Networking::DNSResolver

Introduced : BIG-IP_v12.0.0
The DNSResolver interface allows you to manage DNS resolvers. The DNS resolver resolves DNS queries and caches the results. It does not validate DNSSEC responses. A forward zone can be defined for a DNS resolver. If the answer to a query is not available in the cache, a DNS resolver configured with a forward zone will forward the query to the nameserver specified for the zone if the name in the query matches the configured zone name.

Methods

Method Description Introduced
add_forward_zone Adds the specified forward zones to the specified DNS resolvers. BIG-IP_v12.0.0
add_nameserver Adds the specified nameservers to a set of forward zones for the specified DNS resolvers. BIG-IP_v12.0.0
create Creates a set of DNS resolvers. BIG-IP_v12.0.0
delete_all_dns_resolvers Deletes all DNS resolvers. BIG-IP_v12.0.0
delete_dns_resolver Deletes a set of DNS resolvers. BIG-IP_v12.0.0
get_answer_default_zones_state Gets whether the system answers DNS queries for the default zones (localhost, reverse 127.0.0.1 and ::1, and AS112) for a set of DNS resolvers. BIG-IP_v12.0.0
get_cache_size Gets the sizes of the internal DNS resolver cache for a set of DNS resolvers. BIG-IP_v12.0.0
get_forward_zone Gets the names of forward zones for the specified DNS resolvers. A given zone name should only use the symbols allowed for a fully qualified domain name (FQDN), namely ASCII letters &aposa&apos though &aposz&apos, digits &apos0&apos through &apos9&apos, hyphen &apos-&apos, and period &apos.&apos. For example &apossite.example.com&apos would be a valid zone name. A DNS resolver configured with a forward zone will forward any queries that resulted in a cache-miss (because the answer was not available in the cache) and which also match a configured zone name, to the nameserver specified on the zone. If no nameservers are specified on the zone, an automatic SERVFAIL is returned. When a forward zone&aposs nameserver returns a valid response to the DNS resolver, that response is cached and then returned to the requestor. BIG-IP_v12.0.0
get_list Gets a list of names for all DNS resolvers. BIG-IP_v12.0.0
get_nameserver Gets the nameservers for the specified forward zones for the specified DNS resolvers. If more than one nameserver is configured for a given forward zone, a matching query will be sent to the nameserver that is currently deemed the most responsive, based on RTTs. Configuring multiple nameservers allows the system to automatically recover when there is a non-responsive server. BIG-IP_v12.0.0
get_randomize_query_character_case_state Gets whether to randomly vary the case of letters in domain names queried for a set of DNS resolvers. BIG-IP_v12.0.0
get_route_domain Gets the route domains for a set of DNS resolvers. BIG-IP_v12.0.0
get_use_ipv4_state Gets whether IPv4 can be used for issuing queries for a set of DNS resolvers. BIG-IP_v12.0.0
get_use_ipv6_state Gets whether IPv6 can be used for issuing queries for a set of DNS resolvers. BIG-IP_v12.0.0
get_use_tcp_state Gets whether TCP can be used for issuing queries for a set of DNS resolvers. BIG-IP_v12.0.0
get_use_udp_state Gets whether UDP can be used for issuing queries for a set of DNS resolvers. BIG-IP_v12.0.0
get_version Get the version information for this interface. BIG-IP_v12.0.0
remove_all_forward_zones Removes all forward zones from the specified DNS resolvers. BIG-IP_v12.0.0
remove_all_nameservers Removes all nameservers from the specified forward zones for the specified DNS resolvers. BIG-IP_v12.0.0
remove_forward_zone Removes the specified forward zones from the specified DNS resolvers. BIG-IP_v12.0.0
remove_nameserver Removes the specified nameservers from the specified forward zones for the specified DNS resolvers. BIG-IP_v12.0.0
set_answer_default_zones_state Sets whether the resolver answers DNS queries for the default zones (localhost, reverse 127.0.0.1 and ::1, and AS112) for a set of DNS resolvers. The default value is disabled, meaning that the system passes along the DNS queries for the default zone. BIG-IP_v12.0.0
set_cache_size Sets the sizes of the internal DNS resolver cache for a set of DNS resolvers. After the cache reaches this size, when new or refreshed content arrives, the system removes expired and older content and caches the new or updated content. The default is 5767168 bytes. BIG-IP_v12.0.0
set_randomize_query_character_case_state Sets whether to randomly vary the case of letters in domain names queried for a set of DNS resolvers. If disabled, the resolver will not vary the case of letters in domain names queried. The DNS standards require that nameservers treat query names case-insensitively. Domain names with the same letters, regardless of the case, should resolve to the same IP address. On the other hand, for the response, nameservers should preserve the original case that appeared in the request. This technique will help to reduce the risk of cache poisioning. The default value is enabled. BIG-IP_v12.0.0
set_route_domain Sets the route domains for a set of DNS resolvers. A resolver will use the specified route domain for any outbound DNS traffic. The default value is the default route domain specified in the network route domain configuration. BIG-IP_v12.0.0
set_use_ipv4_state Sets whether IPv4 can be used for issuing queries for a set of DNS resolvers. If disabled, the resolver will not attempt to resolve queries using IPv4. IPv4 and IPv6 cannot be disabled simultaneously. There may be a case where one is enabled and the other disabled and you want to swap their states. To toggle these, both must be enabled first, or a transaction must be used. The default value is enabled. BIG-IP_v12.0.0
set_use_ipv6_state Sets whether IPv6 can be used for issuing queries for a set of DNS resolvers. If disabled, the resolver will not attempt to resolve queries using IPv6. IPv4 and IPv6 cannot be disabled simultaneously. There may be a case where one is enabled and the other disabled and you want to swap their states. To toggle these, both must be enabled first, or a transaction must be used. The default value is enabled. BIG-IP_v12.0.0
set_use_tcp_state Sets whether TCP can be used for issuing queries for a set of DNS resolvers. If disabled, the resolver will not attempt to resolve queries over TCP. UDP and TCP cannot be disabled simultaneously. There may be a case where one is enabled and the other disabled and you want to swap their states. To toggle these, both must be enabled first, or a transaction must be used. The default value is enabled. BIG-IP_v12.0.0
set_use_udp_state Sets whether UDP can be used for issuing queries for a set of DNS resolvers. If disabled, the resolver will not attempt to resolve queries over UDP. UDP and TCP cannot be disabled simultaneously. There may be a case where one is enabled and the other disabled and you want to swap their states. To toggle these, both must be enabled first, or a transaction must be used. The default value is enabled. BIG-IP_v12.0.0

Structures

Structure Description

Enumerations

Enumeration Description

Exceptions

Exception Description

Constants

Constant Type Value Description

Aliases

Alias Type Description

See Also

Warning

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Sample Code


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