Table of Contents

This edition of the JOH User Manual, last updated 31 March 2011, documents JOH Version 1.3.

1. Introduction

Most site administrators use firewalls to protect their network from eventual abuse. Quite often such firewalls do not allow outbound connections to unknown and unused ports, including Jabber client connection port 5222/tcp, which makes it impossible to use Jabber services from inside such firewalls.

Several methods have been proposed so far to overcome this difficulty. The most reliable of them is Jabber HTTP Polling(1), which enables access to Jabber ports via HTTP requests.

Yet another method of accessing Jabber via HTTP is HTTP Connect. This method uses the HTTP ‘CONNECT’ command to establish a permanent connection to the remote Jabber server.

JOH supports both methods. The name JOH stands for Jabber Over HTTP. The package provides an easy to use proxy server for Jabber connections. It is intended for use by system administrators who wish to provide access to their Jabber serves via HTTP for those users who happen to be behind strict firewalls.

2. Quick Start

There are two most common scenarios for configuring Jabber Over HTTP proxy.

In the first scenario, you have a dedicated Jabber server and the port 80 (HTTP) is not used on that server. In this case you will use standalone mode. In this mode johd is configured to listen on port 80 to proxy incoming requests to your Jabber server and vice-versa.

In the second scenario, the port 80 is already in use by an HTTP server running on the same box as your Jabber server. For such cases, JOH provides a CGI mode. In this mode, you start johd to listen on an auxiliary port, and configure your HTTP server to run a CGI program, joh.cgi, which is included in the package. The system then works as follows. HTTP polling requests are received by your HTTP server, which invokes joh.cgi to handle them, In its turn, joh.cgi extracts the necessary data from each request, reformats it and sends it over to the johd daemon over the auxiliary port. When a subsequent request arrives, joh.cgi receives the reply from johd, formats it as a HTTP response and sends it back to the HTTP server, which sends it to the requesting client.

The CGI mode works only with HTTP Polling.

Of course, there may be combined cases, e.g.:

2.1 Configure johd Sockets

Johd reads its configuration from the command line. Only the traditional short options are used. The order in which you place options is important: some of them affect others that appear further in the command line.

The ‘-l’ option configures a socket to listen on (hence its mnemonics: listen). Its argument is an URL or address specification for the socket. Normally, this specification is the desired IP address and port number, separated by a colon. For example, to have johd listen on IP address, port 1111, you would write:

johd -l

If you wish it to listen on a given port on all configured network interfaces, just specify that port alone, without a specific IP address, as in:

johd -l 1111

In fact, Johd is able to work with three distinct socket families: UNIX sockets, IPv4 and IPv6 inet addresses. There are various ways to specify these. For a detailed discussion of them, see URLs.

Any number of ‘-l’ options can be given: johd will open all required sockets and will listen for connections on any of them.

The important point is the class of the socket to open. As you already know, johd works with two distinct socket classes: HTTP sockets, which are supposed to receive data formatted in accordance with the HTTP protocol, and auxiliary CGI sockets, which are designed to communicate with joh.cgi. By default, the latter is assumed(2). The class of the socket to open is changed by the ‘-c’ command line option: ‘-c HTTP’ tells johd to open all subsequent sockets for listening on HTTP requests, and ‘-c CGI’ instructs it to open them for handling internal CGI protocol data. The ‘-c’ option affects all ‘-l’ options that appear to the right of it in the command line, until another ‘-c’ option is encountered, which changes the default. To illustrate this, consider the following invocation:

johd -l \
     -c HTTP -l -l \
     -c CGI

It opens two sockets for auxiliary CGI: one at (it appeared before the first ‘-c’ option and therefore belongs to the default class, which is ‘CGI’) and the other at, which appears after an explicit ‘-c CGI’. Notice that this later has no port specification. If the port is missing. johd will select the default port for this class. The default port for ‘CGI’ is 1100(3), and the default for ‘HTTP’ is, of course, 80. Therefore, the command above will listen for HTTP requests on and

Each incoming connection is validated via TCP wrappers(4). The default daemon (or service) name for validation coincides with the name johd was invoked with (i.e. is ‘johd’, unless you renamed the program or started it via a symlink). However, the validation rules will most probably depend on the class of socket that received the connection: internal ‘CGI’ sockets in most cases should not be visible outside your host, whereas ‘HTTP’ ones should be accessible to everybody, Therefore, a special option is provided, which changes the TCP wrapper service name for subsequent sockets. This is the ‘-S’ option (mnemonics: Service name). Similarly to ‘-c’, the ‘-S’ option affects all ‘-l’ options to the right of it, until another ‘-S’ option or end of the command line is encountered, whichever occurs first.

