Chat now with support
Chat mit Support

syslog-ng Premium Edition 7.0.18 - 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 linux-audit: Collecting messages from Linux audit logs network: Collecting messages using the RFC3164 protocol (network() driver) office365: Fetching logs from Office 365 osquery: Collect and parse osquery result logs pipe: Collecting messages from named pipes program: Receiving messages from external applications python: writing server-style Python sources python-fetcher: writing fetcher-style Python sources 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 udp-balancer: Receiving UDP messages at very high rate unix-stream, unix-dgram: Collecting messages from UNIX domain sockets windowsevent: Collecting Windows event logs
Sending and storing log messages — destinations and destination drivers
elasticsearch2: Sending messages directly to Elasticsearch version 2.0 or higher (DEPRECATED) elasticsearch-http: Sending messages to Elasticsearch HTTP Event Collector 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 python: writing custom Python destinations smtp: Generating SMTP messages (email) from logs splunk-hec: Sending messages to Splunk HTTP Event Collector sql: Storing messages in an SQL database stackdriver: Sending logs to the Google Stackdriver cloud syslog: Sending messages to a remote logserver using the IETF-syslog protocol syslog-ng(): Forward logs 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 Client-side failover
Routing messages: log paths, flags, and filters Global options of syslog-ng PE TLS-encrypted message transfer Advanced Log Transfer Protocol Reliability and minimizing the loss of log messages Manipulating messages parser: Parse and segment 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 Glossary

Client modes

The syslog-ng PE application can interact with Elasticsearch in the following modes of operation: node, and transport.

  • Transport mode

    The syslog-ng PE application uses the transport client API of Elasticsearch, and uses the server(), port(), and cluster() options from the syslog-ng PE configuration file.

  • Node mode

    The syslog-ng PE application acts as an Elasticsearch node (client no-data), using the node client API of Elasticsearch. Further options for the node can be describe in an Elasticsearch configuration file specified in the resource() option.

    NOTE:

    In Node mode, it is required to define the home of the elasticsearch installation with the path.home parameter in the .yml file. For example: path.home: /usr/share/elasticsearch.

Elasticsearch2 destination options (DEPRECATED)

Caution:

This destination is deprecated and will be removed from a future version of syslog-ng PE. We recommend using the elasticsearch-http: Sending messages to Elasticsearch HTTP Event Collector destination instead.

The elasticsearch2 destination can directly send log messages to Elasticsearch, allowing you to search and analyze your data in real time, and visualize it with Kibana. The elasticsearch2 destination has the following options.

Required options

The following options are required: index(), type(). In node mode, either the cluster() or the resource() option is required as well. Note that to use elasticsearch2, you must add the following lines to the beginning of your syslog-ng PE configuration:

@module mod-java
@include "scl.conf"
client-lib-dir()
Type: string
Default: The syslog-ng PE module directory: /opt/syslog-ng/lib/syslog-ng/java-modules/

Description: The list of the paths where the required Java classes are located. For example, class-path("/opt/syslog-ng/lib/syslog-ng/java-modules/:/opt/my-java-libraries/libs/"). If you set this option multiple times in your syslog-ng PE configuration (for example, because you have multiple Java-based destinations), syslog-ng PE will merge every available paths to a single list.

Description: Include the path to the directory where you copied the required libraries (see Prerequisites), for example, client_lib_dir(/user/share/elasticsearch-2.2.0/lib).

client-mode()
Type: transport | node
Default: node

Description: Specifies the client mode used to connect to the Elasticsearch server, for example, client-mode("node").

  • Transport mode

    The syslog-ng PE application uses the transport client API of Elasticsearch, and uses the server(), port(), and cluster() options from the syslog-ng PE configuration file.

  • Node mode

    The syslog-ng PE application acts as an Elasticsearch node (client no-data), using the node client API of Elasticsearch. Further options for the node can be describe in an Elasticsearch configuration file specified in the resource() option.

