From 6beeb1b708550be0d4a53b272283e17e5e35fe17 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 17:01:30 +0200 Subject: Adding upstream version 2.4.57. Signed-off-by: Daniel Baumann --- docs/manual/bind.html.en | 246 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 246 insertions(+) create mode 100644 docs/manual/bind.html.en (limited to 'docs/manual/bind.html.en') diff --git a/docs/manual/bind.html.en b/docs/manual/bind.html.en new file mode 100644 index 0000000..1c8567b --- /dev/null +++ b/docs/manual/bind.html.en @@ -0,0 +1,246 @@ + + + + + +Binding to Addresses and Ports - Apache HTTP Server Version 2.4 + + + + + + +
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Apache HTTP Server Version 2.4

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+

Binding to Addresses and Ports

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Available Languages:  de  | + en  | + fr  | + ja  | + ko  | + tr 

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+ +

Configuring Apache HTTP Server to listen on specific addresses and ports.

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Overview

+ + +
Related ModulesRelated Directives
+ + +

When httpd starts, it binds to some port and address on + the local machine and waits for incoming requests. By default, + it listens to all addresses on the machine. However, it may need to + be told to listen on specific ports, or only on selected + addresses, or a combination of both. This is often combined with the + Virtual Host feature, which determines how + httpd responds to different IP addresses, hostnames and + ports.

+ +

The Listen + directive tells the server to accept + incoming requests only on the specified port(s) or + address-and-port combinations. If only a port number is + specified in the Listen + directive, the server listens to the given port on all interfaces. + If an IP address is given as well as a port, the server will listen + on the given port and interface. Multiple Listen directives may be used to + specify a number of addresses and ports to listen on. The + server will respond to requests from any of the listed + addresses and ports.

+ +

For example, to make the server accept connections on both + port 80 and port 8000, on all interfaces, use:

+ + 
Listen 80
+Listen 8000
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+ +

To make the server accept connections on port 80 for one interface, + and port 8000 on another, use

+ + 
Listen 192.0.2.1:80
+Listen 192.0.2.5:8000
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+ +

IPv6 addresses must be enclosed in square brackets, as in the + following example:

+ + 
Listen [2001:db8::a00:20ff:fea7:ccea]:80
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+ +

Overlapping Listen directives will result in a + fatal error which will prevent the server from starting up.

+ +

+ (48)Address already in use: make_sock: could not bind to address [::]:80 +

+ +

See the + discussion in the wiki for further troubleshooting tips.

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Changing Listen configuration on restart

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When httpd is restarted, special consideration must be made for + changes to Listen directives. During a restart, httpd keeps ports + bound (as in the original configuration) to avoid generating + "Connection refused" errors for any new attempts to connect to the + server. If changes are made to the set of Listen directives used + which conflict with the old configuration, configuration will fail + and the server will terminate.

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For example, changing from configuration:

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Listen 127.0.0.1:80
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to the following may fail, because binding to port 80 across + all addresses conflicts with binding to port 80 on just + 127.0.0.1.

+ + 
Listen 80
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+ +

To have such configuration changes take effect, it is necessary + to stop and then start the server.

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Special IPv6 Considerations

+ + +

A growing number of platforms implement IPv6, and + APR supports IPv6 on most of these platforms, + allowing httpd to allocate IPv6 sockets, and to handle requests sent + over IPv6.

+ +

One complicating factor for httpd administrators is whether or + not an IPv6 socket can handle both IPv4 connections and IPv6 + connections. Handling IPv4 connections with an IPv6 socket uses + IPv4-mapped IPv6 addresses, which are allowed by default on most + platforms, but are disallowed by default on FreeBSD, NetBSD, and + OpenBSD, in order to match the system-wide policy on those + platforms. On systems where it is disallowed by default, a + special configure parameter can change this behavior + for httpd.

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On the other hand, on some platforms, such as Linux and Tru64, the + only way to handle both IPv6 and IPv4 is to use + mapped addresses. If you want httpd to handle IPv4 and IPv6 connections + with a minimum of sockets, which requires using IPv4-mapped IPv6 + addresses, specify the --enable-v4-mapped configure option.

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--enable-v4-mapped is the default on all platforms except + FreeBSD, NetBSD, and OpenBSD, so this is probably how your httpd was + built.

+ +

If you want httpd to handle IPv4 connections only, regardless of + what your platform and APR will support, specify an IPv4 address on all + Listen directives, as in the + following examples:

+ + 
Listen 0.0.0.0:80
+Listen 192.0.2.1:80
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+ +

If your platform supports it and you want httpd to handle IPv4 and + IPv6 connections on separate sockets (i.e., to disable IPv4-mapped + addresses), specify the --disable-v4-mapped configure option. --disable-v4-mapped is the + default on FreeBSD, NetBSD, and OpenBSD.

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Specifying the protocol with Listen

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The optional second protocol argument of + Listen + is not required for most + configurations. If not specified, https is the default for + port 443 and http the default for all other ports. The + protocol is used to determine which module should handle a request, and + to apply protocol specific optimizations with the + AcceptFilter directive.

+ +

You only need to set the protocol if you are running on non-standard + ports. For example, running an https site on port 8443:

+ + 
Listen 192.170.2.1:8443 https
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How This Works With Virtual Hosts

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The Listen directive does not implement + Virtual Hosts - it only tells the + main server what addresses and ports to listen on. If no + <VirtualHost> + directives are used, the server will behave + in the same way for all accepted requests. However, + <VirtualHost> + can be used to specify a different behavior + for one or more of the addresses or ports. To implement a + VirtualHost, the server must first be told to listen to the + address and port to be used. Then a + <VirtualHost> section + should be created for the specified address and port to set the + behavior of this virtual host. Note that if the + <VirtualHost> + is set for an address and port that the + server is not listening to, it cannot be accessed.

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Available Languages:  de  | + en  | + fr  | + ja  | + ko  | + tr 

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Comments

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