The container can have a different logging driver than the Docker daemon. Use the --log-driver=VALUE with the docker run command to configure the container's logging driver. The following options are supported:
none | Disables any logging for the container. docker logs won't be available with this driver. |
|---|---|
json-file | Default logging driver for Docker. Writes JSON messages to file. |
syslog | Syslog logging driver for Docker. Writes log messages to syslog. |
journald | Journald logging driver for Docker. Writes log messages to journald. |
gelf | Graylog Extended Log Format (GELF) logging driver for Docker. Writes log messages to a GELF endpoint likeGraylog or Logstash. |
fluentd | Fluentd logging driver for Docker. Writes log messages to fluentd (forward input). |
The docker logscommand is available only for the json-file logging driver.
The following logging options are supported for the json-file logging driver:
--log-opt max-size=[0-9+][k|m|g] --log-opt max-file=[0-9+]
Logs that reach max-size are rolled over. You can set the size in kilobytes(k), megabytes(m), or gigabytes(g). eg --log-opt max-size=50m. If max-size is not set, then logs are not rolled over.
max-file specifies the maximum number of files that a log is rolled over before being discarded. eg --log-opt max-file=100. If max-size is not set, then max-file is not honored.
If max-size and max-file are set, docker logs only returns the log lines from the newest log file.
The following logging options are supported for the syslog logging driver:
--log-opt syslog-address=[tcp|udp]://host:port --log-opt syslog-address=unix://path --log-opt syslog-facility=daemon --log-opt syslog-tag="mailer"
syslog-address specifies the remote syslog server address where the driver connects to. If not specified it defaults to the local unix socket of the running system. If transport is either tcp or udp and port is not specified it defaults to 514 The following example shows how to have the syslog driver connect to a syslog remote server at 192.168.0.42 on port 123
$ docker run --log-driver=syslog --log-opt syslog-address=tcp://192.168.0.42:123
The syslog-facility option configures the syslog facility. By default, the system uses the daemon value. To override this behavior, you can provide an integer of 0 to 23 or any of the following named facilities:
kernusermaildaemonauthsysloglprnewsuucpcronauthprivftplocal0local1local2local3local4local5local6local7The syslog-tag specifies a tag that identifies the container's syslog messages. By default, the system uses the first 12 characters of the container id. To override this behavior, specify a syslog-tag option
The journald logging driver stores the container id in the journal's CONTAINER_ID field. For detailed information on working with this logging driver, see the journald logging driver reference documentation.
The GELF logging driver supports the following options:
--log-opt gelf-address=udp://host:port --log-opt gelf-tag="database"
The gelf-address option specifies the remote GELF server address that the driver connects to. Currently, only udp is supported as the transport and you must specify a port value. The following example shows how to connect the gelf driver to a GELF remote server at 192.168.0.42 on port 12201
$ docker run --log-driver=gelf --log-opt gelf-address=udp://192.168.0.42:12201
The gelf-tag option specifies a tag for easy container identification.
You can use the --log-opt NAME=VALUE flag to specify these additional Fluentd logging driver options.
fluentd-address: specify host:port to connect [localhost:24224]fluentd-tag: specify tag for fluentd message,When specifying a fluentd-tag value, you can use the following markup tags:
{{.ID}}: short container id (12 characters){{.FullID}}: full container id{{.Name}}: container nameFor example, to specify both additional options:
docker run --log-driver=fluentd --log-opt fluentd-address=localhost:24224 --log-opt fluentd-tag=docker.{{.Name}}
If container cannot connect to the Fluentd daemon on the specified address, the container stops immediately. For detailed information on working with this logging driver, see the fluentd logging driver