Chat now with support
Chat with Support

syslog-ng Open Source Edition 3.16 - Administration Guide

Preface Introduction to syslog-ng The concepts of syslog-ng Installing syslog-ng The syslog-ng OSE quick-start guide The syslog-ng OSE configuration file source: Read, receive, and collect log messages
How sources work default-network-drivers: Receive and parse common syslog messages internal: Collecting internal messages file: Collecting messages from text files wildcard-file: Collecting messages from multiple text files network: Collecting messages using the RFC3164 protocol (network() driver) nodejs: Receiving JSON messages from nodejs applications mbox: Converting local e-mail messages to log messages osquery: Collect and parse osquery result logs pipe: Collecting messages from named pipes pacct: Collecting process accounting logs on Linux program: Receiving messages from external applications snmptrap: Read Net-SNMP traps sun-streams: Collecting messages on Sun Solaris syslog: Collecting messages using the IETF syslog protocol (syslog() driver) system: Collecting the system-specific log messages of a platform systemd-journal: Collecting messages from the systemd-journal system log storage systemd-syslog: Collecting systemd messages using a socket tcp, tcp6, udp, udp6: Collecting messages from remote hosts using the BSD syslog protocol— OBSOLETE unix-stream, unix-dgram: Collecting messages from UNIX domain sockets stdin: Collecting messages from the standard input stream
destination: Forward, send, and store log messages
amqp: Publishing messages using AMQP elasticsearch: Sending messages directly to Elasticsearch version 1.x elasticsearch2: Sending logs directly to Elasticsearch and Kibana 2.0 or higher file: Storing messages in plain-text files graphite: Sending metrics to Graphite Sending logs to Graylog hdfs: Storing messages on the Hadoop Distributed File System (HDFS) Posting messages over HTTP http: Posting messages over HTTP without Java kafka: Publishing messages to Apache Kafka loggly: Using Loggly logmatic: Using Logmatic.io mongodb: Storing messages in a MongoDB database network: Sending messages to a remote log server using the RFC3164 protocol (network() driver) osquery: Sending log messages to osquery's syslog table pipe: Sending messages to named pipes program: Sending messages to external applications pseudofile() redis: Storing name-value pairs in Redis riemann: Monitoring your data with Riemann smtp: Generating SMTP messages (e-mail) from logs Splunk: Sending log messages to Splunk sql: Storing messages in an SQL database stomp: Publishing messages using STOMP syslog: Sending messages to a remote logserver using the IETF-syslog protocol syslog-ng: Forwarding messages and tags to another syslog-ng node tcp, tcp6, udp, udp6: Sending messages to a remote log server using the legacy BSD-syslog protocol (tcp(), udp() drivers) Telegram: Sending messages to Telegram unix-stream, unix-dgram: Sending messages to UNIX domain sockets usertty: Sending messages to a user terminal: usertty() destination Write your own custom destination in Java or Python
log: Filter and route log messages using log paths, flags, and filters Global options of syslog-ng OSE TLS-encrypted message transfer template and rewrite: Format, modify, and manipulate log messages parser: Parse and segment structured messages db-parser: Process message content with a pattern database (patterndb) Correlating log messages Enriching log messages with external data Statistics of syslog-ng Multithreading and scaling in syslog-ng OSE Troubleshooting syslog-ng Best practices and examples The syslog-ng manual pages Third-party contributions Creative Commons Attribution Non-commercial No Derivatives (by-nc-nd) License About us

systemd-journal() source options

The systemd-journal() driver has the following options:

default-facility()
Type: facility string
Default: local0

Description: The default facility value if the SYSLOG_FACILITY entry does not exist.

default-level()
Type: string
Default: notice

Description: The default level value if the PRIORITY entry does not exist.

default-level()
Type: string
Default: notice

Description: The default level value if the PRIORITY entry does not exist.

hook-commands()

Description: This option makes it possible to execute external programs when the relevant driver is initialized or torn down. The hook-commands() can be used with all source and destination drivers with the exception of the usertty() and internal() drivers.

NOTE: The syslog-ng OSE application must be able to start and restart the external program, and have the necessary permissions to do so. For example, if your host is running AppArmor or SELinux, you might have to modify your AppArmor or SELinux configuration to enable syslog-ng OSE to execute external applications.

Using the hook-commands() when syslog-ng OSE starts or stops

To execute an external program when syslog-ng OSE starts or stops, use the following options:

startup()
Type: string
Default: N/A

Description: Defines the external program that is executed as syslog-ng OSE starts.

shutdown()
Type: string
Default: N/A

Description: Defines the external program that is executed as syslog-ng OSE stops.
Using the hook-commands() when syslog-ng OSE reloads

To execute an external program when the syslog-ng OSE configuration is initiated or torn down, for example, on startup/shutdown or during a syslog-ng OSE reload, use the following options:

setup()
Type: string
Default: N/A

Description: Defines an external program that is executed when the syslog-ng OSE configuration is initiated, for example, on startup or during a syslog-ng OSE reload.
teardown()
Type: string
Default: N/A

Description: Defines an external program that is executed when the syslog-ng OSE configuration is stopped or torn down, for example, on shutdown or during a syslog-ng OSE reload.
Example: Using the hook-commands() with a network source

In the following example, the hook-commands() is used with the network() driver and it opens an iptables port automatically as syslog-ng OSE is started/stopped.

