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spamd - Unix, Linux Command


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NAME

spamd - daemonized version of spamassassin

SYNOPSIS

spamd [options]

Options:


 -l, --allow-tell                  Allow learning/reporting
 -c, --create-prefs                Create user preferences files
 -C path, --configpath=path        Path for default config files
 --siteconfigpath=path             Path for site configs
 --cf=’config line’                Additional line of configuration
 -d, --daemonize                   Daemonize
 -h, --help                        Print usage message
 -i [ipaddr], --listen-ip=ipaddr   Listen on the IP ipaddr
 --ipv4only, --ipv4-only, --ipv4   Disable attempted use of ipv6 for DNS
 -p port, --port=port              Listen on specified port
 -m num, --max-children=num        Allow maximum num children
 --min-children=num                Allow minimum num children
 --min-spare=num                Lower limit for number of spare children
 --max-spare=num                Upper limit for number of spare children
 --max-conn-per-child=num          Maximum connections accepted by child
                                   before it is respawned
 --round-robin                     Use traditional prefork algorithm
 --timeout-tcp=secs                Connection timeout for client headers
 --timeout-child=secs              Connection timeout for message checks
 -q, --sql-config                  Enable SQL config (needs -x)
 -Q, --setuid-with-sql             Enable SQL config (needs -x,
                                   enables use of -H)
 --ldap-config                     Enable LDAP config (needs -x)
 --setuid-with-ldap                Enable LDAP config (needs -x,
                                   enables use of -H)
 --virtual-config-dir=dir          Enable pattern based Virtual configs
                                   (needs -x)
 -r pidfile, --pidfile             Write the process id to pidfile
 -s facility, --syslog=facility    Specify the syslog facility
 --syslog-socket=type              How to connect to syslogd
 -u username, --username=username  Run as username
 -g groupname, --groupname=groupname  Run as groupname
 -v, --vpopmail                    Enable vpopmail config
 -x, --nouser-config               Disable user config files
 --auth-ident                      Use ident to authenticate spamc user
 --ident-timeout=timeout           Timeout for ident connections
 -A host,..., --allowed-ips=..,..  Limit ip addresses which can connect
 -D, --debug[=areas]               Print debugging messages (for areas)
 -L, --local                       Use local tests only (no DNS)
 -P, --paranoid                    Die upon user errors
 -H [dir], --helper-home-dir[=dir]  Specify a different HOME directory
 --ssl                             Run an SSL server
 --ssl-port port                   Listen on port for SSL connections
 --ssl-version sslversion          Specify SSL protocol version to use
 --server-key keyfile              Specify an SSL keyfile
 --server-cert certfile            Specify an SSL certificate
 --socketpath=path                 Listen on given UNIX domain socket
 --socketowner=name                Set UNIX domain socket file’s owner
 --socketgroup=name                Set UNIX domain socket file’s group
 --socketmode=mode                 Set UNIX domain socket file’s mode
 -V, --version                     Print version and exit

DESCRIPTION

The purpose of this program is to provide a daemonized version of the spamassassin executable. The goal is improving throughput performance for automated mail checking.

This is intended to be used alongside spamc, a fast, low-overhead C client program.

See the README file in the spamd directory of the SpamAssassin distribution for more details.

Note: Although spamd will check per-user config files for every message, any changes to the system-wide config files will require either restarting spamd or forcing it to reload itself via SIGHUP for the changes to take effect.

Note: If spamd receives a SIGHUP, it internally reloads itself, which means that it will change its pid and might not restart at all if its environment changed (ie. if it can’t change back into its own directory). If you plan to use SIGHUP, you should always start spamd with the -r switch to know its current pid.

OPTIONS

Options of the long form can be shortened as long as they remain unambiguous. (i.e. --dae can be used instead of --daemonize) Also, boolean options (like --user-config) can be negated by adding no (--nouser-config), however, this is usually unnecessary.
TagDescription
-l, --allow-tell Allow learning and forgetting (to a local Bayes database), reporting and revoking (to a remote database) by spamd. The client issues a TELL command to tell what type of message is being processed and whether local (learn/forget) or remote (report/revoke) databases should be updated.

Note that spamd always trusts the username passed in (unless --auth-ident is used) so clients could maliciously learn messages for other users. (This is not ususally a concern with an SQL Bayes store as users will typically have read-write access directly to the database, and can also use sa-learn with the -u option to achieve the same result.)