    NOTE:

    In Node mode, it is required to define the home of the elasticsearch installation with the path.home parameter in the .yml file. For example: path.home: /usr/share/elasticsearch.

cluster()
Type: string
Default: N/A

Description: Specifies the name or the Elasticsearch cluster, for example, cluster("my-elasticsearch-cluster"). Optionally, you can specify the name of the cluster in the Elasticsearch resource file. For details, see resource().

cluster-url()
Type: string
Default: N/A

Description: Specifies the URL or the Elasticsearch cluster, for example, cluster-url("http://192.168.10.10:9200")"). Note that this option works only in HTTP mode: client_mode(http)

concurrent-requests()
Type: number
Default: 0

Description: The number of concurrent (simultaneous) requests that syslog-ng PE sends to the Elasticsearch server. Set this option to 1 or higher to increase performance. When using the concurrent-requests() option, make sure that the flush-limit() option is higher than one, otherwise it will not have any noticeable effect. For details, see flush-limit().

Caution:

Hazard of data loss! Using the concurrent-requests() option increases the number of messages lost in case the Elasticsearch server becomes inaccessible.

custom-id()
Type: template or template function
Default: N/A

Description: Use this option to specify a custom ID for the records inserted into Elasticsearch. If this option is not set, the Elasticsearch server automatically generates and ID for the message. For example: custom_id(${UNIQID}) (Note that to use the ${UNIQID} macro, the use-uniqid() global option must be enabled. For details, see use-uniqid().)

disk-buffer()

Description: This option enables putting outgoing messages into the disk-buffer file of the destination to avoid message loss in case of a system failure on the destination side. It has the following options:

reliable()
Type: yes|no
Default: no

Description: If set to yes, syslog-ng PE cannot lose logs in case of reload/restart, unreachable destination or syslog-ng PE crash. This solution provides a slower, but reliable disk-buffer option. It is created and initialized at startup and gradually grows as new messages arrive. If set to no, the normal disk-buffer option will be used. This provides a faster, but less reliable disk-buffer option.

Caution:

Hazard of data loss! If you change the value of reliable() option when there are messages in the disk-buffer file, the messages stored in the disk-buffer file will be lost.

dir()
Type: string
Default: N/A

Description: Defines the folder where the disk-buffer files are stored.

Note that changing the value the dir() option will not move or copy existing files from the old directory to the new one.

Caution:

When creating a new dir() option for a disk-buffer file, or modifying an existing one, make sure you delete the persist file.

syslog-ng PE creates disk-buffer files based on the path recorded in the persist file. Therefore, if the persist file is not deleted after modifying the dir() option, then following a restart, syslog-ng PE will look for or create disk-buffer files in their old location. To ensure that syslog-ng PE uses the new dir() setting, the persist file must not contain any information about the destinations which the disk-buffer file in question belongs to.

disk-buf-size()
Type: number (bytes)
Default:

Description: This is a required option. The maximum size of the disk-buffer file in bytes. The minimum value is 1048576 bytes. If you set a smaller value, the minimum value will be used automatically. It replaces the old log-disk-fifo-size() option.
mem-buf-length()
Type: number (messages)
Default: 10000
Description: Use this option if the option reliable() is set to no. This option contains the number of messages stored in overflow queue. It replaces the old log-fifo-size() option. It inherits the value of the global log-fifo-size() option if provided. If it is not provided, the default value is 10000 messages. Note that this option will be ignored if the option reliable() is set to yes.
mem-buf-size()
Type: number (bytes)
Default: 163840000
Description: Use this option if the option reliable() is set to yes. This option contains the size of the messages in bytes that is used in the memory part of the disk-buffer file. It replaces the old log-fifo-size() option. It does not inherit the value of the global log-fifo-size() option, even if it is provided. Note that this option will be ignored if the option reliable() is set to no.
qout-size()
Type: number (messages)
Default: 64
Description: The number of messages stored in the output buffer of the destination. Note that if you change the value of this option and the disk-buffer file already exists, the change will take effect when the disk-buffer file becomes empty.

