> DNS Client Configuration Mode Commands
> The DNS Client Configuration Mode is used to manage the system’s DNS interface and caching parameters.
> Important: The commands or keywords/variables that are available are dependent on platform type, product version, and installed license(s).
> bind
> Binds the DNS client to a pre-configured logical IP interface.
> Product
> MME, SCM, SGSN
> Privilege
> Security Administrator, Administrator
> Syntax
> bind { address ip_address [ port number ] | query-over-gtp }
> no bind address
> no
> Removes the binding of the client to a specified interface.
> ip_address
> Specifies the IP address of the interface to which the DNS client is being bound. ip_address must be expressed in IPv4 dotted decimal notation.
> port number
> Default: 6011
> Specifies the UDP port number of the interface to which the DNS client is being bound. number must be an integer value from 1 to 65535.
> query-over-gtp
> Specifies that DNS client query is to be performed over GTP.
> Usage
> Use this command to associated the client with a specific logical IP address.
> Example
> The following command binds the DNS client to a logical interface with an IP address of 1.2.3.4 and a port number of 6000:
> bind address 1.2.3.4 port 6000
> cache algorithm
> Configures the method of use of the DNS VPN and session cache.
> Product
> MME, SCM, SGSN
> Privilege
> Security Administrator, Administrator
> Syntax
> cache algorithm { central | local } { FIFO | LRU | LFU }
> default cache algorithm { central | local }
> default
> Sets the DNS VPN and session cache method to default setting.
> central | local
> central: Specifies the central proclet (VPN manager)
> local: Specifies the local proclet (session manager)
> FIFO | LRU | LFU
> FIFO: First in first out. This is the default setting for the central proclet.
> LRU: Least recently used. This is the default value for the local proclet.
> LFU: Least frequently used.
> Usage
> Use this command to configure the method by which entries are added and removed from the DNS cache.
> Example
> The following command configures the cache algorithm for the central proclet to least frequently used (LFU):
> cache algorithm central lfu
> cache size
> Configures the maximum number of entries allowed in the DNS cache.
> Product
> MME, SCM, SGSN
> Privilege
> Security Administrator, Administrator
> Syntax
> cache size { central | local } max_size
> default cache size { central | local }
> default
> Sets the maximum number of entries allowed in the DNS cache to default setting.
> { central | local } max_size
> central max_size: Specifies the maximum number of entries allowed in the central proclet cache. max_size must be an integer value from 100 to 65535 in length. The default value for the central proclet is 50000.
> local max_size: Specifies the maximum number of entries allowed in the local proclet cache. max_size must be an integer value from 100 to 65535 in length. The default value for the local proclet is 1000.
> Usage
> Use this command to configure the maximum number of entries allowed in the DNS cache.
> Example
> The following command configures the cache size of the central proclet to 20000:
> cache size central 20000
> cache ttl
> Configures the DNS cache time to live (TTL) for positive and negative responses.
> Product
> MME, SCM, SGSN
> Privilege
> Security Administrator, Administrator
> Syntax
> cache ttl { negative | positive } seconds
> default cache ttl { negative | positive }
> no cache [ ttl { negative | positive } ]
> no
> Disables any or all configured DNS cache parameters.
> default
> Sets the DNS cache time to live for positive and negative responses to default setting.
> { negative | positive } seconds
> negative seconds: Specifies the time to live for negative responses. seconds must be an integer value from 60 to 86400. The default value is 60 seconds.
> positive seconds: Specifies the time to live for positive responses. seconds must be an integer value from 60 to 86400. The default value is 86400 seconds (1 day).
> Usage
> Use this command to adjust the DNS cache time to live.
> Example
> The following commands set the TTL DNS cache to 90 seconds for negative responses and 43200 seconds for positive responses:
> cache ttl negative 90
> cache ttl positive 43200
> case-sensitive
> Configures the case sensitivity requirement for responses to DNS requests.
> Product
> MME, SCM, SGSN
> Privilege
> Administrator
> Syntax
> [ default | no ] case-sensitive response
> default
> Returns the command to it’s default setting of disabled.
> no
> Disables the requirement for case sensitivity for DNS responses.
> Usage
> Use this command to require case sensitivity (identical case usage between request and response) on all responses to DNS request messages.
> end
> Exits the current mode and returns to the Exec Mode.
> Product
> All
> Privilege
> Security Administrator, Administrator
> Syntax
> end
> Usage
> Change the mode back to the Exec mode.
> exit
> Exits the current mode and returns to the previous mode.
> Product
> All
> Privilege
> Security Administrator, Administrator
> Syntax
> exit
> Usage
> Return to the previous mode.
> resolver
> Configure the number of DNS query retries and the retransmission interval once the response timer times out.
> Product
> MME, SGSN
> Privilege
> Security Administrator, Administrator
> Syntax
> resolver { number-of-retries retries | retransmission-interval time }
> default { number-of-retries | retransmission-interval }
> default
> Use this keyword to reset the specified resolver configuration to the default.
> number-of-retries retries
> Configures the number of DNS query retries on DNS response timeout.
> retries: enter an integer from 0 to 4. Default is 2 retries.
> retransmission-interval time
> Configures the initial retransmission interval, in seconds, for retransmission after the DNS response timeout. The retransmission interval doubles after each retry when only one server is configured. In case both primary and secondary servers are configured, the retransmission time is doubled for the last retry.
> time: enter an integer from 2 to 5. Default is 3 seconds.
> Usage
> Set the DNS retransmission retries or the retransmission interval. Issue the command twice to configure both parameters, one-at-a-time.
> Example
> The following command sets the DNS resolver retries to 4:
> resolver number-of-retries 4
> round-robin answers
> This command configures the DNS client to return the DNS results in round-robin fashion if multiple results are available for a DNS query.
> Product
> MME, SGSN
> Privilege
> Security Administrator, Administrator
> Syntax
> [ no | default ] round-robin-answers
> no
> Removes the configured round robin method for DNS answer.
> default
> Disabled the round robin method for DNS answer.
> Usage
> Use this command to configure the DNS client to return the DNS results in round-robin fashion if multiple results are available for a DNS query.
> Example
> The following command configures the DNS client to use round robin method for DNS query answers:
> default ] round-robin-answers

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