options
option [
option] ...
The options entry is used to define the behavior of a number of resolver routines by the values specified for option.
The following values can be specified for option:
debug
This activates the diagnostic mechanism of the DNS resolver daemon, and diagnostic messages are written to the /var/adm/syslog file.
ndots:n
Specifies the lower threshold value for the number of dots (“.”) which a name transferred in a DNS request must contain for a first absolute (“as-is”) request to the DNS name server to be executed.
The default is ndots:1
. Thus if a name in a request to the DNS name server contains at least one dot, this name is first of all treated as an absolute name in a request before it is supplemented by domain names (see also the domain entry on "domain entry").
attempts:n
Specifies the maximum number of connection attempts which can be made to each DNS name server per DNS request. The specification attempts:0
has the same effect as the specification attempts:1
.
The default is attempts:4
timeout:n
Specifies the start timeout value for a retransmission in seconds. The previous timeout value is doubled with every attempt until the maximum number of connection attempts (see the attempts parameter) has been made. The specification timeout:0
has the same effect as the specification timeout:1
.
The default is timeout:5.
When the default values for attempts and timeout are used, the overall timeout value for each DNS server is as follows:
5+10+20+40=75 seconds.
rotate
The requests are sent in time slicing mode to the DNS name server generated with the aid of the nameserver entry. Thus instead of letting all clients send their first request to the first DNS server listed, the request volume is distributed evenly over all the listed DNS name servers.
no_tld_query
Causes the DNS resolver not to search for the name of the top level domain, in other words for a name which contains no dots (“.”). Using this option does not prevent the DNS resolver from applying the rules in accordance with a domain or search entry.