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
A struct that describes statistics for a particular DNS cache.
A struct that describes DNS cache statistics and timestamp.
A struct that describes DNS cache local zone.
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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