Chapter 5 Settings for Interfaces and Network Services
they are considered primary, secondary, etc.). This option should be used when there is the need to monitor where DNS queries are forwarded to or to create a more complex configuration.
Enable cache for faster response of repeated queries
If this option is on, all responses will be stored in local DNS Forwarder cache. Responses to repeated queries will be much faster (the same query sent by various clients is also considered as a repeated query).
Physically, the DNS cache is kept in RAM. However, all DNS records are also saved in the DnsCache.cfg file (see chapter 23.2). This means that records in DNS cache are kept even after WinRoute Firewall Engine is stopped or WinRoute is disconnected.
Notes:
1.Time period for keeping DNS logs in the cache is specified individually in each log (usually 24 hours).
2.Use of DNS also speeds up activity of the
Clear cache
Click this button to remove all records in the DNS Forwarder’s cache (regardless of their lifetime). This feature can be helpful e.g. for configuration changes,
Use custom forwarding
Use this option to enable settings for forwarding certain DNS queries to other DNS servers.
Enable DNS forwarding
DNS forwarder allows forwarding of certain DNS requests to specific DNS servers. Re- quest forwarding is defined by rules for DNS names or subnets. If a DNS name or a sub- net in a request matches a rule, the request is forwarded to the corresponding DNS server. Requests matching no rule are forwarded to DNS servers in accordance with settings in the DNS forwarding section (see above).
Note: If the simple DNS resolution is enabled (see below), the forwarding rules are ap- plied only if the DNS Forwarder is not able to respond by using the information in the hosts system file and/or by the DHCP lease table.
DNS forwarding can be helpful for example when we intend to use a local DNS server for the local domain (the other DNS queries will be forwarded to the Internet directly — this will speed up the response). DNS forwarder’s settings also play role in configuration of private networks where it is necessary to provide correct forwarding of requests for names in domains of remote subnets (for details, check chapter 21).
Use the Define button to open the dialog for definition of DNS forwarding rules.
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