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diff --git a/erts/doc/src/inet_cfg.xml b/erts/doc/src/inet_cfg.xml
index 027fe600d7..0cfcc7905d 100644
--- a/erts/doc/src/inet_cfg.xml
+++ b/erts/doc/src/inet_cfg.xml
@@ -22,7 +22,7 @@
</legalnotice>
- <title>Inet configuration</title>
+ <title>Inet Configuration</title>
<prepared>Peter Andersson</prepared>
<docno></docno>
<date>2004-03-02</date>
@@ -32,374 +32,341 @@
<section>
<title>Introduction</title>
- <p>This chapter tells you how the Erlang runtime system is configured
- for IP communication. It also explains how you may configure it
- for your own particular needs by means of a configuration file.
- The information here is mainly intended for users with special
- configuration needs or problems. There should normally be no need
- for specific settings for Erlang to function properly on a correctly
- IP configured platform. </p>
- <p>When Erlang starts up it will read the kernel variable
- <c><![CDATA[inetrc]]></c> which, if defined, should specify the location and
- name of a user configuration file. Example:</p>
- <p><c><![CDATA[% erl -kernel inetrc '"./cfg_files/erl_inetrc"']]></c></p>
- <p>Note that the usage of a <c><![CDATA[.inetrc]]></c> file, which was
- supported in earlier Erlang versions, is now obsolete.</p>
- <p>A second way to specify the configuration file is to set the
- environment variable <c><![CDATA[ERL_INETRC]]></c> to the full name of the file. Example (bash):</p>
- <p><c><![CDATA[% export ERL_INETRC=./cfg_files/erl_inetrc]]></c></p>
- <p>Note that the kernel variable <c><![CDATA[inetrc]]></c> overrides this environment variable.</p>
+ <p>This section describes how the Erlang runtime system is configured
+ for IP communication. It also explains how you can configure it
+ for your needs by a configuration file.
+ The information is primarily intended for users with special
+ configuration needs or problems. There is normally no need
+ for specific settings for Erlang to function properly on a correctly
+ IP-configured platform.</p>
+
+ <p>When Erlang starts up it reads the Kernel variable
+ <c><![CDATA[inetrc]]></c>, which, if defined, is to specify the location
+ and name of a user configuration file. Example:</p>
+
+ <code type="none"><![CDATA[
+% erl -kernel inetrc '"./cfg_files/erl_inetrc"']]></code>
+
+ <p>Notice that the use of an <c><![CDATA[.inetrc]]></c> file, which was
+ supported in earlier Erlang/OTP versions, is now obsolete.</p>
+
+ <p>A second way to specify the configuration file is to set
+ environment variable <c><![CDATA[ERL_INETRC]]></c> to the full name of
+ the file. Example (bash):</p>
+
+ <code type="none"><![CDATA[
+% export ERL_INETRC=./cfg_files/erl_inetrc]]></code>
+
+ <p>Notice that the Kernel variable <c><![CDATA[inetrc]]></c>
+ overrides this environment variable.</p>
+
<p>If no user configuration file is specified and Erlang is started
- in non-distributed or short name distributed mode, Erlang will use
- default configuration settings and a native lookup method that should
- work correctly under most circumstances. Erlang
- will not read any information from system inet configuration files
- (like /etc/host.conf, /etc/nsswitch.conf, etc) in these modes,
- except for /etc/resolv.conf and /etc/hosts that is read and monitored
- for changes on Unix platforms for the internal DNS client
- <seealso marker="kernel:inet_res">inet_res</seealso>.</p>
+ in non-distributed or short name distributed mode, Erlang uses
+ default configuration settings and a native lookup method that
+ works correctly under most circumstances. Erlang reads no
+ information from system <c>inet</c> configuration files (such as
+ <c>/etc/host.conf</c> and <c>/etc/nsswitch.conf</c>) in these modes,
+ except for <c>/etc/resolv.conf</c> and <c>/etc/hosts</c> that is read and
+ monitored for changes on Unix platforms for the internal DNS client
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>.</p>
+
<p>If Erlang is started in long name distributed mode, it needs to
- get the domain name from somewhere and will read system inet
+ get the domain name from somewhere and reads system <c>inet</c>
configuration files for this information. Any hosts and resolver
- information found then is also recorded, but not
- used as long as Erlang is configured for native lookups. (The
+ information found is also recorded, but not
+ used as long as Erlang is configured for native lookups. The
information becomes useful if the lookup method is changed to
- <c><![CDATA['file']]></c> or <c><![CDATA['dns']]></c>, see below).</p>
- <p>Native lookup (system calls) is always the default resolver method. This
- is true for all platforms except VxWorks and OSE Delta where <c><![CDATA['file']]></c>
- or <c><![CDATA['dns']]></c> is used (in that order of priority).</p>
- <p>On Windows platforms, Erlang will search the system registry rather than
- look for configuration files when started in long name distributed mode. </p>
+ <c><![CDATA['file']]></c> or <c><![CDATA['dns']]></c>, see below.</p>
+
+ <p>Native lookup (system calls) is always the default resolver method.
