CNAME chasing
CNAME chasing refers to a subsequent lookup of a DNS name returned from a CNAME
record answer to an initial query. Public DNS resolvers perform subsequent
lookup of CNAME answers according to their configuration. Generally, public
resolvers chase CNAME answers in any public zones.
When Trusted Cloud VMs use their metadata server (169.254.169.254) as
their name server, and no alternative name server is defined in an outbound
server policy of the VPC network, Cloud DNS performs
CNAME chasing as described in the following table.
| Source of CNAME answer |
Cloud DNS resolver behavior |
Cloud DNS private zone
with local records (not a forwarding zone)
|
Cloud DNS systems perform queries for the CNAME answer in
Cloud DNS private zones that are authorized for the
VPC network.
Cloud DNS systems don't perform queries for
the CNAME answer in any public DNS zones, including Cloud DNS
public zones.
|
| Cloud DNS forwarding zone
|
Cloud DNS systems don't perform queries for
any CNAME answers received from forwarding target name servers.
|
| Cloud DNS response policy zone
|
Cloud DNS systems don't perform queries for
any CNAME answers received from local data rules of response policy
zones.
|
What's next
- To find solutions for common issues that you might encounter when using
Cloud DNS, see Troubleshooting.
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Last updated 2025-08-07 UTC.
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