Options reliable() and disk-buf-size() are required options.

Example: Examples for using disk-buffer()

In the following case reliable disk-buffer() is used.

destination d_demo {
    network("127.0.0.1"
        port(3333)
        disk-buffer(
            mem-buf-size(10000)
            disk-buf-size(2000000)
            reliable(yes)
            dir("/tmp/disk-buffer")
        )
    );
};

In the following case normal disk-buffer() is used.

destination d_demo {
    network("127.0.0.1"
        port(3333)
        disk-buffer(
            mem-buf-length(10000)
            disk-buf-size(2000000)
            reliable(no)
            dir("/tmp/disk-buffer")
        )
    );
};
flush-limit()
Type: number
Default: 5000

Description: The number of messages that syslog-ng PE sends to the Elasticsearch server in a single batch.

  • If flush-limit is set to 1: syslog-ng PE sends the message reliably: it sends a message to Elasticsearch, then waits for a reply from Elasticsearch. In case of failure, syslog-ng PE repeats sending the message, as set in the retries() parameter. If sending the message fails for retries() times, syslog-ng PE drops the message.

    This method ensures reliable message transfer, but is slow (about 1000 messages/second).

  • If flush-limit is higher than 1: syslog-ng PE sends messages in a batch, and receives the response asynchronously. In case of a problem, syslog-ng PE cannot resend the messages.

    This method is relatively fast (depending on the size of flush-limit, about 8000 messages/second), but the transfer is not reliable. In transport mode, over 5000-30000 messages can be lost before syslog-ng PE recognizes the error. In node mode, about 1000 messages can be lost.

  • If concurrent-requests is higher than 1, syslog-ng PE can send multiple batches simultaneously, increasing performance (and also the number of messages that can be lost in case of an error). For details, see concurrent-requests().

frac-digits()
Type: number
Default: 0

Description: The syslog-ng application can store fractions of a second in the timestamps according to the ISO8601 format. The frac-digits() parameter specifies the number of digits stored. The digits storing the fractions are padded by zeros if the original timestamp of the message specifies only seconds. Fractions can always be stored for the time the message was received. Note that syslog-ng can add the fractions to non-ISO8601 timestamps as well.

http-auth-type()
Type: none | basic | clientcert
Default: none

Description: Determines how syslog-ng PE authenticates to the Elasticsearch server. Depending on the value of this option, you might have to set other options as well. Possible values:

This option is used only in HTTPS mode: client_mode("https"), and is available in syslog-ng PE version 7.0.3 and newer.

Example: HTTPS authentication examples

The following simple examples show the different authentication modes.

Simple password authentication:

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("basic")
        http-auth-type-basic-username("example-username")
        http-auth-type-basic-password("example-password")
    );
};

Certificate authentication:

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("clientcert")
        java-keystore-filepath("<path-to-your-java-keystore>.jks")
        java-keystore-password("password-to-your-keystore")
    );
};

Verify the certificate of the Elasticsearch server without authentication:

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("none")
        java-truststore-filepath("<path-to-your-java-keystore>.jks")
        java-truststore-password("password-to-your-keystore")
    );
};

Verify the certificate of the Elasticsearch server and perform certificate authentication (this is actually a mutual, certificate-based authentication between the syslog-ng PE client and the Elasticsearch server):

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("clientcert")
        java-keystore-filepath("<path-to-your-java-keystore>.jks")
        java-keystore-password("password-to-your-keystore")
        java-truststore-filepath("<path-to-your-java-keystore>.jks")
        java-truststore-password("password-to-your-keystore")
    );
};
http-auth-type-basic-password()
Type: string
Default: N/A

Description: The password to use for password-authentication on the Elasticsearch server. You must also set the http-auth-type-basic-username option.

This option is used only in HTTPS mode with basic authentication: client_mode("https") and http-auth-type("basic"), and is available in syslog-ng PE version 7.0.3 and newer.