+ This is true for all platforms, except VxWorks and OSE Delta where
+ <c><![CDATA['file']]></c> or <c><![CDATA['dns']]></c> is used (in that
+ priority order).</p>
+
+ <p>On Windows platforms, Erlang searches the system registry rather than
+ looks for configuration files when started in long name distributed
+ mode.</p>
</section>
<section>
<title>Configuration Data</title>
<p>Erlang records the following data in a local database if found in system
- inet configuration files (or system registry):</p>
- <list type="bulleted">
- <item>Host names and addresses</item>
+ <c>inet</c> configuration files (or system registry):</p>
+
+ <list type="bulleted">
+ <item>Hostnames and host addresses</item>
<item>Domain name</item>
<item>Nameservers</item>
<item>Search domains</item>
<item>Lookup method</item>
</list>
- <p>This data may also be specified explicitly in the user
- configuration file. The configuration file should contain lines
- of configuration parameters (each terminated with a full
- stop). Some parameters add data to the configuration (e.g. host
+
+ <p>This data can also be specified explicitly in the user
+ configuration file. This file is to contain lines
+ of configuration parameters (each terminated with a full stop).
+ Some parameters add data to the configuration (such as host
and nameserver), others overwrite any previous settings
- (e.g. domain and lookup). The user configuration file is always
+ (such as domain and lookup). The user configuration file is always
examined last in the configuration process, making it possible
for the user to override any default values or previously made
settings. Call <c><![CDATA[inet:get_rc()]]></c> to view the state of the
- inet configuration database.</p>
- <p>These are the valid configuration parameters:</p>
- <p></p>
+ <c>inet</c> configuration database.</p>
+
+ <p>The valid configuration parameters are as follows:</p>
+
<taglist>
- <tag><em><c><![CDATA[{file, Format, File}.]]></c></em></tag>
+ <tag><c><![CDATA[{file, Format, File}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[Format = atom()]]></c></p>
<p><c><![CDATA[File = string()]]></c></p>
- <p></p>
- <p>Specify a system file that Erlang should read configuration
- data from. <c><![CDATA[Format]]></c> tells the parser how the file should be
- interpreted: <c><![CDATA[resolv]]></c> (Unix resolv.conf), <c><![CDATA[host_conf_freebsd]]></c>
- (FreeBSD host.conf), <c><![CDATA[host_conf_bsdos]]></c> (BSDOS host.conf),
- <c><![CDATA[host_conf_linux]]></c> (Linux host.conf), <c><![CDATA[nsswitch_conf]]></c>
- (Unix nsswitch.conf) or <c><![CDATA[hosts]]></c> (Unix hosts). <c><![CDATA[File]]></c> should
- specify the name of the file with full path.</p>
- <p></p>
+ <p>Specify a system file that Erlang is to read configuration data from.
+ <c><![CDATA[Format]]></c> tells the parser how the file is to be
+ interpreted:</p>
+ <list type="bulleted">
+ <item><c><![CDATA[resolv]]></c> (Unix resolv.conf)</item>
+ <item><c><![CDATA[host_conf_freebsd]]></c> (FreeBSD host.conf)</item>
+ <item><c><![CDATA[host_conf_bsdos]]></c> (BSDOS host.conf)</item>
+ <item><c><![CDATA[host_conf_linux]]></c> (Linux host.conf)</item>
+ <item><c><![CDATA[nsswitch_conf]]></c> (Unix nsswitch.conf)</item>
+ <item><c><![CDATA[hosts]]></c> (Unix hosts)</item>
+ </list>
+ <p><c><![CDATA[File]]></c> is to specify the filename with full
+ path.</p>
</item>
- <tag><em><c><![CDATA[{resolv_conf, File}.]]></c></em></tag>
+ <tag><c><![CDATA[{resolv_conf, File}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[File = string()]]></c></p>
- <p></p>
- <p>Specify a system file that Erlang should read resolver
+ <p>Specify a system file that Erlang is to read resolver
configuration from for the internal DNS client
- <seealso marker="kernel:inet_res">inet_res</seealso>,
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>,
and monitor for changes, even if it does not exist.