Now, let's illustrate this by an improved version the example above:

johd -l \
     -S johd-http -c HTTP -l -l \
     -s johd-cgi -c CGI

In this configuration, the socket will be protected by the TCP service name ‘johd’, the two ‘HTTP’ sockets — by service name ‘johd-http’ and the ‘CGI’ socket — by service name ‘johd-cgi’.

Connections to remote Jabber servers are also validated using TCP wrappers. However, they use different service name. The service name for validating a requested jabber connection is created using the following pattern:


where srvname is the TCP service name, as described above, and ipaddr is the IP address of the server.

2.2 Using JOH in Standalone Mode

Configuring johd to work in standalone mode is pretty straightforward: all you have to do is give it an address (or addresses) to listen on and instruct it to open these addresses in ‘HTTP’ class. In a simplest case, the following command will do:

johd -c HTTP

It will instruct johd to listen on port 80 on all configured network interfaces. To select a particular address or addresses to listen on, use the ‘-l’ option, as described in the previous section.

It is important to configure your ‘/etc/hosts.allow’ to control accesses to the incoming HTTP port and outgoing Jabber connections. For example, the two lines below allow access to HTTP from anywhere and grant anybody the right to request any Jabber servers:

johd: ALL
johd/jabber@ALL: ALL

As a more complex example, the entries below allow access to HTTP from anywhere and limit the use of Jabber servers to and The use of is granted to anybody, and the use of is allowed only for clients coming from IP addresses in the range —

johd: ALL
johd/jabber@ ALL

2.3 Using JOH in CGI Mode

The ‘CGI’ mode is a bit more complicated, because it involves configuring two components. However, the default settings are chosen so as to simplify the configuration. First, select the socket to use for interprocess communication between johd and joh.cgi. If both processes run on the same box, then ‘localhost’ or some UNIX socket is a natural choice. Now, start the daemon:

johd -l

Make sure the socket is accessible from localhost. In particular, if your ‘/etc/hosts.deny’ contains the line ‘ALL: ALL’, place this in your ‘/etc/hosts.allow’:


Similarly, make sure outgoing connections to selected Jabber servers are allowed for localhost:


Then copy joh.cgi to your ‘cgi-bin’ directory and you're done. You might also wish to configure your HTTP server to use some good-looking alias for that. For example, in my Apache configuration I use:

Alias /http-poll  /var/www/cgi-bin/joh.cgi

If your HTTP server and johd are running on different machines, you will need to inform joh.cgi about the address johd is listening on. Suppose, for example, that johd is running on machine ‘A’ and is listening on IP address, port 1100. The HTTP server is running on the machine ‘B’, which has IP address To tell joh.cgi it must connect to ‘’, set the environment variable JOH_SERVER_URL. For example, if ‘B’ is running Apache, then in your ‘httpd.conf’ you would set:


Notice also, that you need to ensure that this socket on the box ‘A’ is accessible only to For example:

  1. In ‘/etc/hosts.deny’:
    johd: ALL
  2. In ‘/etc/hosts.allow’:

2.4 Two Ways to Start johd

One of the basic assumptions made when designing johd was that it was to be run as a transport within Jabber configuration. Therefore, after startup, johd remains in the foreground and does not disconnect from the controlling terminal. It also normally sends all its diagnostic messages to the standard error output (but see section Logging and Debugging, below.

To start jabber2 components we recommend using GNU Pies, instead of the default simple program manager shipped with Jabberd2. Pies offers considerable flexibility in handling jabber components. For a detailed description of Pies, GNU Pies Manual: (pies)Top section `Top' in GNU Pies Manual. For an example of Jabberd2 configuration with Pies, refer to

To configure Pies to start johd, add the following component statement to your configuration file:

component johd {
  command "johd options";
  strderr syslog err;

Replace johd with the full pathname of the johd binary, and options with the desired command line options. For example:

component johd {
  command "/usr/sbin/johd -c HTTP";
  strderr syslog err;

Another way to start johd is independently of the Jabber server. To do so, give it the ‘-D’ command line option. This option instructs johd to disconnect from the controlling terminal and run in the background as a daemon. Diagnostic messages are then sent to the syslog, using the ‘daemon’ facility (this can be changed using the ‘-F’ option; see section Logging and Debugging).

