docs/engine/admin/logging/overview.md

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---
description: Configure logging driver.
keywords: docker, logging, driver
redirect_from:
- /engine/reference/logging/overview/
- /engine/reference/logging/
- /engine/admin/reference/logging/
title: Configure logging drivers
---
Docker includes multiple logging mechanisms to help you
[get information from running containers and services](/engine/admin/logging/view_container_logs.md).
These mechanisms are called logging drivers.
Each Docker daemon has a default logging driver, which each container uses
unless you configure it to use a different logging driver.
In addition to using the logging drivers included with Docker, you can also
implement and use [logging driver plugins](/engine/admin/logging/plugins.md).
Logging driver plugins are available in Docker 17.05 and higher.
## Configure the default logging driver
To configure the Docker daemon to default to a specific logging driver, set the
value of `log-driver` to the name of the logging driver in the `daemon.json`
file, which is located in `/etc/docker/` on Linux hosts or
`C:\ProgramData\docker\config\` on Windows server hosts. The default logging
driver is `json-file`. The following example explicitly sets the default
logging driver to `syslog`:
```json
{
"log-driver": "syslog"
}
```
If the logging driver has configurable options, you can set them in the
`daemon.json` file as a JSON array with the key `log-opts`. The following
example sets two configurable options on the `json-file` logging driver:
```json
{
"log-driver": "json-file",
"log-opts": {
"labels": "production_status",
"env": "os,customer"
}
}
```
If you do not specify a logging driver, the default is `json-file`. Thus,
the default output for commands such as `docker inspect <CONTAINER>` is JSON.
To find the current default logging driver for the Docker daemon, run
`docker info` and search for `Logging Driver`. You can use the following
command on Linux, macOS, or PowerShell on Windows:
```bash
$ docker info |grep 'Logging Driver'
Logging Driver: json-file
```
## Configure the logging driver for a container
When you start a container, you can configure it to use a different logging
driver than the Docker daemon's default, using the `--log-driver` flag. If the
logging driver has configurable options, you can set them using one or more
instances of the `--log-opt <NAME>=<VALUE>` flag. Even if the container uses the
default logging driver, it can use different configurable options.
The following example starts an Alpine container with the `none` logging driver.
```bash
$ docker run -it --log-driver none alpine ash
```
To find the current logging driver for a running container, if the daemon
is using the `json-file` logging driver, run the following `docker inspect`
command, substituting the container name or ID for `<CONTAINER>`:
```bash
{% raw %}
$ docker inspect -f '{{.HostConfig.LogConfig.Type}}' <CONTAINER>
json-file
{% endraw %}
```
### Use environment variables or labels with logging drivers
Some logging drivers add the value of a container's `--env|-e` or `--label`
flags to the container's logs. This example starts a container using the Docker
daemon's default logging driver (let's assume `json-file`) but sets the
environment variable `os=ubuntu`.
```bash
$ docker run -dit --label production_status=testing -e os=ubuntu alpine sh
```
If the logging driver supports it, this adds additional fields to the logging
output. The following output is generated by the `json-file` logging driver:
```json
"attrs":{"production_status":"testing","os":"ubuntu"}
```
## Supported logging drivers
The following logging drivers are supported. See the link to each driver's
documentation for its configurable options, if applicable. If you are using
[logging driver plugins](/engine/admin/logging/plugins.md), you may
see more options.
| Driver | Description |
|:----------------------------|:--------------------------------------------------------------------------------------------------------------|
| `none` | No logs will be available for the container and `docker logs` will not return any output. |
| [`json-file`](json-file.md) | The logs are formatted as JSON. The default logging driver for Docker. |
| [`syslog`](syslog.md) | Writes logging messages to the `syslog` facility. The `syslog` daemon must be running on the host machine. |
| [`journald`](journald.md) | Writes log messages to `journald`. The `journald` daemon must be running on the host machine. |
| [`gelf`](gelf.md) | Writes log messages to a Graylog Extended Log Format (GELF) endpoint such as Graylog or Logstash. |
| [`fluentd`](fluentd.md) | Writes log messages to `fluentd` (forward input). The `fluentd` daemon must be running on the host machine. | |
| [`awslogs`](awslogs.md) | Writes log messages to Amazon CloudWatch Logs. |
| [`splunk`](splunk.md) | Writes log messages to `splunk` using the HTTP Event Collector. |
| [`etwlogs`](etwlogs.md) | Writes log messages as Event Tracing for Windows (ETW) events. Only available on Windows platforms. |
| [`gcplogs`](gcplogs.md) | Writes log messages to Google Cloud Platform (GCP) Logging. |
## Limitations of logging drivers
The `docker logs` command is not available for drivers other than `json-file`
and `journald`.