The path must be absolute.</p>
- <p>This may override the configuration parameters
+ <p>This can override the configuration parameters
<c><![CDATA[nameserver]]></c> and
<c><![CDATA[search]]></c> depending on the contents
- of the specified file. They may also change any time in the future
+ of the specified file. They can also change any time in the future
reflecting the file contents.</p>
- <p>If the file is specified as an empty string "",
- no file is read nor monitored in the future. This emulates
- the old behaviour of not configuring the DNS client when
+ <p>If the file is specified as an empty string <c>""</c>,
+ no file is read or monitored in the future. This emulates
+ the old behavior of not configuring the DNS client when
the node is started in short name distributed mode.</p>
- <p>If this parameter is not specified it defaults to
- <c><![CDATA[/etc/resolv.conf]]></c> unless the environment variable
- <c><![CDATA[ERL_INET_ETC_DIR]]></c> is set which defines
+ <p>If this parameter is not specified, it defaults to
+ <c><![CDATA[/etc/resolv.conf]]></c> unless environment variable
+ <c><![CDATA[ERL_INET_ETC_DIR]]></c> is set, which defines
the directory for this file to some maybe other than
<c><![CDATA[/etc]]></c>.</p>
- <p></p>
</item>
- <tag><em><c><![CDATA[{hosts_file, File}.]]></c></em></tag>
+ <tag><c><![CDATA[{hosts_file, File}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[File = string()]]></c></p>
- <p></p>
- <p>Specify a system file that Erlang should read resolver
- configuration from for the internal hosts file resolver
+ <p>Specify a system file that Erlang is to read resolver
+ configuration from for the internal hosts file resolver,
and monitor for changes, even if it does not exist.
The path must be absolute.</p>
<p>These host entries are searched after all added with
<c>{file, hosts, File}</c> above or
- <c>{host, IP, Aliases}</c> below when the lookup option
+ <c>{host, IP, Aliases}</c> below when lookup option
<c>file</c> is used.</p>
- <p>If the file is specified as an empty string "",
- no file is read nor monitored in the future. This emulates
- the old behaviour of not configuring the DNS client when
+ <p>If the file is specified as an empty string <c>""</c>,
+ no file is read or monitored in the future. This emulates
+ the old behavior of not configuring the DNS client when
the node is started in short name distributed mode.</p>
- <p>If this parameter is not specified it defaults to
- <c><![CDATA[/etc/hosts]]></c> unless the environment variable
- <c><![CDATA[ERL_INET_ETC_DIR]]></c> is set which defines
+ <p>If this parameter is not specified, it defaults to
+ <c><![CDATA[/etc/hosts]]></c> unless environment variable
+ <c><![CDATA[ERL_INET_ETC_DIR]]></c> is set, which defines
the directory for this file to some maybe other than
<c><![CDATA[/etc]]></c>.</p>
- <p></p>
</item>
- <tag><em><c><![CDATA[{registry, Type}.]]></c></em></tag>
+ <tag><c><![CDATA[{registry, Type}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[Type = atom()]]></c></p>
- <p></p>
- <p>Specify a system registry that Erlang should read configuration
- data from. Currently, <c><![CDATA[win32]]></c> is the only valid option.</p>
- <p></p>
+ <p>Specify a system registry that Erlang is to read configuration
+ data from. <c><![CDATA[win32]]></c> is the only valid option.</p>
</item>
- <tag><em><c><![CDATA[{host, IP, Aliases}.]]></c></em></tag>
+ <tag><c><![CDATA[{host, IP, Aliases}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[IP = tuple()]]></c></p>
<p><c><![CDATA[Aliases = [string()]]]></c></p>
- <p></p>
<p>Add host entry to the hosts table.</p>
- <p></p>
</item>
- <tag><em><c><![CDATA[{domain, Domain}.]]></c></em></tag>
+ <tag><c><![CDATA[{domain, Domain}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[Domain = string()]]></c></p>
- <p></p>
<p>Set domain name.</p>
- <p></p>
</item>
- <tag><em><c><![CDATA[{nameserver, IP [,Port]}.]]></c></em></tag>
+ <tag><c><![CDATA[{nameserver, IP [,Port]}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[IP = tuple()]]></c></p>
<p><c><![CDATA[Port = integer()]]></c></p>
- <p></p>
- <p>Add address (and port, if other than default) of primary
+ <p>Add address (and port, if other than default) of the primary
nameserver to use for
- <seealso marker="kernel:inet_res">inet_res</seealso>.</p>
- <p></p>
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>.
