Name resolution in DNS Filter server is accomplished by forwarding DNS requests (DNS forwarding) to an upstream server. Responses to DNS requests are cached in RAM to make name resolution faster during repeat requests. To disable DNS caching, set dns_cache_enable=0 in the server settings file. The maximum quantity of entries that can be stored in the programs DNS cache is set in cache_size parameter located in section of the settings file. The default cache size is maximum 500 entries. One of the additional parameters you can set on DNS Setup page is the cached entry lifetime (parameters max_cache_pos_ttl and max_cache_neg_ttl).
To configure DNS in the administration console, go to Services DNS Setup. You may list one or more serversin the settings where DNS Filter will send client requests. By default, DNS Filter will use the DNS server listed in the network settings of the computer where the application is installed.
Figure 1 DNS Setup