google-cloud-dns Secondary DNS support

Question

I am trying to determine if Google Cloud DNS has support for secondary DNS (AXFR/IXFR) transfer via NOTIFY request? I can not find anything online and Google does not explicitly state it is not supported.

Answer 1

Google Cloud DNS currently does not support running as a secondary DNS server (with TSIG signed AXFR/IXFR on receipt of NOTIFY messages).

Nor does it support incoming AXFR/IXFR requests or send NOTIFY messages, in case that's what you meant.

If you are interested in secondary DNS because you want to spread your DNS authorities across multiple providers, you could try the alternative "multiple master" or "split authority" configuration, where you have two (or more) independent DNS services that are kept in synchronization from another source.

There are several DNS-specific tools to synchronize multiple DNS services, from Netflix’s Denominator, StackExchange’s DNSControl, and GitHub’s OctoDNS to Men & Mice’s commercial xDNS. You can also use HashiCorp’s Terraform to manage multiple DNS providers as well as many other cloud resources.

All of these support many different DNS providers and DNS name server software such as BIND. The support for specific record types and features varies by provider (and tool). DNSControl has a useful feature matrix showing support for specific features.

The following list of DNS providers and software shows the support by different tools as of November 2017,

• AWS Route 53: Denominator, DNSControl, OctoDNS, Terraform
• Azure: OctoDNS, Terraform
• BIND: DNSControl, Terraform(RFC2136)
• CloudFlare: DNSControl, OctoDNS, Terraform
• Digitalocean: DNSControl, Terraform
• DNSimple: DNSControl, OctoDNS, Terraform
• DnsMadeEasy: Terraform
• Dyn: Denominator, OctoDNS, Terraform
• Gandi: DNSControl
• Google Cloud DNS: DNSControl, OctoDNS, Terraform
• Knot: Terraform(RFC2136)
• Microsoft Active Directory: DNSControl, OctoDNS
• Namecheap: DNSControl
• Name.com: DNSControl
• NS1: DNSControl, OctoDNS, Terraform
• OpenStack Designate: Denominator
• OVH: OctoDNS
• PowerDNS: OctoDNS, Terraform
• Rackspace Cloud DNS: Denominator
• SoftLayer: DNSControl
• UltraDNS: Denominator, Terraform
• Vultr: DNSControl

Terraform can use RFC 2136 DNS Update to make changes to existing zones, but not to provision entirely new ones.

If you need support for another DNS provider, there are GitHub repositories for all the open source tools. Denominator is written in Java, OctoDNS is written in Python, and DNSControl and Terraform are written in Go.