+ </p>
</item>
- <tag><em><c><![CDATA[{alt_nameserver, IP [,Port]}.]]></c></em></tag>
+ <tag><c><![CDATA[{alt_nameserver, IP [,Port]}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[IP = tuple()]]></c></p>
<p><c><![CDATA[Port = integer()]]></c></p>
- <p></p>
- <p>Add address (and port, if other than default) of secondary
+ <p>Add address (and port, if other than default) of the secondary
nameserver for
- <seealso marker="kernel:inet_res">inet_res</seealso>.</p>
- <p></p>
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>.
+ </p>
</item>
- <tag><em><c><![CDATA[{search, Domains}.]]></c></em></tag>
+ <tag><c><![CDATA[{search, Domains}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[Domains = [string()]]]></c></p>
- <p></p>
<p>Add search domains for
- <seealso marker="kernel:inet_res">inet_res</seealso>.</p>
- <p></p>
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>.
+ </p>
</item>
- <tag><em><c><![CDATA[{lookup, Methods}.]]></c></em></tag>
+ <tag><c><![CDATA[{lookup, Methods}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[Methods = [atom()]]]></c></p>
- <p></p>
- <p>Specify lookup methods and in which order to try them.
- The valid methods are: <c><![CDATA[native]]></c> (use system calls),
- <c><![CDATA[file]]></c> (use host data retrieved from
- system configuration files and/or
- the user configuration file) or <c><![CDATA[dns]]></c>
- (use the Erlang DNS client
- <seealso marker="kernel:inet_res">inet_res</seealso>
- for nameserver queries).</p>
+ <p>Specify lookup methods and in which order to try them.
+ The valid methods are as follows:</p>
+ <list type="bulleted">
+ <item><c><![CDATA[native]]></c> (use system calls)</item>
+ <item><c><![CDATA[file]]></c> (use host data retrieved from system
+ configuration files and/or the user configuration file)</item>
+ <item><c><![CDATA[dns]]></c> (use the Erlang DNS client
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>
+ for nameserver queries)</item>
+ </list>
<p>The lookup method <c><![CDATA[string]]></c> tries to
- parse the hostname as a IPv4 or IPv6 string and return
+ parse the hostname as an IPv4 or IPv6 string and return
the resulting IP address. It is automatically tried
first when <c><![CDATA[native]]></c> is <em>not</em>
- in the <c><![CDATA[Methods]]></c> list. To skip it in this case
+ in the <c><![CDATA[Methods]]></c> list. To skip it in this case,
the pseudo lookup method <c><![CDATA[nostring]]></c> can be
inserted anywhere in the <c><![CDATA[Methods]]></c> list.</p>
- <p></p>
</item>
- <tag><em><c><![CDATA[{cache_size, Size}.]]></c></em></tag>
+ <tag><c><![CDATA[{cache_size, Size}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[Size = integer()]]></c></p>
- <p></p>
- <p>Set size of resolver cache. Default is 100 DNS records.</p>
- <p></p>
+ <p>Set the resolver cache size. Defaults to 100 DNS records.</p>
</item>
- <tag><em><c><![CDATA[{cache_refresh, Time}.]]></c></em></tag>
- <item>
- <p></p>
+ <tag><c><![CDATA[{cache_refresh, Time}.]]></c></tag>
+ <item>
<p><c><![CDATA[Time = integer()]]></c></p>
- <p></p>
- <p>Set how often (in millisec)
- the resolver cache for
- <seealso marker="kernel:inet_res">inet_res</seealso>.
