-- means using gethostbyname(2) and gethostbyaddr(2)
which usually call system's standard resolver of the host.
If RESOLV is not specified, "sys" is disabled if the IP-address of the
host of DeleGate is resolvable by "dns".
If empty value is specified as RESOLV="" then only hosts listed
in HOSTS parameter can be resolved (this could be useful
when you must hide hosts table for security consideration).
Each resolver can be specified with optional argument like follows:
A resolver can be applied to specific queries from specific clients.
The optional queryHostList specifies for which hosts or
addresses the resolver is applied.
The optional clientHostList specifies for which client hosts
the resolver is applied.
Example: selecting DNS servers depending on the inquired host/address
// resolve local hosts with DNS sever at 192.168.1.2:8053
// and resolve others with 192.168.1.1:53
// this can be decomposed into a set of parameters like follows: RESOLV="cache,dns:local-dns:local-hosts,dns:192.168.1.1" HOSTLIST=local-dns:192.168.1.2:8053 HOSTLIST=local-hosts:192.168.*,*.localdomain
Example: selecting resolvers depending on the inquiring (client) DNS host
// queries from local hosts (192.168.*) for "localHosts" are resolved
// with the file "/etc/hosts", others are resolved with the DNS server
Wait the resolver(s) to be ready before the DeleGate starts the
initialization procedure. In the initialization, the result value
of host-name resolution can be used as an important configuration
parameter like ones for access control.
The resolver of the host system may take time to be ready after
the system's reboot, and could be unstable typically when the host
address is assigned by DHCP. Therefore it might be not yet ready
when the DeleGate started.
By default, DeleGate waits for 10 seconds until it can resolve
a host name "WWW.DeleGate.ORG" by the given set of resolvers which
is specified by the RESOLV parameter.
You can specify a more appropriate host name or IP address to be
used to detect the readiness of the resolvers.
This feature can be disabled with RES_WAIT=0.
Specify a DNS server to be used: dnsServer is a host name or an
IP-address of the host name DNS server, which may optionally be
followed by port number, like "host:8053" when the port number
is not standard port(53).
With "dnsServer//socksV5Host", a DNS server
beyond a firewall can be referred through the specified Socks V5 server.
The Socks server is specified by its IP address with an optional port
number like "192.168.1.1:2080".
By default, name servers listed in "resolv.conf" are
added to the list of DNS servers to be used. A special dnsServ
name ".END" disables to adding such name servers. For example,
RES_NS="192.168.1.1,END." means using 192.168.1.1 only regardless of
Specify the ordered set of address families (IPv4 or IPv6) of the address
of the host to be retrieved. The default value "46" means
retrieving IPv4 address first, and if not found, then IPv6 address next.
With "RES_VRFY=", results of reverse look-up of DNS server is verified.
When an IPaddress1 is resolved to Hostname, and when the
Hostname is resolved to IPaddress-list which does not include
the IPaddress1, the verification fail and the result is ignored.