Normally, johd continues its operation with the privileges of the user who started it. If this user is root, you may wish johd to run as some other user. To do so, use the ‘-u’ option, e.g.:

johd -cHTTP -D -u nobody

The daemon switches to new user after completing operations that require root privileges, such as, e.g. creating sockets that listen on ports below 1024, etc.

When starting johd in daemon mode, it is also common to give it the ‘-p’ option. This option takes a file name as argument and causes the program to write its PID to that file after switching to the background. If this file already exists, johd will read the PID from it and will check if a process with that PID is actually running. If so, johd refuses to startup and outputs an appropriate diagnostics. Otherwise, it will overwrite the file with the new PID value.

If both ‘-u’ and ‘-p’ are used, the pidfile is opened after switching to the user provileges. In this case, you should make sure the directory component of the pidfile is writable for the user supplied with the ‘-u’ option.

Following is an example startup command:

johd -D -p /var/run/

To automate startup and shutdown of johd in daemon mode, use the following shell script:

#! /bin/sh

case $1 in
start) /usr/bin/johd -D -p $PIDFILE;;
stop)  test -f $PIDFILE && kill -TERM `cat $PIDFILE`;;
       $0 stop
       $0 start;;
*)     echo >&2 "usage: $0 {start|stop|restart}"

2.5 HTTP GET Requests

Proxying of Jabber connections is requested by HTTP requests with either ‘POST’ or ‘CONNECT’ methods. Any other requests received by johd are normally dropped. However, ‘GET’ requests are handled separately. Normally, an incoming ‘GET’ request means that someone has pointed his web browser to the URL served by johd. When such a request arrives, johd replies with a 404 response code. A compiled-in error page is sent back in the response. This behavior can be customized in two ways.

First, you can supply a custom error page using the ‘-E’ command line option. The argument to this option must specify an absolute pathname to a valid HTML file. The contents of this file will be sent back in 404 responses.

Similarly to ‘-c’ and ‘-S’ options, the ‘-E’ option applies to all HTTP sockets created by subsequent ‘-l’ options which appear to the right of it, until another ‘-E’ or ‘-R’ option (see below) is encountered.

An example usage follows:

johd -c HTTP -E /etc/joh/404.html -l

Another way to handle ‘GET’ requests is to return a 303 response, redirecting the requester to another HTTP resource. This is achieved via the ‘-R’ option. Its argument is a valid URL, beginning with a ‘http://’. For example:

johd -c HTTP -R

Notice, that ‘-E’ and ‘-R’ options are mutually exclusive. For example, the following invocation will reply to ‘GET’ requests arriving to ‘’ with the error page read from ‘/etc/joh/404.html’, and will redirect any ‘GET’ request arriving to ‘’ to <>:

johd -c HTTP -E /etc/joh/404.html -l \
     -R -l

The ‘joh.cgi’ utility provides similar features, except that it cannot send back a ‘404’ response.

If any request other than ‘POST’ arrives, ‘joh.cgi’ replies with the compiled-in error page, just as johd does. If the JOH_ERROR_PAGE environment variable is set, and its value points to a readable file, this file's contents is sent back instead.

If JOH_ERROR_REDIRECT variable is set and its value is a URL which begins with ‘http://’, joh.cgi responds with a redirection to that URL.

2.6 Logging and Debugging

Normally, johd prints any errors, warnings and other diagnostic messages on standard error. You can, however, change this default and direct all diagnostic messages to syslog. To do so, specify the desired syslog facility with the ‘-F’ command line option. For example:

johd -F daemon

Allowed facility names for use with this option are: ‘user’, ‘daemon’, ‘auth’, ‘authpriv’, ‘mail’, ‘cron’, ‘local0’ through ‘local7’. All names are case-insensitive.

Notice, that when given the ‘-D’ option (see daemon), johd automatically assumes ‘-F daemon’, so you need not use the ‘-F’ option, unless, of course, you want to change the default facility.

Messages sent to syslog are prefixed by the program name. To change this prefix use the ‘-L’ option. Its argument will be used as a log tag to prefix each message with.

Each diagnostic message has a severity level associated with it. Severity levels are (in order of increasing severity): ‘debug’, ‘warning’, ‘info’, ‘error’, and ‘crit’. The latter is assigned to conditions which cause immediate termination of the program.

