Over the years, PowerDNS users have frequently asked us about our preferred DNS load balancing solution, and we’ve never had a satisfying answer for that. Users of dedicated hardware often tell us that vendors spend most of their time and effort on balancing HTTP, and frequently deliver substandard or even buggy DNS functionality.
In terms of software, one big PowerDNS deployment is happy with OpenBSD relayd, and it indeed does look powerful. Other operators have deployed keepalived, which is very strong from a networking standpoint, but does not offer a lot of DNS specifics.
But all in all, we never found any load balancing solution for DNS that made people truly happy.
more here..........http://blog.powerdns.com/2015/03/11/introducing-dnsdist-dns-abuse-and-dos-aware-query-distribution-for-optimal-performance/
In terms of software, one big PowerDNS deployment is happy with OpenBSD relayd, and it indeed does look powerful. Other operators have deployed keepalived, which is very strong from a networking standpoint, but does not offer a lot of DNS specifics.
But all in all, we never found any load balancing solution for DNS that made people truly happy.
more here..........http://blog.powerdns.com/2015/03/11/introducing-dnsdist-dns-abuse-and-dos-aware-query-distribution-for-optimal-performance/