DNS "cluster"

DNS is HA by default...

Setup of PowerDNS (as slave)

Installation

sudo apt-get install pdns-backend-sqlite3

Populating the database schema

sqlite3 /var/spool/powerdns/powerdns.sqlite3 < /usr/share/doc/pdns-backend-sqlite3/schema.sqlite3.sql

Configuration

/etc/powerdns/pdns.conf

version-string=PowerDNS
launch=gsqlite3
gsqlite3-database=/var/spool/powerdns/powerdns.sqlite3
daemon=yes
slave=yes
guardian

Add the slave zone

# sqlite3 /var/spool/powerdns/powerdns.sqlite3
Enter ".help" for usage hints.
sqlite> INSERT INTO domains (name,type,master) VALUES ('example.net', 'SLAVE', '198.51.100.101');

... and fire up PowerDNS. Watch /var/log/syslog for issue.