Normally, severity levels are not printed. To instruct johd to precede each message with its severity level, use the ‘-P’ option.

Debugging diagnostics is useful when you trace some difficult configuration problem or investigate a bug in johd itself. This diagnostics is printed only when the ‘-d’ option is given. The argument to the ‘-d’ option is the debugging level, an integer number ranging from 0 to 100. Level 0 effectively disables all debugging and is equivalent to not specifying ‘-d’ option at all. Subsequent levels produce increasing amount of debugging information. Finally, the level 100 prints dumps of network packets received and sent by johd.

Notice, that the use of the ‘-d’ option with levels greater than 10 requires a good knowledge about johd internals and slows down its operation, so use it sparingly, if at all.

When debugging johd it may be helpful to know where precisely in the source code each debugging message was generated. This information can be obtained using the ‘-i’ (source-info) option. When it is given, each debug message is additionally prefixed with the name of the source file and line number in it.

3. Johd – Jabber Over HTTP Daemon

The following table summarizes the available command line options in alphabetic order. For each option, it provides a reference to the place in the tutorial where the option is discussed.

-c class

Sets socket class. Allowed values for class are ‘CGI’ and ‘HTTP’. This option affects all subsequent ‘-l’ options appearing to the right of it, until another ‘-c’ option or end of command line is encountered, whichever occurs first.

See socket class.


After startup, switch to the background and run as daemon. See daemon.

-d number

Sets debugging level. See section Logging and Debugging.

-E file

Read the 404 error page from file. This error page is returned as a response to HTTP GET requests. The file must contain a valid HTML document without external references in the ‘head’ section. See section HTTP GET Requests.

This option affects all HTTP sockets created by subsequent ‘-l’ options which appear to the right of it, until another ‘-E’ option or end of command line is encountered, whichever occurs first.

-F facility

Sets syslog facility. Allowed values for facility are: ‘user’, ‘daemon’, ‘auth’, ‘authpriv’, ‘mail’, ‘cron’, ‘local0’ through ‘local7’. All names are case-insensitive.

See section Logging and Debugging.


Shows a terse help summary.


Show source line information with debug messages. See section Logging and Debugging.

-L string

Sets log tag. See section Logging and Debugging.

-l url

Listen on the given url. Several ‘-l’ options can appear in the command line.

See listen option.


Prefix diagnostic messages with their severity level. See section Logging and Debugging.

-p file

Write PID to file. See daemon.

-R url

Redirect HTTP GET requests to url. The argument must begin with ‘http://’. See section HTTP GET Requests.

This option affects all HTTP sockets created by subsequent ‘-l’ options which appear to the right of it, until another ‘-R’ option or end of command line is encountered, whichever occurs first.

-S name

Sets service name for TCP wrappers. This option affects all subsequent ‘-l’ options appearing to the right of it, until another ‘-S’ option or end of command line is encountered, whichever occurs first.

See TCP wrappers.

-s url

Sets URL of the default jabber server. It is used if the request does not specify the server explicitly.

-t type:timeout

Sets session idle timeout. Type is the type of the socket: ‘C’ for client sockets (either ‘CGI’ or ‘HTTP’) and ‘J’ for Jabber socket. Timeout is the timeout value, either in seconds or in ‘XhYmZs’ form.

Defaults are: ‘-t C:5m -t J:1m’.

-u user

Run as user, after completing privileged operations, such as creating sockets that listen on ports below 1024. See daemon.


Prints the program version.

3.1 URLs

JOH components are able to handle three socket families: UNIX sockets, IPv4 and IPv6. URLs provide a uniform way of specifying socket addresses in any of these families.

A URL consists of the following parts:


Up to two parts can be omitted, if that does not create ambiguity.

Valid URL schemes are:


Specifies a UNIX socket. The address part is the socket pathname, and the ‘:port’ part is not used. The pathname must be absolute, e.g. ‘unix:///var/run/joh.socket’.

To facilitate typing, the two slashes after the colon can be omitted, as in:


Specifies an IPv4 socket. The address part must be an IPv4 address in dotted quad form, or a host name. If the latter resolves to multiple addresses, those belonging to the IPv4 family are selected. The port part is either the network port number in decimal, or a corresponding service name from ‘/etc/services’. For example:


Specifies an IPv6 socket. The address part must be either an IPv6 address in numeric notation enclosed in square brackets or a host name. If the latter resolves to multiple addresses, those belonging to the IPv6 family are selected. The port part is either the network port number in decimal, or a corresponding service name from ‘/etc/services’. E.g.:


For URLs given as argument to the ‘-l’ option, either address or port can be omitted. If address is omitted, the program will listen on all available network interfaces with addresses from the specified family, e.g.:


instructs johd to listen on port 1100 on all IPv6 interfaces.

