Є сервер FreeBSD, з використанням dhclient для мережевого інтерфейсу.
Задача, оновити запис в власному сервері DNS з отриманим IP від DHCP сервером.
Встановлюю додатковий компонент pkg install samba-nsupdate.
 |
| nsupdate |
dhclient
Створюю скрипт dhclient-exit-hooks для dhclient.
/etc/dhclient-exit-hooks#!/bin/sh
/usr/bin/logger -t dhclient-exit-hooks REASON ${reason} IP: ${new_ip_address}
case "${reason}" in BOUND|RENEW|REBIND|REBOOT)
echo ${new_ip_address} ${reason}
/usr/local/etc/ddns/ddns.sh ${new_ip_address} ${reason}
;;
esac
Створюю теку /usr/local/etc/ddns, там завантажую файл ключа ddns.key для оновлення DNS з RFC 2136 і також цей скрипт:
nsupdate
/usr/local/etc/ddns/ddns.sh
#!/usr/bin/env /bin/sh
IP=$1
KEY=/usr/local/etc/ddns/ddns.key
NSUPDATE=/usr/local/bin/samba-nsupdate
DNSSERVER=your_dns_server
DNSHOST=host.example.net
if [ ! -z ${IP} ];then
echo updating: ${IP} [ $2 ] - ${USER}
/usr/bin/logger -t dyndns updating: ${IP} [ $2 ] - ${USER}
if [ -f ${KEY} ];then
${NSUPDATE} -4 -k ${KEY} <<EOF
server ${DNSSERVER} 53
update delete ${DNSHOST}
update add ${DNSHOST} 300 A ${IP}
send
EOF
else
logger -t dyndns no key file ${KEY}
fi
else
echo IP missed
logger -t dyndns IP missed
fi
BIND
ddns-confgen -a hmac-sha512 -z host.example.net
# To activate this key, place the following in named.conf, and
# in a separate keyfile on the system or systems from which nsupdate
# will be run:
key "ddns-key.host.example.net" {
algorithm hmac-sha512;
secret "SdimvwKG5SDqeS7hD+C6ap89sRN4I2EuYrJKHFXtJ83CuUF6kbELxrv5OgVeVctzyqbafcQTGJgQh/svkv+/Yg==";
};
# Then, in the "zone" definition statement for "host.example.net",
# place an "update-policy" statement like this one, adjusted as
# needed for your preferred permissions:
update-policy {
grant ddns-key.host.example.net zonesub ANY;
};
# After the keyfile has been placed, the following command will
# execute nsupdate using this key:
nsupdate -k
