Redondant DNS

[Me.B]

If you want a redundant DNS try PowerDNS in Slave mode (you need a separate VPS for this)
It will do auto sync with your DNS and has his own MySQL backend, need some tricks but it worked for me
Some links:
http://vpstutorial.com/setup-powerdns-centos-6/
https://www.digitalocean.com/community/t...os-6-3-x64

With some work you can do the same with bind and setup a slave bind server on a second VPS too...