       20110201        ; serial
                                                       10800             ; refresh (3 hours)
                                                       3600               ; retry (1 hour)
                                                       604800           ; expire (1 week)
                                                       86400             ; minimum (1 day)
)
                        NS                           pdc-srv.systeminteg.com.
1                      PTR                         pdc-srv.systeminteg.com.

chown named:named /var/named/chroot/var/named/data/*


3. NTP:
   Create /etc/cron.hourly/timesync.sh

   #!/bin/bash
   ntpdate –s 0.rhel.pool.ntp.org

   chmod +x /etc/cron.houtly/timesync.sh
   /etc/cron.hourly/timesync.sh