- is refreshed (i.e. expired DNS records are deleted).
- Default is 1 h.</p>
- <p></p>
+ <p>Set how often (in milliseconds) the resolver cache for
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>
+ is refreshed (that is, expired DNS records are deleted).
+ Defaults to 1 hour.</p>
</item>
- <tag><em><c><![CDATA[{timeout, Time}.]]></c></em></tag>
+ <tag><c><![CDATA[{timeout, Time}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[Time = integer()]]></c></p>
- <p></p>
- <p>Set the time to wait until retry (in millisec) for DNS queries
+ <p>Set the time to wait until retry (in milliseconds) for DNS queries
made by
- <seealso marker="kernel:inet_res">inet_res</seealso>.
- Default is 2 sec.</p>
- <p></p>
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>.
+ Defaults to 2 seconds.</p>
</item>
- <tag><em><c><![CDATA[{retry, N}.]]></c></em></tag>
+ <tag><c><![CDATA[{retry, N}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[N = integer()]]></c></p>
- <p></p>
<p>Set the number of DNS queries
- <seealso marker="kernel:inet_res">inet_res</seealso>
- will try before giving up.
- Default is 3.</p>
- <p></p>
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>
+ will try before giving up. Defaults to 3.</p>
</item>
- <tag><em><c><![CDATA[{inet6, Bool}.]]></c></em></tag>
+ <tag><c><![CDATA[{inet6, Bool}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[Bool = true | false]]></c></p>
- <p></p>
- <p>Tells the DNS client
- <seealso marker="kernel:inet_res">inet_res</seealso>
- to look up IPv6 addresses. Default is false.</p>
- <p></p>
+ <p>Tells the DNS client
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>
+ to look up IPv6 addresses. Defaults to <c>false</c>.</p>
</item>
- <tag><em><c><![CDATA[{usevc, Bool}.]]></c></em></tag>
+ <tag><c><![CDATA[{usevc, Bool}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[Bool = true | false]]></c></p>
- <p></p>
- <p>Tells the DNS client
- <seealso marker="kernel:inet_res">inet_res</seealso>
- to use TCP (Virtual Circuit) instead of UDP. Default is false.</p>
- <p></p>
+ <p>Tells the DNS client
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>
+ to use TCP (Virtual Circuit) instead of UDP. Defaults to
+ <c>false</c>.</p>
</item>
- <tag><em><c><![CDATA[{edns, Version}.]]></c></em></tag>
+ <tag><c><![CDATA[{edns, Version}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[Version = false | 0]]></c></p>
- <p></p>
<p>Sets the EDNS version that
- <seealso marker="kernel:inet_res">inet_res</seealso>
- will use. The only allowed is zero. Default is false
- which means to not use EDNS.</p>
- <p></p>
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>
+ will use. The only allowed version is zero. Defaults to <c>false</c>,
+ which means not to use EDNS.</p>
</item>
- <tag><em><c><![CDATA[{udp_payload_size, Size}.]]></c></em></tag>
+ <tag><c><![CDATA[{udp_payload_size, Size}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[N = integer()]]></c></p>
- <p></p>
<p>Sets the allowed UDP payload size
- <seealso marker="kernel:inet_res">inet_res</seealso>
+ <seealso marker="kernel:inet_res"><c>inet_res(3)</c></seealso>
will advertise in EDNS queries. Also sets the limit
when the DNS query will be deemed too large for UDP
- forcing a TCP query instead, which is not entirely
- correct since the advertised UDP payload size of the
- individual nameserver is what should be used,
+ forcing a TCP query instead; this is not entirely
+ correct, as the advertised UDP payload size of the
+ individual nameserver is what is to be used,
but this simple strategy will do until a more intelligent
- (probing, caching) algorithm need be implemented.
- The default is 1280 which stems from the
- standard Ethernet MTU size.</p>
- <p></p>
+ (probing, caching) algorithm needs to be implemented.
