LocalLB::DNSCache

Introduced : BIG-IP_v11.2.0
The DNSCache interface allows you to manage DNS caches. There are three types of DNS caches depending on whether DNS resolving and DNSSEC validation are needed: Transparent - cache with no resolving nor DNSSEC validation. Resolver - cache which resolves DNS but does not validate DNSSEC. Validating Resolver - cache which resolves DNS and validates DNSSEC. Each cache has multiple internal caches described below. For answering DNS queries, the message cache will be checked first followed by the resource record cache: Message Cache - cache of entire DNS messages. Resource Record Cache - cache of individual resource records. Name Server Cache - cache of name servers obtained from DNS resolving. DNSSEC Key Cache - cache of keys obtained from validating DNSSEC.

Methods

Method Description Introduced
add_dlv_anchor Adds DNSSEC Lookaside Validation (DLV) anchors for a set of DNS caches. BIG-IP_v11.2.0
add_forward_zone Adds the specified forward zones for a set of DNS caches. BIG-IP_v11.5.0
add_nameserver Adds the specified nameservers for a set of forward zones on a set of DNS caches. BIG-IP_v11.5.0
add_response_policy_zone Adds the specified response policy zone for a set of DNS caches. A DNS Cache configured with a response policy zone checks the query name in a DNS request as well as information in the response against the data in the configured zones. If a match is found, the DNS response is modified according to the configured action. For example, if the action is NXDOMAIN, the request is modified to give an NXDOMAIN result. BIG-IP_v11.6.0
add_root_hint Adds root hints for a set of DNS caches. BIG-IP_v11.2.0
add_trust_anchor Adds to the DNSSEC validator trust anchors for a set of DNS caches. BIG-IP_v11.2.0
create Creates the specified DNS caches. BIG-IP_v11.2.0
delete_all_dns_caches Deletes all DNS caches. BIG-IP_v11.2.0
delete_all_key_records Deletes all DNSSEC key records for a set of DNS caches. BIG-IP_v11.2.0
delete_all_message_records Deletes all DNS message records for a set of DNS caches. BIG-IP_v11.2.0
delete_all_nameserver_records Deletes all nameserver records for a set of DNS caches. BIG-IP_v11.2.0
delete_all_resource_records Deletes all resource records for a set of DNS caches. BIG-IP_v11.2.0
delete_dns_cache Deletes the specified DNS caches. BIG-IP_v11.2.0
get_allowed_query_time Gets the allowed query time for a set of DNS caches. BIG-IP_v11.3.0
get_answer_default_zones_state Gets whether a set of DNS caches answer default zones. BIG-IP_v11.2.0
get_description Gets the descriptions for a set of DNS caches. BIG-IP_v11.2.0
get_dlv_anchor Gets the DNSSEC Lookaside Validation (DLV) anchors for a set of DNS caches. These are in the form of dig output. For example, run the command: dig BIG-IP_v11.2.0
get_forward_zone Gets the names of forward zones for a set of DNS caches. 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 Cache 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 Cache, that response is cached and then returned to the requestor. BIG-IP_v11.5.0
get_ignore_cd_state Gets whether to ignore the checking disabled bit for a set of DNS caches. BIG-IP_v11.2.0
get_key_cache_size Gets the size in bytes of the DNSSEC key cache for a set of DNS caches. BIG-IP_v11.2.0
get_list Gets a list of DNS cache names. BIG-IP_v11.2.0
get_local_zone Gets the local zone data for a set of DNS caches. BIG-IP_v11.4.0
get_maximum_concurrent_queries Gets the maximum concurrent distinct queries for a set of DNS caches. BIG-IP_v11.3.0
get_maximum_tcp_flows Gets the maximum concurrent TCP flows for a set of DNS caches. BIG-IP_v11.2.0
get_maximum_udp_flows Gets the maximum concurrent TCP flows for a set of DNS caches. BIG-IP_v11.2.0
get_message_cache_size Gets the size in bytes of the message cache for a set of DNS caches. BIG-IP_v11.2.0
get_nameserver Gets the nameservers for the specified forward zones on a set of DNS caches. If more than one nameserver is listed for a given forward zone, a matching query will be sent to the nameserver that is currently deemed the most responsive, based on RTTs. If no response is received within a certain window of time, the DNS Cache will resend the query to another nameserver with an increased wait window, until a response is received. BIG-IP_v11.5.0
