From 3dc1a039b355380451dd382b58c9b7c2e07788c2 Mon Sep 17 00:00:00 2001 From: Brian Wellington Date: Mon, 6 Nov 2000 22:18:52 +0000 Subject: [PATCH] Document the lwres configuration mechanisms. --- doc/arm/Bv9ARM-book.xml | 77 ++++++++++++++++++++++++++++++++++------- 1 file changed, 65 insertions(+), 12 deletions(-) diff --git a/doc/arm/Bv9ARM-book.xml b/doc/arm/Bv9ARM-book.xml index 43dc959842..da0938908d 100644 --- a/doc/arm/Bv9ARM-book.xml +++ b/doc/arm/Bv9ARM-book.xml @@ -2,7 +2,7 @@ - + @@ -1603,24 +1603,35 @@ using a combination of a lightweight resolver library and a resolver daemon process running on the local host. These communicate using a simple UDP-based protocol, the "lightweight resolver protocol" that is distinct from and simpler than the full DNS protocol. -Running a Resolver Daemon +Running a Resolver Daemon To use the lightweight resolver interface, the system must run the resolver daemon lwresd. -Applications using the lightweight resolver library will make -UDP requests to the IPv4 loopback address (127.0.0.1) on port 921. - The daemon will try to find the answer to the questions "what are the -addresses for host foo.example.com?" and "what are -the names for IPv4 address 204.152.184.79?" +By default, applications using the lightweight resolver library will make +UDP requests to the IPv4 loopback address (127.0.0.1) on port 921. The +address can be overriden by lwserver lines in +/etc/resolv.conf. +The daemon will try to find the answer to the questions "what are the +addresses for host +foo.example.com?" and "what are +the names for IPv4 address 10.1.2.3?" The daemon currently only looks in the DNS, but in the future -it may use other sources such as /etc/hosts, +it may use other sources such as /etc/hosts, NIS, etc. -The lwresd daemon is essentially a stripped-down, +The lwresd daemon is essentially a caching-only name server that answers requests using the lightweight resolver protocol rather than the DNS protocol. Because it needs to run on each host, it is designed to require no or minimal configuration. - It uses the name servers listed on nameserver lines -in /etc/resolv.conf as forwarders, but is also -capable of doing the resolution autonomously if none are specified. +Unless configured otherwise, it uses the name servers listed on +nameserver lines in /etc/resolv.conf +as forwarders, but is also capable of doing the resolution autonomously if +none are specified. +The lwresd daemon may also be configured with a +named.conf style configuration file, in +/etc/lwresd.conf by default. A name server may also +be configured to act as a lightweight resolver daemon using the +lwres{} statement in named.conf. + + <acronym>BIND</acronym> 9 Configuration Reference BIND 9 configuration is broadly similar to BIND 8.x; however, @@ -2354,6 +2365,48 @@ lookups performed on behalf of clients by a caching name server. + + <command>lwres</command> Statement Grammar + + This is the grammar of the lwres + statement in the named.conf file: +lwres + listen-on { address_match_list }; + view view_name; + search { domain_name ; ip_addr ; ... }; + ndots number; + + + <command>lwres</command> Statement Definition and Usage + + The lwres statement configures the name + server to also act as a lightweight resolver server, see + . There may be be multiple + lwres statements configuring + lightweight resolver servers with different properties. + + The listen-on statement specifies a list of + addresses (and ports) that this instance of a lightweight resolver daemon + should accept requests on. If this statement is omitted, requests + will be accepted on 127.0.0.1, port 53. + + The view statement binds this instance of a + lightweight resolver daemon to a view in the DNS namespace, so that the + response will be constructed in the same manner as a normal DNS query + matching this view. If this statement is omitted, the default view is + used, and if there is no default view, an error is triggered. + + The search statement is equivalent to the + search statement in + /etc/resolv.conf. It provides a list of domains + which are appended to relative names in queries. + + The ndots statement is equivalent to the + ndots statement in + /etc/resolv.conf. It indicates the minimum + number of dots in a relative domain name that should result in an + exact match lookup before search path elements are appended. + <command>options</command> Statement Grammar