Chat now with support
Chat with Support

syslog-ng Premium Edition 7.0.9 - Administration Guide

Preface Introduction to syslog-ng The concepts of syslog-ng Installing syslog-ng The syslog-ng PE quick-start guide The syslog-ng PE configuration file Collecting log messages — sources and source drivers
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) osquery: Collect and parse osquery result logs pipe: Collecting messages from named pipes 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 unix-stream, unix-dgram: Collecting messages from UNIX domain sockets windowsevent: Collecting Windows event logs
Sending and storing log messages — destinations and destination drivers
elasticsearch: Sending messages directly to Elasticsearch version 1.x elasticsearch2: Sending messages directly to Elasticsearch version 2.0 or higher file: Storing messages in plain-text files hdfs: Storing messages on the Hadoop Distributed File System (HDFS) http: Posting messages over HTTP kafka: Publishing messages to Apache Kafka logstore: Storing messages in encrypted files mongodb: Storing messages in a MongoDB database network: Sending messages to a remote log server using the RFC3164 protocol (network() driver) pipe: Sending messages to named pipes program: Sending messages to external applications smtp: Generating SMTP messages (e-mail) from logs Splunk: Sending log messages to Splunk sql: Storing messages in an SQL database 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) unix-stream, unix-dgram: Sending messages to UNIX domain sockets usertty: Sending messages to a user terminal — usertty() destination
Routing messages: log paths, flags, and filters Global options of syslog-ng PE TLS-encrypted message transfer Reliable Log Transfer Protocol Manipulating messages Parsers and segmenting structured messages Processing message content with a pattern database Correlating log messages Enriching log messages with external data Monitoring statistics and metrics of syslog-ng Multithreading and scaling in syslog-ng PE Troubleshooting syslog-ng Best practices and examples The syslog-ng manual pages About us

Prerequisites to installing syslog-ng PE

  • The binary installer packages of syslog-ng Premium Edition include every required dependency for most platforms, only the ncurses library is required as an external dependency (syslog-ng PE itself does not use the ncurses library, it is required only during the installation).


    There are two versions of every binary release. The one with the compact suffix does not include SQL support. If you are installing syslog-ng PE in client or relay mode, or you do not use the sql() source or destination, use the compact binaries. That way no unnecessary components are installed to your system.

  • For Java-based destinations (for example, Elasticsearch, Apache Kafka, HDFS), Java must be installed on the host where you use such destinations. Typically, this is the host where you are running syslog-ng PE in server mode.

  • DO NOT install syslog-ng PE on an NFS-mounted partition

  • DO NOT store the runtime files (for example, the configuration or the persist file) of syslog-ng PE on an NFS-mounted partition

Security-enhanced Linux: grsecurity, SELinux

Security-enhanced Linux solutions such as grsecurity or SELinux; can interfere with the operation of syslog-ng PE. The syslog-ng PE application supports these security enhancements as follows:

  • grsecurity: Version syslog-ng PE 5 F2 and later can be run on hosts using grsecurity, with the following limitations: using the Oracle SQL source and destination is not supported.

  • SELinux: Version syslog-ng PE 5 F2 and later properly supports SELinux on Red Hat Enterprise Linux 6.5 and newer platforms. The CentOS platforms corresponding to the supported RHEL versions are supported as well. For details, see Using syslog-ng PE on SELinux.

Installing syslog-ng using the .run installer


If you already had syslog-ng Open Source Edition (OSE) installed on the host, and are upgrading to syslog-ng Premium Edition, make sure that the ${SYSLOGNG_OPTIONS} environmental variable does not contain a -p <path-to-pid-file> option. If it does, remove this option from the environmental variable, because it can prevent syslog-ng PE from stopping properly. Typically, the environmental variable is set in the files /etc/default/syslog-ng or /etc/sysconfig/syslog-ng, depending on the operating system you use.

This section describes how to install the syslog-ng PE application interactively using the binary installer. The installer has a simple interface: use the TAB or the arrow keys of your keyboard to navigate between the options, and Enter to select an option.


