named.conf.4 (2010 09)

n
named.conf(4) named.conf(4)
(BIND 9.3)
host on the 192.168.4/24 or the 192.168.5/24 network will only prefer other addresses on their directly
connected networks.
sortlist {
{ localhost; // IF the local host
{ localnets; // THEN first fit on the
192.168.1/24; // following nets
{ 192.168.2/24; 192.168.3/24; }; }; };
{ 192.168.1/24; // IF on class C 192.168.1
{ 192.168.1/24; // THEN use .1, or .2 or .3
{ 192.168.2/24; 192.168.3/24; }; }; };
{ 192.168.2/24; // IF on class C 192.168.2
{ 192.168.2/24; // THEN use .2, or .1 or .3
{ 192.168.1/24; 192.168.3/24; }; }; };
{ 192.168.3/24; // IF on class C 192.168.3
{ 192.168.3/24; // THEN use .3, or .1 or .2
{ 192.168.1/24; 192.168.2/24; }; }; };
{ // IF .4 or .5, prefer that net
{ 192.168.4/24; 192.168.5/24; }; };
};
The following example gives reasonable behavior for the local host and hosts on directly connected net-
works. It is similar to the behavior of the address sort in BIND 4.9.x. Responses sent to queries from the
local host will favor any of the directly connected networks. Responses sent to queries from any other
hosts on a directly connected network will prefer addresses on that same network. Responses to other
queries will not be sorted.
sortlist {
{ localhost; localnets; };
{ localnets; };
};
Tuning Options
edns-udp-size
Sets the advertised Extended DNS (EDNS) UDP buffer size in bytes. Valid values are
512 to 4096 (values outside this range will be silently adjusted). The default value is
4096. The usual reason for setting edns-udp-size
to a nondefault value is to get UDP
answers to pass through broken firewalls that block fragmented packets and/or block
UDP packets that are greater than 512 bytes.
lame-ttl Sets the number of seconds to cache a lame server indication. 0 disables caching. (This
is not recommended.) The default is 600 (10 minutes). The maximum value is 1800 (30
minutes). (See the
lame-servers keyword in The Category Phrase section.)
max-cache-ttl
Sets the maximum time in seconds for which the server will cache ordinary (positive)
answers. The default is one week (7 days).
max-ncache-ttl
To reduce network traffic and increase performance, the server stores negative answers.
max-ncache-ttl is used to set a maximum retention time for these answers in the
server in seconds. The default is 10800 seconds (3 hours). The maximum is 7 days and
will be truncated to 7 days if set to a greater value.
max-refresh-time, max-retry-time, min-refresh-time, min-retry-time
These options control the server’s behavior on refreshing a zone (querying for SOA
changes) or retrying failed transfers. Usually the SOA values for the zone are used, but
these values are set by the master, giving slave server administrators little control over
their contents.
These options allow the administrator to set a minimum and maximum refresh and retry
time either per-zone, per-view, or per-server. These options are valid for master, slave
20 Hewlett-Packard Company − 20 − HP-UX 11i Version 3: September 2010