HP-UX Reference (11i v3 07/02) - 4 File Formats (vol 8)

n
named.conf(4) named.conf(4)
(BIND 9.3)
tcp-clients
The maximum number of simultaneous client TCP connections that the server will accept.
The default is 100.
tcp-listen-queue
The listen queue depth. The default and minimum is 3. If the kernel supports the accept
filter "dataready", this also controls how many TCP connections that will be queued in ker-
nel space waiting for some data before being passed to accept. Values less than 3 are
silently raised.
Sorting Option
The response to a DNS query may consist of multiple resource records (RRs) forming a resource records set
(RRset). The name server will normally return the RRs within the RRset in an indeterminate order (but
see the rrset-reorder
statement in the RRset Reordering Option section). The client resolver code
should rearrange the RRs as appropriate, that is, using any addresses on the local net in preference to
other addresses. However, not all resolvers can do this or are correctly configured. When a client is using
a local server, the sorting can be performed in the server, based on the client’s address. This only requires
configuring the name servers, not all the clients.
The
sortlist option takes an address_match_list and interprets it. Each top level statement in the
sortlist must itself be an explicit address_match_list with one or two elements. The first element
(which may be an IP address, an IP prefix, an ACL name, or a nested address_match_list) of each top level
list is checked against the source address of the query until a match is found.
Once the source address of the query has been matched, if the top level statement contains only one ele-
ment, the actual primitive element that matched the source address is used to select the address in the
response to move to the beginning of the response. If the statement is a list of two elements, then the
second element is interpreted in a special way. Each top level element is assigned a distance and the
address in the response with the minimum distance is moved to the beginning of the response.
In the following example, any queries received from any of the addresses of the host itself will get
responses preferring addresses on any of the locally connected networks. Next will be addresses on the
192.168.1/24 network, and after that either the 192.168.2/24 or 192.168.3/24 network with no preference
shown between these two networks. Queries received from a host on the 192.168.1/24 network will prefer
other addresses on that network to the 192.168.2/24 and 192.168.3/24 networks. Queries received from a
host on the 192.168.4/24 or the 192.168.5/24 network will only prefer other addresses on their directly con-
nected 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.
HP-UX 11i Version 3: February 2007 − 19 − Hewlett-Packard Company 251