Based on the syslog4j library bundled with Graylog.
This plugin allows you to forward messages from a Graylog 2.X server in syslog format. Messages can be dispatched over TCP or UDP and formatted as plain text (classic), structured syslog (rfc 5424) or CEF (experimental).
This plugin supports Graylog 2.X+.
This plugin is also published on graylog marketplace.
https://marketplace.graylog.org/addons/8eb67dc0-b855-455c-a37f-0fa8ae522854
This project is using Maven and requires Java 8 or higher.
You can build a plugin (JAR) with mvn package
.
- Download graylog2-output-syslog-.jar from releases and put inside plugins folder
- Restart Graylog server
- Create a new output globally or attached to a stream.
- Message dispatch protocol: Select tcp or udp
- Syslog host: Hostname of the remote syslog serevr
- Syslog port: Syslog receiver port on remote host, usually 514
- Format: Specify one of plain, structured, full, cef or custom:FQCN (see below for explanation on values)
Standard plain syslog format. Minimal information. Example:
<14>Mar 31 19:19:02 nginx runit-service - GET /test1/x HTTP/1.1
Based on rfc5424. Sends all fields + log message. Example:
<14>1 2016-03-31T19:31:46.358Z graylog unknown - nginx [all@0 request_verb="GET" remote_addr="192.168.1.37" response_status="404" from_nginx="true" level="6" connection_requests="1" http_version="1.1" response_bytes="1906" source="nginx" message="GET /test1/2 HTTP/1.1" gl2_source_input="566c96abe4b094dfbc2661a8" version="1.1" nginx_access="true" http_user_agent="Wget/1.15 (linux-gnu)" remote_user="-" connection_id="1755" http_referer="-" request_path="/test1/2" gl2_source_node="bebd092c-85d7-49a3-8188-f7af734747fb" _id="34cb0f40-f777-11e5-b30c-0800276c97db" millis="0.002" facility="runit-service" timestamp="2016-03-31T19:31:46.000Z"] GET /test1/2 HTTP/1.1
Common event format aka HP ArcSight format. For this format to work you must set ARCSight port which expects CEF messages without syslog header. Also read CEF format handling below.
A variation of structured format except full message is added. Example:
<14>1 2016-03-31T19:19:02.524Z graylog unknown - nginx [all@0 request_verb="GET" remote_addr="192.168.1.37" response_status="404" from_nginx="true" level="6" connection_requests="1" http_version="1.1" response_bytes="1906" source="nginx" message="GET /test1/x HTTP/1.1" gl2_source_input="566c96abe4b094dfbc2661a8" version="1.1" nginx_access="true" http_user_agent="Wget/1.15 (linux-gnu)" remote_user="-" connection_id="970" http_referer="-" request_path="/test1/x" gl2_source_node="bebd092c-85d7-49a3-8188-f7af734747fb" _id="6d833da0-f775-11e5-b30c-0800276c97db" millis="0.002" facility="runit-service" timestamp="2016-03-31T19:19:02.000Z"] source: nginx | message: GET /test1/x HTTP/1.1 { request_verb: GET | remote_addr: 192.168.1.37 | response_status: 404 | from_nginx: true | level: 6 | connection_requests: 1 | http_version: 1.1 | response_bytes: 1906 | gl2_source_input: 566c96abe4b094dfbc2661a8 | version: 1.1 | nginx_access: true | http_user_agent: Wget/1.15 (linux-gnu) | remote_user: - | connection_id: 970 | http_referer: - | request_path: /test1/x | gl2_source_node: bebd092c-85d7-49a3-8188-f7af734747fb | _id: 6d833da0-f775-11e5-b30c-0800276c97db | millis: 0.002 | facility: runit-service | timestamp: 2016-03-31T19:19:02.000Z }
Specify your implementation of com.wizecore.graylog2.plugin.MessageSender interface.
Here is the algorithm for CEF message delivery used in this plugin. If you don`t understand that this, consult Common Event Format Guide
Plugin outputs CEF Header with following fields: CEF:0|Graylog|graylog-output-syslog:cefsender|2.3.1|
Currently it is hardcoded as log:1
- If message contains
act
field then it is used - If message contains
short_message
field then it is used - else Graylog messageId is used for Name field
New lines are stripped from this field. Proper escaping applied.
Mapping performed between syslog level and CEF log level.
Syslog | CEF |
---|---|
DEBUG | 1 |
NOTICE | 2 |
INFO | 3 |
WARN | 6 |
ERROR | 7 |
CRITICAL | 8 |
ALERT | 9 |
EMERGENCY | 10 |
Every existing message fields is written to Extension except message
, full_message
and short_message
If existing fields does not contain such keys, following fields will be added to extension:
CEF Key Name | Source |
---|---|
start | Message timestamp, unix time in milliseconds |
msg | Message text (message ) |
externalId | Message ID (assigned by Graylog) |
- https://tools.ietf.org/html/rfc5424
- https://github.com/Graylog2
- http://blog.rootshell.be/2011/05/11/ossec-speaks-arcsight/
- https://groups.google.com/forum/#!topic/ossec-list/3guXmHJYHtY
- http://habrahabr.ru/post/151631/
- http://www.syslog4j.org/
- https://www.graylog.org/resources/gelf-2/
- http://docs.graylog.org/en/1.0/pages/plugins.html
- https://community.saas.hpe.com/t5/ArcSight-Connectors/ArcSight-Common-Event-Format-CEF-Guide/ta-p/1589306