Simple password authentication:

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("basic")
        http-auth-type-basic-username("example-username")
        http-auth-type-basic-password("example-password")
    );
};
http-auth-type-basic-username()
Type: string
Default: N/A

Description: The username to use for password-authentication on the Elasticsearch server. You must also set the http-auth-type-basic-password option.

This option is used only in HTTPS mode with basic authentication: client_mode("https") and http-auth-type("basic"), and is available in syslog-ng PE version 7.0.3 and newer.

Simple password authentication:

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("basic")
        http-auth-type-basic-username("example-username")
        http-auth-type-basic-password("example-password")
    );
};
index()
Type: string
Default: N/A

Description: Name of the Elasticsearch index to store the log messages. You can use macros and templates as well. For example, index("syslog-ng_${YEAR}.${MONTH}.${DAY}").

java-keystore-filepath()
Type: string
Default: N/A

Description: Path to the Java keystore file that stores the certificate that syslog-ng PE uses to authenticate on the Elasticsearch server. You must also set the java-keystore-password option.

To import a certificate into a Java keystore, use the appropriate tool of your Java implementation. For example, on Oracle Java, you can use the keytool utility:

keytool -import -alias ca -file <certificate-to-import> -keystore <keystore-to-import> -storepass <password-to-the-keystore>

This option is used only in HTTPS mode with basic authentication: client_mode("https") and http-auth-type("clientcert"), and is available in syslog-ng PE version 7.0.3 and newer.

Certificate authentication:

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("clientcert")
        java-keystore-filepath("<path-to-your-java-keystore>.jks")
        java-keystore-password("password-to-your-keystore")
    );
};

Verify the certificate of the Elasticsearch server and perform certificate authentication (this is actually a mutual, certificate-based authentication between the syslog-ng PE client and the Elasticsearch server):

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("clientcert")
        java-keystore-filepath("<path-to-your-java-keystore>.jks")
        java-keystore-password("password-to-your-keystore")
        java-truststore-filepath("<path-to-your-java-keystore>.jks")
        java-truststore-password("password-to-your-keystore")
    );
};
java-keystore-password()
Type: string
Default: N/A

Description: The password of the Java keystore file set in the java-keystore-filepath option.

To import a certificate into a Java keystore, use the appropriate tool of your Java implementation. For example, on Oracle Java, you can use the keytool utility:

keytool -import -alias ca -file <certificate-to-import> -keystore <keystore-to-import> -storepass <password-to-the-keystore>

This option is used only in HTTPS mode with basic authentication: client_mode("https") and http-auth-type("clientcert"), and is available in syslog-ng PE version 7.0.3 and newer.

Certificate authentication:

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("clientcert")
        java-keystore-filepath("<path-to-your-java-keystore>.jks")
        java-keystore-password("password-to-your-keystore")
    );
};

Verify the certificate of the Elasticsearch server and perform certificate authentication (this is actually a mutual, certificate-based authentication between the syslog-ng PE client and the Elasticsearch server):

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("clientcert")
        java-keystore-filepath("<path-to-your-java-keystore>.jks")
        java-keystore-password("password-to-your-keystore")
        java-truststore-filepath("<path-to-your-java-keystore>.jks")
        java-truststore-password("password-to-your-keystore")
    );
};
java-truststore-filepath()
Type: string
Default: N/A

Description: Path to the Java keystore file that stores the CA certificate that syslog-ng PE uses to verify the certificate of the Elasticsearch server. You must also set the java-truststore-password option.

If you do not set the java-truststore-filepath option, syslog-ng PE does accepts any certificate that the Elasticsearch server shows. In this case, the identity of the server is not verified, only the connection is encrypted.

To import a certificate into a Java keystore, use the appropriate tool of your Java implementation. For example, on Oracle Java, you can use the keytool utility:

keytool -import -alias ca -file <certificate-to-import> -keystore <keystore-to-import> -storepass <password-to-the-keystore>

This option is used only in HTTPS mode: client_mode("https"), and is available in syslog-ng PE version 7.0.3 and newer.