get_nameserver_cache_count Gets the maximum number of name server cache entries for a set of DNS caches. BIG-IP_v11.2.0
get_prefetch_key_state Gets whether a set of validating-resolver DNS caches will prefetch DNSSEC keys. BIG-IP_v11.2.0
get_randomize_query_name_case_state Gets whether to randomly vary the case of letters in domain names for a set of DNS caches. BIG-IP_v11.3.0
get_resource_record_cache_size Gets the size in bytes of the resource record cache for a set of DNS caches. BIG-IP_v11.2.0
get_response_policy_zone Gets the response policy zones for a set of DNS caches. BIG-IP_v11.6.0
get_response_policy_zone_action Gets the response policy zone actions for a set of DNS caches and zones. BIG-IP_v11.6.0
get_response_policy_zone_walled_garden Gets the response policy zone walled garden for a set of DNS caches and zones. BIG-IP_v11.6.0
get_root_hint Gets the root hints for a set of DNS caches. BIG-IP_v11.2.0
get_route_domain Gets the route domain for a set of DNS caches. BIG-IP_v11.2.0
get_rrset_rotate_type Gets the method of resource record rotation used within cached responses. BIG-IP_v12.1.0
get_statistics Gets the statistics for a set of DNS caches. BIG-IP_v11.2.0
get_trust_anchor Gets the DNSSEC validator trust anchors for a set of DNS caches. These are in the form of dig output. For example, run the command: dig BIG-IP_v11.2.0
get_type Gets the cache types for a set of DNS caches. BIG-IP_v11.2.0
get_unwanted_reply_threshold Gets the size of the unwanted reply threshold for a set of DNS caches. BIG-IP_v11.2.0
get_use_ipv4_state Gets whether to use IPv4 for a set of DNS caches. BIG-IP_v11.2.0
get_use_ipv6_state Gets whether to use IPv6 for a set of DNS caches. BIG-IP_v11.2.0
get_use_tcp_state Gets whether to use TCP for a set of DNS caches. BIG-IP_v11.2.0
get_use_udp_state Gets whether to use UDP for a set of DNS caches. BIG-IP_v11.2.0
get_version Get the version information for this interface. BIG-IP_v11.2.0
remove_all_dlv_anchors Removes all DNSSEC Lookaside Validation (DLV) anchors for a set of DNS caches. BIG-IP_v11.2.0
remove_all_forward_zones Removes all forward zones for a set of DNS caches. BIG-IP_v11.5.0
remove_all_local_zones Removes all local zone data for a set of DNS caches. BIG-IP_v11.4.0
remove_all_nameservers Removes all nameservers for the specified forward zones on a set of DNS caches. BIG-IP_v11.5.0
remove_all_response_policy_zones Removes all response policy zones for a set of DNS caches. BIG-IP_v11.6.0
remove_all_root_hints Removes all root hints for a set of DNS caches. BIG-IP_v11.2.0
remove_all_trust_anchors Removes all DNSSEC validator trust anchors for a set of DNS caches. BIG-IP_v11.2.0
remove_dlv_anchor Removes DNSSEC Lookaside Validation (DLV) anchors for a set of DNS caches. BIG-IP_v11.2.0
remove_forward_zone Removes the specified forward zones for a set of DNS caches. BIG-IP_v11.5.0
remove_nameserver Removes the specified nameservers for a set of forward zones on a set of DNS caches. BIG-IP_v11.5.0
remove_response_policy_zone Removes the specified response policy zone for a set of DNS caches. BIG-IP_v11.6.0
remove_root_hint Removes the specified root hints for a set of DNS caches. BIG-IP_v11.2.0
remove_trust_anchor Removes DNSSEC validator trust anchors for a set of DNS caches. BIG-IP_v11.2.0
replace_local_zone Replaces the local zone for a set of DNS caches. BIG-IP_v11.4.0
reset_statistics Resets the statistics for a set of DNS caches. BIG-IP_v11.2.0
set_allowed_query_time Sets the allowed query time for a set of DNS caches. This is used set the time allowed for a query to stay in the queue before replaced by a new query when the number of concurrrent distinct queries exceeds the limit. BIG-IP_v11.3.0
set_answer_default_zones_state Sets whether a set of DNS caches answer default zones. BIG-IP_v11.2.0
set_description Sets the description for a set of DNS caches. This is an arbitrary field which can be used for any purpose. BIG-IP_v11.2.0
set_ignore_cd_state Sets whether to ignore the checking disabled (CD) bit for a set of DNS caches. BIG-IP_v11.2.0