+ Default to 1280, which stems from the standard Ethernet MTU size.</p>
</item>
- <tag><em><c><![CDATA[{udp, Module}.]]></c></em></tag>
+ <tag><c><![CDATA[{udp, Module}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[Module = atom()]]></c></p>
- <p></p>
- <p>Tell Erlang to use other primitive UDP module than inet_udp.</p>
- <p></p>
+ <p>Tell Erlang to use another primitive UDP module than
+ <c>inet_udp</c>.</p>
</item>
- <tag><em><c><![CDATA[{tcp, Module}.]]></c></em></tag>
+ <tag><c><![CDATA[{tcp, Module}.]]></c></tag>
<item>
- <p></p>
<p><c><![CDATA[Module = atom()]]></c></p>
- <p></p>
- <p>Tell Erlang to use other primitive TCP module than inet_tcp.</p>
- <p></p>
+ <p>Tell Erlang to use another primitive TCP module than
+ <c>inet_tcp</c>.</p>
</item>
- <tag><em><c><![CDATA[clear_hosts.]]></c></em></tag>
+ <tag><c><![CDATA[clear_hosts.]]></c></tag>
<item>
- <p></p>
<p>Clear the hosts table.</p>
- <p></p>
</item>
- <tag><em><c><![CDATA[clear_ns.]]></c></em></tag>
+ <tag><c><![CDATA[clear_ns.]]></c></tag>
<item>
- <p></p>
<p>Clear the list of recorded nameservers (primary and secondary).</p>
- <p></p>
</item>
- <tag><em><c><![CDATA[clear_search.]]></c></em></tag>
+ <tag><c><![CDATA[clear_search.]]></c></tag>
<item>
- <p></p>
<p>Clear the list of search domains.</p>
- <p></p>
</item>
</taglist>
</section>
<section>
<title>User Configuration Example</title>
- <p>Here follows a user configuration example.</p>
- <p>Assume a user does not want Erlang to use the native lookup method,
- but wants Erlang to read all information necessary from start and use
- that for resolving names and addresses. In case lookup fails, Erlang
- should request the data from a nameserver (using the Erlang
+ <p>Assume that a user does not want Erlang to use the native lookup method,
+ but wants Erlang to read all information necessary from start and use
+ that for resolving names and addresses. If lookup fails, Erlang
+ is to request the data from a nameserver (using the Erlang
DNS client, set to use EDNS allowing larger responses).
- The resolver configuration will be updated when
- its configuration file changes, furthermore, DNS records
- should never be cached. The user configuration file
+ The resolver configuration is updated when
+ its configuration file changes. Also, DNS records
+ are never to be cached. The user configuration file
(in this example named <c><![CDATA[erl_inetrc]]></c>, stored
- in directory <c><![CDATA[./cfg_files]]></c>) could then look like this
+ in directory <c><![CDATA[./cfg_files]]></c>) can then look as follows
(Unix):</p>
+
<pre>
- %% -- ERLANG INET CONFIGURATION FILE --
- %% read the hosts file
- {file, hosts, "/etc/hosts"}.
- %% add a particular host
- {host, {134,138,177,105}, ["finwe"]}.
- %% do not monitor the hosts file
- {hosts_file, ""}.
- %% read and monitor nameserver config from here
- {resolv_conf, "/usr/local/etc/resolv.conf"}.
- %% enable EDNS
- {edns,0}.
- %% disable caching
- {cache_size, 0}.
- %% specify lookup method
- {lookup, [file, dns]}.</pre>
- <p>And Erlang could, for example, be started like this:</p>
- <p><c><![CDATA[% erl -sname my_node -kernel inetrc '"./cfg_files/erl_inetrc"']]></c></p>
+%% -- ERLANG INET CONFIGURATION FILE --
+%% read the hosts file
+{file, hosts, "/etc/hosts"}.
+%% add a particular host
+{host, {134,138,177,105}, ["finwe"]}.
+%% do not monitor the hosts file
+{hosts_file, ""}.
+%% read and monitor nameserver config from here
+{resolv_conf, "/usr/local/etc/resolv.conf"}.
+%% enable EDNS
+{edns,0}.
+%% disable caching
+{cache_size, 0}.
+%% specify lookup method
+{lookup, [file, dns]}.</pre>
+
+ <p>And Erlang can, for example, be started as follows:</p>
+
+ <code type="none"><![CDATA[
+% erl -sname my_node -kernel inetrc '"./cfg_files/erl_inetrc"']]></code>
</section>
</chapter>
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