Verify the certificate of the Elasticsearch server without authentication:

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("none")
        java-truststore-filepath("<path-to-your-java-keystore>.jks")
        java-truststore-password("password-to-your-keystore")
    );
};

Verify the certificate of the Elasticsearch server and perform certificate authentication (this is actually a mutual, certificate-based authentication between the syslog-ng PE client and the Elasticsearch server):

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("clientcert")
        java-keystore-filepath("<path-to-your-java-keystore>.jks")
        java-keystore-password("password-to-your-keystore")
        java-truststore-filepath("<path-to-your-java-keystore>.jks")
        java-truststore-password("password-to-your-keystore")
    );
};
java-truststore-password()
Type: string
Default: N/A

Description: The password of the Java truststore file set in the java-truststore-filepath option.

To import a certificate into a Java keystore, use the appropriate tool of your Java implementation. For example, on Oracle Java, you can use the keytool utility:

keytool -import -alias ca -file <certificate-to-import> -keystore <keystore-to-import> -storepass <password-to-the-keystore>

This option is used only in HTTPS mode: client_mode("https"), and is available in syslog-ng PE version 7.0.3 and newer.

Verify the certificate of the Elasticsearch server without authentication:

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("none")
        java-truststore-filepath("<path-to-your-java-keystore>.jks")
        java-truststore-password("password-to-your-keystore")
    );
};

Verify the certificate of the Elasticsearch server and perform certificate authentication (this is actually a mutual, certificate-based authentication between the syslog-ng PE client and the Elasticsearch server):

destination d_elastic {
    elasticsearch2(
        client-mode("https")
        cluster("es-syslog-ng")
        index("x201")
        cluster-url("http://192.168.33.10:9200")
        type("slng_test_type")
        flush-limit("0")
        http-auth-type("clientcert")
        java-keystore-filepath("<path-to-your-java-keystore>.jks")
        java-keystore-password("password-to-your-keystore")
        java-truststore-filepath("<path-to-your-java-keystore>.jks")
        java-truststore-password("password-to-your-keystore")
    );
};
jvm-options()
Type: list
Default: N/A

Description: Specify the Java Virtual Machine (JVM) settings of your Java destination from the syslog-ng PE configuration file.

For example:

jvm-options("-Xss1M -XX:+TraceClassLoading")

You can set this option only as a global option, by adding it to the options statement of the syslog-ng configuration file.

log-fifo-size()
Type: number
Default: Use global setting.

Description: The number of messages that the output queue can store.

on-error()
Accepted values:

drop-message|drop-property|fallback-to-string|

silently-drop-message|silently-drop-property|silently-fallback-to-string

Default: Use the global setting (which defaults to drop-message)

Description: Controls what happens when type-casting fails and syslog-ng PE cannot convert some data to the specified type. By default, syslog-ng PE drops the entire message and logs the error. Currently the value-pairs() option uses the settings of on-error().

  • drop-message: Drop the entire message and log an error message to the internal() source. This is the default behavior of syslog-ng PE.

  • drop-property: Omit the affected property (macro, template, or message-field) from the log message and log an error message to the internal() source.

  • fallback-to-string: Convert the property to string and log an error message to the internal() source.

  • silently-drop-message: Drop the entire message silently, without logging the error.

  • silently-drop-property: Omit the affected property (macro, template, or message-field) silently, without logging the error.

  • silently-fallback-to-string: Convert the property to string silently, without logging the error.

port()
Type: number
Default: 9300

Description: The port number of the Elasticsearch server. This option is used only in transport mode: client-mode("transport")

retries()
Type: number (of attempts)
Default: 3

Description: The number of times syslog-ng PE attempts to send a message to this destination. If syslog-ng PE could not send a message, it will try again until the number of attempts reaches retries, then drops the message.

resource()
Type: string
Default: N/A

Description: The list of Elasticsearch resources to load, separated by semicolons. For example, resource("/home/user/elasticsearch/elasticsearch.yml;/home/user/elasticsearch/elasticsearch2.yml").

