Resolver Functions and The Default Resolver

dns.resolver.resolve(qname: Name | str, rdtype: RdataType | str = RdataType.A, rdclass: RdataClass | str = RdataClass.IN, tcp: bool = False, source: str | None = None, raise_on_no_answer: bool = True, source_port: int = 0, lifetime: float | None = None, search: bool | None = None) → Answer

Query nameservers to find the answer to the question.

This is a convenience function that uses the default resolver object to make the query.

See dns.resolver.Resolver.resolve for more information on the parameters.

dns.resolver.resolve_address(ipaddr: str, *args: Any, **kwargs: Any) → Answer

Use a resolver to run a reverse query for PTR records.

See dns.resolver.Resolver.resolve_address for more information on the parameters.

dns.resolver.resolve_name(name: Name | str, family: int = AddressFamily.AF_UNSPEC, **kwargs: Any) → HostAnswers

Use a resolver to query for address records.

See dns.resolver.Resolver.resolve_name for more information on the parameters.

dns.resolver.canonical_name(name: Name | str) → Name

Determine the canonical name of name.

See dns.resolver.Resolver.canonical_name for more information on the parameters and possible exceptions.

dns.resolver.try_ddr(lifetime: float = 5.0) → None

Try to update the default resolver’s nameservers using Discovery of Designated Resolvers (DDR). If successful, the resolver will subsequently use DNS-over-HTTPS or DNS-over-TLS for future queries.

See dns.resolver.Resolver.try_ddr() for more information.

dns.resolver.zone_for_name(name: Name | str, rdclass: RdataClass = RdataClass.IN, tcp: bool = False, resolver: Resolver | None = None, lifetime: float | None = None) → Name

Find the name of the zone which contains the specified name.

Parameters:

• name (dns.name.Name or str) – An absolute query name.

• rdclass (dns.rdataclass.RdataClass) – The query class.

• tcp (bool) – If True, use TCP to make the query.

• resolver (dns.resolver.Resolver or None) – The resolver to use. If None, the default resolver is used.

• lifetime (float or None) – Total time to allow for the queries. If None, only the individual query limits of the resolver apply.

Raises:

• dns.resolver.NoRootSOA – If there is no SOA RR at the DNS root.

• dns.resolver.LifetimeTimeout – If the answer could not be found within the allotted lifetime.

Return type:

dns.name.Name

dns.resolver.query(qname: Name | str, rdtype: RdataType | str = RdataType.A, rdclass: RdataClass | str = RdataClass.IN, tcp: bool = False, source: str | None = None, raise_on_no_answer: bool = True, source_port: int = 0, lifetime: float | None = None) → Answer

Query nameservers to find the answer to the question.

This method calls resolve() with search=True, and is provided for backwards compatibility with prior versions of dnspython. See the documentation for the dns.resolver.resolve() method for further details.

dns.resolver.make_resolver_at(where: Name | str, port: int = 53, family: int = AddressFamily.AF_UNSPEC, resolver: Resolver | None = None) → Resolver

Make a stub resolver using the specified destination as the full resolver.

Parameters:

• where (dns.name.Name or str) – The domain name or IP address of the full resolver.

• port (int) – The port to use. Default is 53.

• family (int) – The address family. Used only when where is not an address literal. socket.AF_UNSPEC (default) uses the first address returned; otherwise the first address of the given family.

• resolver (dns.resolver.Resolver or None) – The resolver to use for hostname resolution. If None, the default resolver is used.

Return type:

dns.resolver.Resolver

dns.resolver.resolve_at(where: Name | str, qname: Name | str, rdtype: RdataType | str = RdataType.A, rdclass: RdataClass | str = RdataClass.IN, tcp: bool = False, source: str | None = None, raise_on_no_answer: bool = True, source_port: int = 0, lifetime: float | None = None, search: bool | None = None, port: int = 53, family: int = AddressFamily.AF_UNSPEC, resolver: Resolver | None = None) → Answer

Query nameservers to find the answer to the question.

This is a convenience function that calls dns.resolver.make_resolver_at() to make a resolver, and then uses it to resolve the query.

See dns.resolver.Resolver.resolve for more information on the resolution parameters, and dns.resolver.make_resolver_at for information about the resolver parameters where, port, family, and resolver.

If making more than one query, it is more efficient to call dns.resolver.make_resolver_at() and then use that resolver for the queries instead of calling resolve_at() multiple times.

dns.resolver.default_resolver: Resolver | None = None

The default resolver.

dns.resolver.get_default_resolver() → Resolver

Get the default resolver, initializing it if necessary.

dns.resolver.reset_default_resolver() → None

Re-initialize default resolver.

Note that the resolver configuration (i.e. /etc/resolv.conf on UNIX systems) will be re-read immediately.