The installer stops the running syslogd application if it is running, but its components are not removed. The /etc/init.d/sysklogd init script is automatically renamed to /etc/init.d/sysklogd.backup. Rename this file to its original name if you want to remove syslog-ng or restart the syslogd package.

Installing syslog-ng PE in client or relay mode


Complete the following steps to install syslog-ng Premium Edition on clients or relays. For details on the different operation modes of syslog-ng PE, see Modes of operation.



The native logrotation tools do not send a SIGHUP to syslog-ng after rotating the log files, causing syslog-ng to write into files already rotated. To solve this problem, the syslog-ng init script links the /var/run/ file to syslog-ng's pid. Also, on Linux, the script symlinks the initscript of the original syslog daemon to syslog-ng's initscript.

  1. Login to the Support Portal and download the syslog-ng PE installer package.

  2. Enable the executable attribute for the installer using the chmod +x syslog-ng-<edition>-<version>-<OS>-<platform>.run, then start the installer as root using the ./syslog-ng-<edition>-<version>-<OS>-<platform>.run command. (Note that the exact name of the file depends on the operating system and platform.) Wait until the package is uncompressed and the welcome screen appears, then select Continue.

    Figure 5: The welcome screen

  3. Accepting the EULA: You can install syslog-ng PE only if you understand and accept the terms of the End-User License Agreement (EULA). The full text of the EULA can be displayed during installation by selecting the Show EULA option, and is also available in this guide for convenience at Software Transaction, License and End User License Agreements. Select Accept to accept the EULA and continue the installation.

    If you do not accept the terms of the EULA for some reason, select Reject to cancel installing syslog-ng PE.

  4. Detecting platform and operating system: The installer attempts to automatically detect your oprating system and platform. If the displayed information is correct, select Yes. Otherwise select Exit to abort the installation, and verify that your platform is supported. For a list of supported platforms, see Supported platforms. If your platform is supported but not detected correctly, contact your local distributor, reseller, or access the Support Portal. For contact details, see About us.

    Figure 6: Platform detection

  5. Installation path: Enter the path to install syslog-ng PE to. This is useful if you intend to install syslog-ng PE without registering it as a service, or if it cannot be installed to the default location because of policy compliance reasons. If no path is given, syslog-ng PE is installed to the default folder.

    Figure 7: Installation path


    When installing syslog-ng PE to an alternative path on AIX, HP-UX, or Solaris platforms, set the CHARSETALIASDIR environmental variable to the lib subdirectory of the installation path. That way syslog-ng PE can find the charset.alias file.

  6. Registering as syslog service: Select Register to register syslog-ng PE as the syslog service. This will stop and disable the default syslog service of the system.

    Figure 8: Registering as syslog service

  7. Locating the license: Since you are installing syslog-ng PE in client or relay mode, simply select OK. For details on the different operation modes of syslog-ng PE, see Modes of operation.

  8. Upgrading: The syslog-ng PE installer can automatically detect if you have previously installed a version of syslog-ng PE on your system. To use the configuration file of this previous installation, select Yes. To ignore the old configuration file and create a new one, select No.

    Note that if you decide to use your existing configuration file, the installer automatically checks it for syntax error and displays a list of warnings and errors if it finds any problems.

    Figure 9: Upgrading syslog-ng

  9. Generating a new configuration file: The installer displays some questions to generate a new configuration file.

    1. Remote sources: Select Yes to accept log messages from the network. TCP, UDP, and SYSLOG messages on every interface will be automatically accepted.

      Figure 10: Accepting remote messages

    2. Remote destinations: Enter the IP address or hostname of your log server or relay and select OK.

      Figure 11: Forwarding messages to the log server


    Accepting remote messages and forwarding them to a log server means that syslog-ng PE will start in relay mode.

  10. After the installation is finished, add the /opt/syslog-ng/bin and /opt/syslog-ng/sbin directories to your search PATH environment variable. That way you can use syslog-ng PE and its related tools without having to specify the full pathname. Add the following line to your shell profile:

  11. (Optional step for SELinux-enabled systems): Complete Using syslog-ng PE on SELinux.

Related Documents

The document was helpful.

Select Rating

I easily found the information I needed.

Select Rating