The **config.toml** file is a configuration file for the containerd daemon. The

file must be placed in **/etc/containerd/** or used with the **--config**

option of **containerd** to be used by the daemon. If the file does not exist

at the appropriate location or is not provided via the **--config** option

containerd uses its default configuration settings, which can be displayed

with the **containerd config(1)** command.

The TOML file used to configure the containerd daemon settings has a short

list of global settings followed by a series of sections for specific areas

of daemon configuration. There is also a section for **plugins** that allows

each containerd plugin to have an area for plugin-specific configuration and

settings.

**root**

: The root directory for containerd metadata. (Default: "/var/lib/containerd")

**state**

: The state directory for containerd (Default: "/run/containerd")

**oom_score**

: The out of memory (OOM) score applied to the containerd daemon process (Default: 0)

**[grpc]**

: Section for gRPC socket listener settings. Contains three properties:

- **address** (Default: "/run/containerd/containerd.sock")

- **uid** (Default: 0)

- **gid** (Default: 0)

**[debug]**

: Section to enable and configure a debug socket listener. Contains four properties:

- **address** (Default: "/run/containerd/debug.sock")

- **uid** (Default: 0)

- **gid** (Default: 0)

- **level** (Default: "info") sets the debug log level

**[metrics]**

: Section to enable and configure a metrics listener. Contains two properties:

- **address** (Default: "") Metrics endpoint does not listen by default

- **grpc_histogram** (Default: false) Turn on or off gRPC histogram metrics

**[cgroup]**

: Section for Linux cgroup specific settings

- **path** (Default: "") Specify a custom cgroup path for created containers

**[plugins]**

: The plugins section contains configuration options exposed from installed plugins.

The following plugins are enabled by default and their settings are shown below.

Plugins that are not enabled by default will provide their own configuration values

documentation.

- **[plugins.cgroup]** has one option __no_prometheus__ (Default: **false**)

- **[plugins.diff]** has one option __default__, a list by default set to **["walking"]**

- **[plugins.linux]** has several options for configuring the runtime, shim, and related options:

**shim** specifies the shim binary (Default: **"containerd-shim"**),

**runtime** is the OCI compliant runtime binary (Default: **"runc"**),

**runtime_root** is the root directory used by the runtime (Default: **""**),

**no_shim** specifies whether to use a shim or not (Default: **false**),

**shim_debug** turns on debugging for the shim (Default: **false**)

- **[plugins.scheduler]** has several options that perform advanced tuning for the scheduler:

**pause_threshold** is the maximum amount of time GC should be scheduled (Default: **0.02**),

**deletion_threshold** guarantees GC is scheduled after n number of deletions (Default: **0** [not triggered]),

**mutation_threshold** guarantees GC is scheduled after n number of database mutations (Default: **100**),

**schedule_delay** defines the delay after trigger event before scheduling a GC (Default **"0ms"** [immediate]),

**startup_delay** defines the delay after startup before scheduling a GC (Default **"100ms"**)

The following is a complete **config.toml** default configuration example:

Please file any specific issues that you encounter at

https://github.com/containerd/containerd.

Phil Estes <estesp@gmail.com>

ctr(1), containerd-config(1), containerd(1)

containerd config [command]

The *containerd config* command has one subcommand, named *default*, which

will display on standard output the default containerd config for this version

of the containerd daemon.

This output can be piped to a __config.toml(5)__ file and placed in

**/etc/containerd** to be used as the configuration for containerd on daemon

startup. The configuration can be placed in any filesystem location and used

with the **--config** option to the containerd daemon as well.

See __config.toml(5)__ for more information on the containerd configuration

options.

**default**

: This subcommand will output the TOML formatted containerd configuration to standard output

Please file any specific issues that you encounter at

https://github.com/containerd/containerd.

Phil Estes <estesp@gmail.com>

ctr(1), config.toml(5), containerd(1)

containerd [global options] command [command options] [arguments...]

**containerd** is a high performance container runtime whose daemon can be started

by using this command. If none of the *config*, *publish*, or *help* commands

are specified the default action of the **containerd** command is to start the

containerd daemon in the foreground.

A default configuration is used if no TOML configuration is specified or located

at the default file location. The *containerd config* command can be used to

generate the default configuration for containerd. The output of that command

can be used and modified as necessary as a custom configuration.

The *publish* command is used internally by parts of the containerd runtime

to publish events. It is not meant to be used as a standalone utility.

**--config value, -c value**

: Specify the default path to the configuration file (default: "/etc/containerd/config.toml")

**--log-level value, -l value**

: Set the logging level. Available levels are: [debug, info, warn, error, fatal, panic]

**--address value, -a value**

: UNIX socket address for containerd's GRPC server to listen on (default: "/run/containerd/containerd.sock")

**--root value**

: The containerd root directory (default: "/var/lib/containerd"). A persistent directory location where metadata and image content are stored

**--state value**

: The containerd state directory (default: "/run/containerd"). A transient state directory used during containerd operation

**--help, -h**

: Show containerd command help text

**--version, -v**

: Print the containerd server version

Please file any specific issues that you encounter at

https://github.com/containerd/containerd.

Phil Estes <estesp@gmail.com>

ctr(1), config.toml(5), containerd-config(1)

**ctr [global options] command [command options] [arguments...]**

**ctr** is an unsupported debug and administrative client for interacting

with the containerd daemon. Because it is unsupported, the commands,

options, and operation are not guaranteed to be backward compatible or

stable from release to release of the containerd project.

The following commands are available in the **ctr** utility:

**plugins,plugin**

: Provides information about containerd plugins

**version**

: Prints the client and server versions

**containers,c,container**

: Manages and interacts with containers

**content**

: Manages and interacts with content

**events,event**

: Displays containerd events

**images,image**

: Manages and interacts with images

**namespaces,namespace**

: Manages and interacts with containerd namespaces

**pprof**

: Provides golang pprof outputs for containerd

**run**

: Runs a container

**snapshots,snapshot**

: Manages and interacts with snapshots

**tasks,t,task**

: Manages and interacts with tasks

**shim**

: Interacts with a containerd shim directly

**help,h**

: Displays a list of commands or help for one specific command

The following global options apply to all **ctr** commands:

**--debug**

: Enable debug output in logs

**--address value, -a value**

: Address for containerd's GRPC server (default: */run/containerd/containerd.sock*)

**--timeout value**

: Total timeout for ctr commands (default: *0s*)

**--connect-timeout value**

: Timeout for connecting to containerd (default: *0s*)

**--namespace value, -n value**

: Namespace to use with commands (default: *default*) [also read from *$CONTAINERD_NAMESPACE*]

**--help, -h**

: Show help text

**--version, -v**

: Prints the **ctr** version

Note that the **ctr** utility is not an officially supported part of the

containerd project releases.

However, please feel free to file any specific issues that you encounter at

https://github.com/containerd/containerd.

Phil Estes <estesp@gmail.com>

containerd(1), config.toml(5), containerd-config(1)

go get -u github.com/cpuguy83/go-md2man