server()
Type: list of hostnames
Default: 127.0.0.1

Description: Specifies the hostname or IP address of the Elasticsearch server. When specifying an IP address, IPv4 (for example, 192.168.0.1) or IPv6 (for example, [::1]) can be used as well. When specifying multiple addresses, use space to separate the addresses, for example, server("127.0.0.1 remote-server-hostname1 remote-server-hostname2")

This option is used only in transport mode: client_mode("transport")

In version 7.0.3 and newer, you can list multiple servers in HTTP and HTTPS mode in the cluster_url() and server() options. The syslog-ng PE application will use these destination servers in load-balancing fashion. Note that load-balancing is handled by an external library (Jest), syslog-ng PE does not have any direct influence on it.

For example:

destination d_elasticsearch {
    elasticsearch2(
        client-lib-dir("/usr/share/elasticsearch/lib/")
        index("syslog-${YEAR}.${MONTH}.${DAY}")
        type("syslog")
        time-zone("UTC")
        client_mode("http")
        server("node01 node02")
        port(9200)
    );
};
skip-cluster-health-check()
Type: yes|no
Default: no

Description: By default, when connecting to an Elasticsearch cluster, syslog-ng PE checks the state of the cluster. If the primary shards of the cluster are not active, syslog-ng PE will not send messages, but wait for them to become active. To disable this health check and send the messages to Elasticsearch anyway, use the skip-cluster-health-check(yes) option in your configuration.

template()
Type: template or template function
Default: $(format-json --scope rfc5424 --exclude DATE --key ISODATE @timestamp=${ISODATE})

Description: The message as sent to the Elasticsearch server. Typically, you will want to use the command-line notation of the format-json template function.

To add a @timestamp field to the message, for example, to use with Kibana, include the @timestamp=${ISODATE} expression in the template. For example: template($(format-json --scope rfc5424 --exclude DATE --key ISODATE @timestamp=${ISODATE}))

For details on formatting messages in JSON format, see format-json.

throttle()
Type: number
Default: 0

Description: Sets the maximum number of messages sent to the destination per second. Use this output-rate-limiting functionality only when using the disk-buffer option as well to avoid the risk of losing messages. Specifying 0 or a lower value sets the output limit to unlimited.

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

Description: Convert timestamps to the timezone specified by this option. If this option is not set, then the original timezone information in the message is used. Converting the timezone changes the values of all date-related macros derived from the timestamp, for example, HOUR. For the complete list of such macros, see Date-related macros.

The timezone can be specified as using the name of the (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.

Version 7.0.3 and newer of syslog-ng PE automatically converts the timestamp (date) of the message to UTC, as needed by Elasticsearch and Kibana.

ts-format()
Type: rfc3164, bsd, rfc3339, iso
Default: rfc3164

Description: Override the global timestamp format (set in the global ts-format() parameter) for the specific destination. For details, see ts-format().

type()
Type: string
Default: N/A

Description: The type of the index. For example, type("test").

elasticsearch-http: Sending messages to Elasticsearch HTTP Event Collector

Version 7.0.14 of syslog-ng PE can directly post log messages to an Elasticsearch deployment using the Elasticsearch Bulk API over the HTTP and Secure HTTP (HTTPS) protocols.

HTTPS connection, as well as password- and certificate-based authentication is supported. The content of the events is sent in JSON format.

NOTE:

In order to use this destination, syslog-ng Premium Edition must run in server mode. Typically, only the central syslog-ng Premium Edition server uses this destination. For details on the server mode, see Server mode.