The assumption in this example is that the LOGCHAIN chain is part of a larger ruleset that routes traffic to it. Whenever the syslog-ng OSE created rule is there, packets can flow, otherwise the port is closed.

source {
   network(transport(udp)
	hook-commands(
          startup("iptables -I LOGCHAIN 1 -p udp --dport 514 -j ACCEPT")
          shutdown("iptables -D LOGCHAIN 1")
        )
     );
};
host-override()
Type: string
Default:

Description: Replaces the ${HOST} part of the message with the parameter string.

keep-hostname()
Type: yes or no
Default: no

Description: Enable or disable hostname rewriting.

  • If enabled (keep-hostname(yes)), syslog-ng OSE will retain the hostname information read from the systemd journal messages.

  • If disabled (keep-hostname(no)), syslog-ng OSE will use the hostname that has been set up for the operating system instance that syslog-ng is running on. To query or set this value, use the hostnamectl command.

This option can be specified globally, and per-source as well. The local setting of the source overrides the global option if available.

max-field-size()
Type: number (characters)
Default: 65536

Description: The maximum length of a field's value.

prefix()
Type: string
Default: .journald.

Description: If this option is set, every non-built-in mapped names get a prefix (for example: ".SDATA.journald."). By default, syslog-ng OSE adds the .journald. prefix to every value.

read-old-records()
Type: yes|no
Default: yes

Description: If set to yes, syslog-ng OSE will start reading the records from the beginning of the journal, if the journal has not been read yet. If set to no, syslog-ng OSE will read only the new records. If the source has a state in the persist file, this option will have no effect.

time-zone()
Type: name of the timezone, or the timezone offset
Default:

Description: The default timezone for messages read from the source. Applies only if no timezone is specified within the message itself.

The timezone can be specified by using the name, for example, time-zone("Europe/Budapest")), or as the timezone offset in +/-HH:MM format, for example, +01:00). On Linux and UNIX platforms, the valid timezone names are listed under the /usr/share/zoneinfo directory.

use-fqdn()
Type: yes or no
Default: no

Description: Add Fully Qualified Domain Name instead of short hostname. This option can be specified globally, and per-source as well. The local setting of the source overrides the global option if available.

 NOTE:

This option has no effect if the keep-hostname() option is enabled (keep-hostname(yes)) and the message contains a hostname.

systemd-syslog: Collecting systemd messages using a socket

On platforms running systemd, the systemd-syslog() driver reads the log messages of systemd using the /run/systemd/journal/syslog socket. Note the following points about this driver:

  • If possible, use the more reliable systemd-journal() driver instead.

  • The socket activation of systemd is buggy, causing some log messages to get lost during system startup.

  • If syslog-ng OSE is running in a jail or a Linux Container (LXC), it will not read from the /dev/kmsg or /proc/kmsg files.

Declaration:
systemd-syslog();
Example: Using the systemd-syslog() driver
@version: 3.16

source s_systemdd {
    systemd-syslog();
};

destination d_network {
    syslog("server.host");
};

log {
    source(s_systemdd);
    destination(d_network);
};

systemd

The systemd-syslog() driver has the following options:

hook-commands()

Description: This option makes it possible to execute external programs when the relevant driver is initialized or torn down. The hook-commands() can be used with all source and destination drivers with the exception of the usertty() and internal() drivers.

NOTE: The syslog-ng OSE application must be able to start and restart the external program, and have the necessary permissions to do so. For example, if your host is running AppArmor or SELinux, you might have to modify your AppArmor or SELinux configuration to enable syslog-ng OSE to execute external applications.

Using the hook-commands() when syslog-ng OSE starts or stops

To execute an external program when syslog-ng OSE starts or stops, use the following options:

startup()
Type: string
Default: N/A

Description: Defines the external program that is executed as syslog-ng OSE starts.

shutdown()
Type: string
Default: N/A

Description: Defines the external program that is executed as syslog-ng OSE stops.
Using the hook-commands() when syslog-ng OSE reloads

To execute an external program when the syslog-ng OSE configuration is initiated or torn down, for example, on startup/shutdown or during a syslog-ng OSE reload, use the following options:

setup()
Type: string
Default: N/A

Description: Defines an external program that is executed when the syslog-ng OSE configuration is initiated, for example, on startup or during a syslog-ng OSE reload.
teardown()
Type: string
Default: N/A

Description: Defines an external program that is executed when the syslog-ng OSE configuration is stopped or torn down, for example, on shutdown or during a syslog-ng OSE reload.
Example: Using the hook-commands() with a network source

In the following example, the hook-commands() is used with the network() driver and it opens an iptables port automatically as syslog-ng OSE is started/stopped.

The assumption in this example is that the LOGCHAIN chain is part of a larger ruleset that routes traffic to it. Whenever the syslog-ng OSE created rule is there, packets can flow, otherwise the port is closed.

source {
   network(transport(udp)
	hook-commands(
          startup("iptables -I LOGCHAIN 1 -p udp --dport 514 -j ACCEPT")
          shutdown("iptables -D LOGCHAIN 1")
        )
     );
};

tcp, tcp6, udp, udp6: Collecting messages from remote hosts using the BSD syslog protocol— OBSOLETE

 NOTE:

The tcp(), tcp6(), udp(), and udp6() drivers are obsolete. Use the network() source and the network() destination instead. For details, see network: Collecting messages using the RFC3164 protocol (network() driver) and network: Sending messages to a remote log server using the RFC3164 protocol (network() driver), respectively.

The tcp(), tcp6(), udp(), udp6() drivers can receive syslog messages conforming to RFC3164 from the network using the TCP and UDP networking protocols. The tcp6() and udp6() drivers use the IPv6 network protocol, while tcp() and udp() use IPv4.

To convert your existing tcp(), tcp6(), udp(), udp6() source drivers to use the network() driver, see Change an old source driver to the network() driver.

Related Documents

The document was helpful.

Select Rating

I easily found the information I needed.

Select Rating