-c, --create-prefs Create user preferences files if they don’t exist (default: don’t).
-C path, --configpath=path Use the specified path for locating the distributed configuration files. Ignore the default directories (usually /usr/share/spamassassin or similar).
--siteconfigpath=path Use the specified path for locating site-specific configuration files. Ignore the default directories (usually /etc/mail/spamassassin or similar).
--cf=’config line’ Add additional lines of configuration directly from the command-line, parsed after the configuration files are read. Multiple --cf arguments can be used, and each will be considered a separate line of configuration.
-d, --daemonize Detach from starting process and run in background (daemonize).
-h, --help Print a brief help message, then exit without further action.
-V, --version Print version information, then exit without further action.
-i [ipaddress], --listen-ip[=ipaddress], --ip-address[=ipaddress] Tells spamd to listen on the specified IP address (defaults to 127.0.0.1). If you specify no IP address after the switch, spamd will listen on all interfaces. (This is equal to the address 0.0.0.0). You can also use a valid hostname which will make spamd listen on the first address that name resolves to.
-p port, --port=port Optionally specifies the port number for the server to listen on (default: 783).

If the --ssl switch is used, and --ssl-port is not supplied, then this port will be used to accept SSL connections instead of unencrypted connections. If the --ssl switch is used, and --ssl-port is set, then unencrypted connections will be accepted on the --port at the same time as encrypted connections are accepted at --ssl-port.

-q, --sql-config Turn on SQL lookups even when per-user config files have been disabled with -x. this is useful for spamd hosts which don’t have user’s home directories but do want to load user preferences from an SQL database.

If your spamc client does not support sending the User: header, like exiscan, then the SQL username used will always be nobody.

This inhibits the setuid() behavior, so the -u option is required. If you want the setuid() behaviour, use -Q or --setuid-with-sql instead.

--ldap-config Turn on LDAP lookups. This is completely analog to --sql-config, only it is using an LDAP server.

Like --sql-config, this disables the setuid behavior, and requires -u. If you want it, use --setuid-with-ldap instead.

-Q, --setuid-with-sql Turn on SQL lookups even when per-user config files have been disabled with -x and also setuid to the user. This is useful for spamd hosts which want to load user preferences from an SQL database but also wish to support the use of -H (Helper home directories.)
--setuid-with-ldap Turn on LDAP lookups even when per-user config files have been disabled with -x and also setuid to the user. This is again completely analog to --setuid-with-sql, only it is using an LDAP server.
--virtual-config-dir=pattern This option specifies where per-user preferences can be found for virtual users, for the -x switch. The pattern is used as a base pattern for the directory name. Any of the following escapes can be used:
TagDescription
%u — replaced with the full name of the current user, as sent by spamc.
%l — replaced with the ’local part’ of the current username. In other words, if the username is an email address, this is the part before the @ sign.
%d — replaced with the ’domain’ of the current username. In other words, if the username is an email address, this is the part after the @ sign.
%% — replaced with a single percent sign (%).

So for example, if /vhome/users/%u/spamassassin is specified, and spamc sends a virtual username of jm@example.com, the directory /vhome/users/jm@example.com/spamassassin will be used.

The set of characters allowed in the virtual username for this path are restricted to:


        A-Z a-z 0-9 - + _ . , @ =

All others will be replaced by underscores (_).

This path must be a writable directory. It will be created if it does not already exist. If a file called user_prefs exists in this directory (note: not in a .spamassassin subdirectory!), it will be loaded as the user’s preferences. The Bayes databases for that user will be stored in this directory.

Note that this requires that -x is used, and cannot be combined with SQL- or LDAP-based configuration.

The pattern must expand to an absolute directory when spamd is running daemonized (-d).

Currently, use of this without -u is not supported. This inhibits setuid.

-r pidfile, --pidfile=pidfile Write the process ID of the spamd parent to the file specified by pidfile. The file will be unlinked when the parent exits. Note that when running with the -u option, the file must be writable by that user.
-v, --vpopmail Enable vpopmail config. If specified with with -u set to the vpopmail user, this allows spamd to lookup/create user_prefs in the vpopmail user’s own maildir. This option is useful for vpopmail virtual users who do not have an entry in the system /etc/passwd file.

Currently, use of this without -u is not supported. This inhibits setuid.

-s facility, --syslog=facility Specify the syslog facility to use (default: mail). If stderr is specified, output will be written to stderr. (This is useful if you’re running spamd under the daemontools package.) With a facility of file, all output goes to spamd.log. facility is interpreted as a file name to log to if it contains any characters except a-z and 0-9. null disables logging completely (used internally).

