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DNS

This reference covers all of Pomerium's DNS Settings:

Failure Refresh Rate​

Failure Refresh Rate sets the DNS refresh rate when requests are failing.

How to Configure​

Config file keysEnvironment variablesTypeDefault
dns_failure_refresh_rateDNS_FAILURE_REFRESH_RATEstring (Go Duration formatting)5s

Examples​

dns_failure_refresh_rate: 10s

Lookup Family​

Lookup Family sets the DNS IP address resolution policy.

How to Configure​

Config file keysEnvironment variablesTypeDefault
dns_lookup_familyDNS_LOOKUP_FAMILYstringV4_PREFERRED

Examples​

default_lookup_family: AUTO
DEFAULT_LOOKUP_FAMILY=V6_ONLY

Options​

OptionsDescription
DEFAULT (Enterprise only)Defers to configuration settings or default if none specified
AUTODNS resolver will first perform a lookup for addresses in the IPv6 family and fallback to a lookup for addresses in the IPv4 family
V4_ONLYDNS resolver will only perform a lookup for addresses in the IPv4 family
V6_ONLYDNS resolver will only perform a lookup for addresses in the IPv6 family
V4_PREFERREDDNS resolver will first perform a lookup for addresses in the IPv4 family and fallback to a lookup for addresses in the IPv6 family
ALLDNS resolver will perform a lookup for both IPv4 and IPv6 families, and return all resolved addresses

See the Envoy docs for more information about these options.

Query Timeout​

Query Timeout sets the timeout for DNS queries.

How to Configure​

Config file keysEnvironment variablesTypeDefault
dns_query_timeoutDNS_QUERY_TIMEOUTstring (Go Duration formatting)5s

Examples​

dns_query_timeout: 10s

Query Tries​

Query Tries sets the number of times a DNS query will be re-tried.

How to Configure​

Config file keysEnvironment variablesTypeDefault
dns_query_triesDNS_QUERY_TRIESinteger4

Examples​

dns_query_tries: 7

Refresh Rate​

Refresh Rate sets the DNS refresh rate.

How to Configure​

Config file keysEnvironment variablesTypeDefault
dns_refresh_rateDNS_REFRESH_RATEstring (Go Duration formatting)DNS record TTL, or 5s if not set

Examples​

dns_refresh_rate: 10s

Resolvers​

Resolvers allows you to specify a list of custom DNS resolvers for Pomerium to use instead of the system default. Each resolver should be specified as a URL in the format udp://<ip>:<port> or tcp://<ip>:<port>.

How to Configure​

Config file keysEnvironment variablesTypeDefault
dns_resolversDNS_RESOLVERSarray of stringsSystem DNS resolvers

Examples​

dns_resolvers:
- udp://1.1.1.1:53
- udp://8.8.8.8:53
dns_resolvers:
- tcp://1.1.1.1:53

UDP Max Queries​

UDP Max Queries sets the maximum number of queries before a new UDP port is opened.

How to Configure​

Config file keysEnvironment variablesTypeDefault
dns_udp_max_queriesDNS_UDP_MAX_QUERIESinteger100

Examples​

dns_udp_max_queries: 100

Use TCP​

Use TCP configures Pomerium to use TCP instead of UDP for DNS queries.

How to Configure​

Config file keysEnvironment variablesTypeDefault
dns_use_tcpDNS_USE_TCPbooleanfalse

Examples​

dns_use_tcp: true