Declaration
d_elasticsearch_http {
    elasticsearch-http(
        index("<elasticsearch-index-to-store-messages>")
        url("https://your-elasticsearch-server1:9200/_bulk" "https://your-elasticsearch-server2:9200/_bulk")
        type("<type-of-the-index>")
    );
};
Example: Sending log data to Elasticsearch

The following example defines a elasticsearch-http() destination, with only the required options.

destination d_elasticsearch_http {
    elasticsearch-http(
        index("<name-of-the-index>")
        type("<type-of-the-index>")
        url("http://my-elastic-server:9200/_bulk")
    );
};


log {
    source(s_file);
    destination(d_elasticsearch_http);
    flags(flow-control);
};

The following example uses mutually-authenticated HTTPS connection, templated index, and also sets the type() and some other options.

destination d_elasticsearch_https {
    elasticsearch-http(
        url("https://node01.example.com:9200/_bulk")
        index("test-${YEAR}${MONTH}${DAY}")
        time-zone("UTC")
        type("test")
        workers(4)
        batch-lines(16)
        timeout(10)
        tls(
            ca-file("ca.pem")
            cert-file("syslog_ng.crt.pem")
            key-file("syslog_ng.key.pem")
            peer-verify(yes)
        )
    );
};

Batch mode and load balancing

The elasticsearch-http() destination automatically sends multiple log messages in a single HTTP request, increasing the rate of messages that your Elasticsearch deployment can consume. For details on adjusting and fine-tuning the batch mode of the elasticsearch-http() destination, see the following section.

Batch size

The batch-lines(), batch-lines(), and batch-timeout() options of the destination determine how many log messages syslog-ng PE sends in a batch. The batch-lines() option determines the maximum number of messages syslog-ng PE puts in a batch in. This can be limited based on size and time:

  • syslog-ng PE sends a batch every batch-timeout() milliseconds, even if the number of messages in the batch is less than batch-lines(). This ensures that the destination receives every message in a timely manner even if suddenly there are no more messages.

  • syslog-ng PE sends the batch if the total size of the messages in the batch reaches batch-bytes() bytes.

To increase the performance of the destination, increase the number of worker threads for the destination using the workers() option, or adjust the batch-bytes(), batch-lines(), batch-timeout() options.

Example: HTTP batch mode

In the following example, a batch consists of 100 messages, or a maximum of 512 kilobytes, and is sent every 20 seconds (20000 milliseconds).

destination d_elasticsearch-http {
    elasticsearch-http(url("http://your-elasticsearch-server:9200/_bulk")
        index("<elasticsearch-index-to-store-messages>")
        type("")
        url("http://your-elasticsearch-server:9200/_bulk")
        batch-lines(100)
        batch-bytes(512Kb)
        batch-timeout(10000)
    );
};
Load balancing between multiple Elasticsearch indexers

Starting with version 7.0.12, you can specify multiple URLs, for example, url("site1", "site2"). In this case, syslog-ng PE sends log messages to the specified URLs in a load-balance fashion. This means that syslog-ng PE sends each message to only one URL. For example, you can use this to send the messages to a set of ingestion nodes or indexers of your SIEM solution if a single node cannot handle the load. Note that the order of the messages as they arrive on the servers can differ from the order syslog-ng PE has received them, so use load-balancing only if your server can use the timestamp from the messages. If the server uses the timestamp when it receives the messages, the order of the messages will be incorrect.

Caution:

If you set multiple URLs in the url() option, set the persist-name() option as well to avoid data loss.

Example: HTTP load balancing

The following destination sends log messages to 3 different Elasticsearch indexer nodes. Each node is assigned a separate worker thread. A batch consists of 100 messages, or a maximum of 512 kilobytes, and is sent every 20 seconds (20000 milliseconds).

destination d_elasticsearch-http {
    elasticsearch-http(url("http://your-elasticsearch-server1:9200/_bulk" "http://your-elasticsearch-server2:9200/_bulk" "http://your-elasticsearch-server3:9200/_bulk")
        batch-lines(100)
        batch-bytes(512Kb)
        batch-timeout(20000)
        persist-name("d_elasticsearch-http-load-balance")
    );
};

If you are using load-balancing (that is, you have configured multiple servers in the url() option), increase the number of worker threads at least to the number of servers. For example, if you have set three URLs (url("site1", "site2", "site3")), set the workers() option to 3 or more.

Verwandte Dokumente