Examples:
        spamd -s mail # use syslog, facility mail (default)
        spamd -s ./mail # log to file ./mail
        spamd -s stderr 2>/dev/null # log to stderr, throw messages away
        spamd -s null # the same as above
        spamd -s file # log to file ./spamd.log
        spamd -s /var/log/spamd.log # log to file /var/log/spamd.log

If logging to a file is enabled and that log file is rotated, the spamd server must be restarted with a SIGHUP. (If the log file is just truncated, this is not needed but still recommended.)

Note that logging to a file does not use locking, so you cannot intermix logging from spamd and other processes into the same file. If you want to mix logging like this, use syslog instead.

If you use syslog logging, it is essential to send a SIGHUP to the spamd daemon when you restart the syslogd daemon. (This is due to a shortcoming in Perl’s syslog handling, where the disappearance of the connection to the syslogd is considered a fatal error.)

--syslog-socket=type Specify how spamd should send messages to syslogd. The options are unix, inet or none. The default is to try unix first, falling back to inet if perl detects errors in its unix support.

Some platforms, or versions of perl, are shipped with dysfunctional versions of the Sys::Syslog package which do not support some socket types, so you may need to set this. If you get error messages regarding __PATH_LOG or similar from spamd, try changing this setting.

The socket type file is used internally and should not be specified. Use the -s switch instead.

-u username, --username=username Run as the named user. If this option is not set, the default behaviour is to setuid() to the user running spamc, if spamd is running as root.

Note: --username=root is not a valid option. If specified, spamd will exit with a fatal error on startup.

-g groupname, --groupname=groupname Run as the named group if --username is being used. If this option is not set when --username is used then the primary group for the user given to --username is used.
-x, --nouser-config, --user-config Turn off (on) reading of per-user configuration files (user_prefs) from the user’s home directory. The default behaviour is to read per-user configuration from the user’s home directory (--user-config).

This option does not disable or otherwise influence the SQL, LDAP or Virtual Config Dir settings.

--auth-ident Verify the username provided by spamc using ident. This is only useful if connections are only allowed from trusted hosts (because an identd that lies is trivial to create) and if spamc REALLY SHOULD be running as the user it represents. Connections are terminated immediately if authentication fails. In this case, spamc will pass the mail through unchecked. Failure to connect to an ident server, and response timeouts are considered authentication failures. This requires that Net::Ident be installed.
--ident-timeout=timeout Wait at most timeout seconds for a response to ident queries. Authentication that takes long that timeout seconds will fail, and mail will not be processed. Setting this to 0.0 or less results in no timeout, which is STRONGLY discouraged. The default is 5 seconds.
-A host,..., --allowed-ips=host,... Specify a list of authorized hosts or networks which can connect to this spamd instance. Single IP addresses can be given, ranges of IP addresses in address/masklength CIDR format, or ranges of IP addresses by listing 3 or less octets with a trailing dot. Hostnames are not supported, only IP addresses. This option can be specified multiple times, or can take a list of addresses separated by commas. Examples:

-A 10.11.12.13 — only allow connections from 10.11.12.13.

-A 10.11.12.13,10.11.12.14 — only allow connections from 10.11.12.13 and 10.11.12.14.

-A 10.200.300.0/24 — allow connections from any machine in the range 10.200.300.*.

-A 10. — allow connections from any machine in the range 10.*.*.*.

By default, connections are only accepted from localhost [127.0.0.1].

-D [area,...], --debug [area,...] Produce debugging output. If no areas are listed, all debugging information is printed. Diagnostic output can also be enabled for each area individually; area is the area of the code to instrument. For example, to produce diagnostic output on bayes, learn, and dns, use:


        spamassassin -D bayes,learn,dns

Higher priority informational messages that are suitable for logging in normal circumstances are available with an area of info.

For more information about which areas (also known as channels) are available, please see the documentation at:


        C<http://wiki.apache.org/spamassassin/DebugChannels>
--ipv4only, --ipv4-only, --ipv4 Do not use IPv6 for DNS tests. Use if the existing tests for IPv6 availablity produce incorrect results or crashes.
-L, --local Perform only local tests on all mail. In other words, skip DNS and other network tests. Works the same as the -L flag to spamassassin(1).
-P, --paranoid Die on user errors (for the user passed from spamc) instead of falling back to user nobody and using the default configuration.
-m number , --max-children=number This option specifies the maximum number of children to spawn. Spamd will spawn that number of children, then sleep in the background until a child dies, wherein it will go and spawn a new child.