If port is omitted, the default is selected depending upon the class of the socket: 1100 is used for ‘CGI’ sockets, and 80 is used for ‘HTTP’ sockets.

The port component can also be omitted in URLs which are arguments to the ‘-s’ option (see default jabber server). In this case, port defaults to 5222, e.g.:


For compatibility with earlier versions, johd accepts IPv6 addresses without square brackets, although such use is not recommended, e.g.:


If the scheme part is omitted, johd tries to do its best to guess what address family is assumed. Thus:

/var/run/socket’ is treated as ‘unix:///var/run/socket’;’ is treated as ‘inet://’;

[::1]:3398’ is treated as ‘inet6://[::1]:3398’;

::1:3398’ is treated as ‘inet6://[::1]:3398’;

The URL ‘3456’ causes johd to listen on port 3456 on all available network interfaces, no matter what their address family is.

3.2 Exit Codes

Depending on the reason for termination, johd exits with the following codes:


Normal termination. This includes, e.g., termination on ‘SIGTERM’ signal.


Usage error, e.g. unknown option or erroneous argument was given in the command line.


A service is unavailable. This happens, for instance, if the program could not fork or disconnect from the controlling terminal.


An internal software error has been detected. If it ever happens, please report this as bug. See section How to Report a Bug.


Temporary error condition. Currently this happens if the ‘-p file’ option is specified, file exists, but cannot be accessed.


A configuration error occurred. This is different from usage error (64) in that the data supplied to the program where syntactically correct, but cannot be used. For example, a host name supplied with ‘-l’ cannot be resolved.

3.3 Signals

The following signals cause immediate program termination with exit code 0: ‘SIGPIPE’, ‘SIGINT’, ‘SIGQUIT’, ‘SIGTERM’, ‘SIGHUP’.

4. Joh.cgi – Auxiliary CGI Utility

If you need to run johd on a box which already runs an HTTP server, it is impossible to have johd handle HTTP connections directly, because port 80 is already in use. The solution then is to use joh.cgi within your HTTP server and to start johd in CGI mode. This approach is discussed in detail in CGI Mode.

The usual way to run joh.cgi is to copy it to your ‘cgi-bin’ directory and to provide an alias for it. For example, in Apache ‘httpd.conf’:

Alias /http-poll  /var/www/cgi-bin/joh.cgi

The built-in default configuration is sufficient for most cases. If, however, you need to configure joh.cgi, you can do so via the following environment variables:


Sets the URL of the johd server. Default is ‘’.


Sets the URL of the default Jabber server. This value is used when the incoming HTTP request does not specify server and port explicitly.

The default value is ‘inet://’.


Specifies the IP address of the default Jabber server.


Sets the port name of the default Jabber server.


If any request other than ‘POST’ arrives, return the contents of the file specified in the value of this variable. See joh.cgi bad request handling.


If any request other than ‘POST’ arrives, redirect it to the URL supplied in this variable. See joh.cgi bad request handling.

5. How to Report a Bug

Please, report bugs and suggestions to

You hit a bug if at least one of the conditions below is met:

If you think you've found a bug, please be sure to include maximum information available to reliably reproduce it, or at least to analyze it. The information needed is:

Any errors, typos or omissions found in this manual also qualify as bugs. Please report them, if you happen to find any.

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A.1 ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:

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  Permission is granted to copy, distribute and/or modify this document
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  Texts.  A copy of the license is included in the section entitled ``GNU
  Free Documentation License''.

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with...Texts.” line with this:

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If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.

