5.3 DNS Forwarder
Figure 5.10 Specific settings of DNS forwarding
DNS server can be specified for:
•DNS name — queries requiring names of computers will be forwarded to this DNS server (so called A queries)
•a subnet — queries requiring IP addresses of the particular domain will be forwarded to the DNS server (reverse domain — PTR queries)
Click on the Add or the Edit button to open a dialog where custom DNS forwarding rules can be defined.
•The Name DNS query option allows specification of a rule for name queries. Use the If the queried name matches entry to specify a corresponding DNS name (name of a host in the domain).
It is usually desirable to forward queries to entire domains rather than to specific names. Specification of a domain name may therefore contain * wildcard symbol (asterisk — substitutes any number of characters) and/or ? (question mark — sub- stitutes a single character). The rule will be applied to all names matching with the string (hosts, domains, etc.).
Example: DNS name will be represented by the string ?erio.c*. The rule will be applied to all names in domains kerio.cz, cerio.com, aerio.c etc., such as on www.kerio.cz, secure.kerio.com, www.aerio.c, etc.
Warning: It is necessary that the expression specified in the If the query contains domain entry is an entire DNS name! If, for example, the kerio.c* expression is introduced, only names kerio.cz, kerio.com etc. would match the rule and host names included in these domains (such as www.kerio.cz and secure.kerio.com) would not!
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