Incoming connections can still occur if all of the children are busy, however those connections will be queued waiting for a free child. The minimum value is 1, the default value is 5.

Please note that there is a OS specific maximum of connections that can be queued (Try perl -MSocket -e’print SOMAXCONN’ to find this maximum).

Note that if you run too many servers for the amount of free RAM available, you run the danger of hurting performance by causing a high swap load as server processes are swapped in and out continually.

--min-children=number The minimum number of children that will be kept running. The minimum value is 1, the default value is 1. If you have lots of free RAM, you may want to increase this.
--min-spare=number The lower limit for the number of spare children allowed to run. A spare, or idle, child is one that is not handling a scan request. If there are too few spare children available, a new server will be started every second or so. The default value is 1.
--max-spare=number The upper limit for the number of spare children allowed to run. If there are too many spare children, one will be killed every second or so until the number of idle children is in the desired range. The default value is 2.
--max-conn-per-child=number This option specifies the maximum number of connections each child should process before dying and letting the master spamd process spawn a new child. The minimum value is 1, the default value is 200.
--round-robin By default, spamd will attempt to keep a small number of hot child processes as busy as possible, and keep any others as idle as possible, using something similar to the Apache httpd server scaling algorithm. This is accomplished by the master process coordinating the activities of the children. This switch will disable this scaling algorithm, and the behaviour seen in the 3.0.x versions will be used instead, where all processes receive an equal load and no scaling takes place.
--timeout-tcp=number This option specifies the number of seconds to wait for headers from a client (spamc) before closing the connection. The minimum value is 1, the default value is 30, and a value of 0 will disable socket timeouts completely.
--timeout-child=number This option specifies the number of seconds to wait for a spamd child to to process or check a message. The minimum value is 1, the default value is 300, and a value of 0 will disable child timeouts completely.
-H directory, --helper-home-dir=directory Specify that external programs such as Razor, DCC, and Pyzor should have a HOME environment variable set to a specific directory. The default is to use the HOME environment variable setting from the shell running spamd. By specifying no argument, spamd will use the spamc caller’s home directory instead.
--ssl Accept only SSL connections on the associated port. The IO::Socket::SSL perl module must be installed.

If the --ssl switch is used, and --ssl-port is not supplied, then --port port will be used to accept SSL connections instead of unencrypted connections. If the --ssl switch is used, and --ssl-port is set, then unencrypted connections will be accepted on the --port, at the same time as encrypted connections are accepted at --ssl-port.

--ssl-port=port Optionally specifies the port number for the server to listen on for SSL connections (default: whatever --port uses). See --ssl for more details.
--ssl-version=sslversion Specify the SSL protocol version to use, one of sslv2, sslv3, tlsv1, or sslv23. The default, sslv23, is the most flexible, accepting a SSLv2 or higher hello handshake, then negotiating use of SSLv3 or TLSv1 protocol if the client can accept it. Specifying --ssl-version implies --ssl.
--server-key keyfile Specify the SSL key file to use for SSL connections.
--server-cert certfile Specify the SSL certificate file to use for SSL connections.
--socketpath pathname Listen on UNIX domain path pathname instead of a TCP socket.

Warning: the Perl support on BSD platforms for UNIX domain sockets seems to have a bug regarding paths of over 100 bytes or so (SpamAssassin bug 4380). If you see a ’could not find newly-created UNIX socket’ error message, and the path appears truncated, this may be the cause. Try using a shorter path to the socket.

By default, use of --socketpath will inhibit SSL connections and unencrypted TCP connections. To enable them, specify --port and/or --ssl-port explicitly.

--socketowner name Set UNIX domain socket to be owned by the user named name. Note that this requires that spamd be started as root, and if -u is used, that user should have write permissions to unlink the file later, for when the spamd server is killed.
--socketgroup name Set UNIX domain socket to be owned by the group named name. See --socketowner for notes on ownership and permissions.
--socketmode mode Set UNIX domain socket to use the octal mode mode. Note that if -u is used, that user should have write permissions to unlink the file later, for when the spamd server is killed.

SEE ALSO

spamc(1) spamassassin(1) Mail::SpamAssassin::Conf(3) Mail::SpamAssassin(3)

PREREQUISITES

Mail::SpamAssassin

AUTHORS

The SpamAssassin(tm) Project (http://spamassassin.apache.org/)

LICENSE

SpamAssassin is distributed under the Apache License, Version 2.0, as described in the file LICENSE included with the distribution.

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