set_key_cache_size Sets the size in bytes of the DNSSEC key cache for a set of DNS caches. The cache will be initiated and maintained with this amount of memory regardless of the number of entries. If more space is needed, the cache will evict older but valid entries. BIG-IP_v11.2.0
set_maximum_concurrent_queries Sets the maximum concurrent distinct queries for a set of DNS caches. This is used to limit the number of concurrent distinct queries that a resolver allows. A query is identified by query name, type, and class. BIG-IP_v11.3.0
set_maximum_tcp_flows Sets the maximum concurrent TCP flows for a set of DNS caches. This is used to limit the number of simultaneous outbound TCP connections that a resolver can use to query DNS servers. BIG-IP_v11.2.0
set_maximum_udp_flows Sets the maximum concurrent UDP flows for a set of DNS caches. This is used to limit the number of simultaneous outbound UDP connections that a resolver can use to query DNS servers. BIG-IP_v11.2.0
set_message_cache_size Sets the size in bytes of the message cache for a set of DNS caches. The cache will be initiated and maintained with this amount of memory regardless of the number of entries. If more space is needed, the cache will evict older but valid entries. BIG-IP_v11.2.0
set_nameserver_cache_count Sets the maximum number of name server cache entries for a set of DNS caches. BIG-IP_v11.2.0
set_prefetch_key_state Sets whether a set of validating-resolver DNS caches will prefetch DNSSEC keys. BIG-IP_v11.2.0
set_randomize_query_name_case_state Sets whether to randomly vary the case of letters in domain names queried for a set of DNS caches. 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 letter, 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. BIG-IP_v11.3.0
set_resource_record_cache_size Sets the size in bytes of the resource record cache for a set of DNS caches. The cache will be initiated and maintained with this amount of memory regardless of the number of entries. If more space is needed, the cache will evict older but valid entries. BIG-IP_v11.2.0
set_route_domain Sets the route domain for a set of DNS caches. A resolver will use the specified route domain for any outbound DNS traffic. BIG-IP_v11.2.0
set_rrset_rotate_type Sets the method of resource record rotation used within cached responses. The method chosen will dictate which record of each resource record set to return first, and return answers in circular linked list order from there. The default is “none”. BIG-IP_v12.1.0
set_unwanted_reply_threshold Sets the size of the unwanted reply threshold for a set of DNS caches. The threshold is the number of replies received to DNS queries which were not initiated by the cache and may indicate a DNS attack. If the threshold is hit, an SNMP trap and log message are generated. The default is 0. BIG-IP_v11.2.0
set_use_ipv4_state Sets whether to use IPv4 for a set of DNS caches. 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. BIG-IP_v11.2.0
set_use_ipv6_state Sets whether to use IPv6 for a set of DNS caches. 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. BIG-IP_v11.2.0
set_use_tcp_state Sets whether to use TCP for a set of DNS caches. 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. BIG-IP_v11.2.0
set_use_udp_state Sets whether to use UDP for a set of DNS caches. 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. BIG-IP_v11.2.0

Structures

Structure

Description

DNSCacheStatisticEntry

A struct that describes statistics for a particular DNS cache.

DNSCacheStatistics

A struct that describes DNS cache statistics and timestamp.

LocalZone

A struct that describes DNS cache local zone.


Enumerations

Enumeration Description

Exceptions

Exception Description

Constants

Constant Type Value Description

Aliases

Alias Type Description
DNSCacheStatisticEntrySequence DNSCacheStatisticEntry [] A sequence of DNS cache statistics.
LocalZoneSequence LocalZone [] A sequence of DNS cache local zones.
LocalZoneSequenceSequence LocalZone [] [] A sequence of DNS cache local zone sequences.

See Also

Warning

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Sample Code


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