Concept Index

This is a general index of all issues discussed in this manual

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A   C   D   E   F   G   H   I   J   L   P   R   S   T   U   V  
Index Entry Section
/etc/hosts.allow2.2 Using JOH in Standalone Mode
alias, HTTP server2.3 Using JOH in CGI Mode
c, -c class3. Johd – Jabber Over HTTP Daemon
c, -c option introduced2.1 Configure johd Sockets
cgi mode2.3 Using JOH in CGI Mode
CGI mode, defined2. Quick Start
class, socket2.1 Configure johd Sockets
controlling terminal2.4 Two Ways to Start johd
D, -D3. Johd – Jabber Over HTTP Daemon
d, -d number3. Johd – Jabber Over HTTP Daemon
d, -d option, described2.6 Logging and Debugging
D, -D option, introduction2.4 Two Ways to Start johd
daemon mode, johd2.4 Two Ways to Start johd
daemon name, TCP wrappers2.1 Configure johd Sockets
debugging2.6 Logging and Debugging
E, -E file3. Johd – Jabber Over HTTP Daemon
E, -E option, introduction2.5 HTTP GET Requests
exit codes3.2 Exit Codes
F, -F facility3. Johd – Jabber Over HTTP Daemon
F, -F option, described2.6 Logging and Debugging
facility, syslog2.6 Logging and Debugging
FDL, GNU Free Documentation LicenseA. GNU Free Documentation License
firewall1. Introduction
GNU Pies2.4 Two Ways to Start johd
h, -h3. Johd – Jabber Over HTTP Daemon
hosts.allow2.2 Using JOH in Standalone Mode
hosts.allow, CGI sockets2.3 Using JOH in CGI Mode
HTTP Connect1. Introduction
HTTP Polling1. Introduction
i, -i3. Johd – Jabber Over HTTP Daemon
i, -i option described2.6 Logging and Debugging
inet3.1 URLs
inet63.1 URLs
IPv4 sockets3.1 URLs
IPv6 sockets3.1 URLs
jabber22.4 Two Ways to Start johd
joh.cgi4. Joh.cgi – Auxiliary CGI Utility
joh.cgi, described2.3 Using JOH in CGI Mode
JOH_ERROR_PAGE4. Joh.cgi – Auxiliary CGI Utility
JOH_ERROR_REDIRECT4. Joh.cgi – Auxiliary CGI Utility
JOH_JABBER_PORT4. Joh.cgi – Auxiliary CGI Utility
JOH_JABBER_SERVER4. Joh.cgi – Auxiliary CGI Utility
JOH_JABBER_SERVER_URL4. Joh.cgi – Auxiliary CGI Utility
JOH_SERVER_URL4. Joh.cgi – Auxiliary CGI Utility
johd3. Johd – Jabber Over HTTP Daemon
l, -l option introduced2.1 Configure johd Sockets
L, -L option, described2.6 Logging and Debugging
L, -L string3. Johd – Jabber Over HTTP Daemon
l, -l url3. Johd – Jabber Over HTTP Daemon
log tag2.6 Logging and Debugging
P, -P3. Johd – Jabber Over HTTP Daemon
p, -p file3. Johd – Jabber Over HTTP Daemon
P, -P option, described2.6 Logging and Debugging
p, -p option, described2.4 Two Ways to Start johd
PID2.4 Two Ways to Start johd
pidfile2.4 Two Ways to Start johd
pies2.4 Two Ways to Start johd
R, -R option, introduction2.5 HTTP GET Requests
R, -R url3. Johd – Jabber Over HTTP Daemon
S, -S name3. Johd – Jabber Over HTTP Daemon
S, -S option introduced2.1 Configure johd Sockets
s, -s url3. Johd – Jabber Over HTTP Daemon
service name, TCP wrappers2.1 Configure johd Sockets
severity level2.6 Logging and Debugging
signals3.3 Signals
socket class2.1 Configure johd Sockets
sockets, johd2.1 Configure johd Sockets
source location2.6 Logging and Debugging
standalone mode2.2 Using JOH in Standalone Mode
standalone mode, defined2. Quick Start
startup script2.4 Two Ways to Start johd
startup, johd2.4 Two Ways to Start johd
syslog2.6 Logging and Debugging
t, -t type:timeout3. Johd – Jabber Over HTTP Daemon
tag, logging2.6 Logging and Debugging
TCP wrappers2.1 Configure johd Sockets
u, -u option, introduction2.4 Two Ways to Start johd
u, -u user3. Johd – Jabber Over HTTP Daemon
UNIX socket3.1 URLs
unix, URL3.1 URLs
V, -V3. Johd – Jabber Over HTTP Daemon
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The decision which class to take as the default is somehow arbitrary, we might as well have chosen HTTP, but historically it happened to be CGI.


Again, the choice was somewhat arbitrary, but we know of no other service using this number.


See hosts_access(5), for detailed description of TCP wrapper access control files.

Note also, that this feature can be disabled at compile time, by the ‘--without-tcp-wrappers’ option to configure, although this is highly unrecommended.

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