Product Documentation

Configure the Citrix ADC appliance as a forwarder

A forwarder is a server that forwards DNS queries to DNS servers that are outside the forwarder server’s network. Queries that cannot be resolved locally are forwarded to other DNS servers. A forwarder accumulates external DNS information in its cache as it resolves DNS queries. To configure the Citrix ADC appliance as a forwarder, you must add an external name server.

The Citrix ADC appliance allows you to add external name servers to which it can forward the name resolution queries that cannot be resolved locally. To configure the Citrix ADC appliance as a forwarder, you must add the name servers to which it must forward name resolution queries. You can specify the lookup priority to specify the name service that the Citrix ADC appliance must use for name resolution.

Note:

The Citrix ADC appliance in forwarder mode supports TCP, UDP, and UDP-TCP name servers.

  • If you have configured a TCP name server, then the NetSCitrix ADCcaler appliance sends the DNS request over TCP.
  • If you have configured a UDP name server, then the Citrix ADC appliance sends the DNS request over UDP.
  • If you have configured a UDP-TCP name server, then the Citrix ADC appliance sends the DNS request over UDP. However if the truncated bit is set in the DNS response, the appliance sends such DNS requests over TCP.

Configure the Citrix ADC appliance as a forwarder

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