Task definition parameters - Amazon Elastic Container Service
FamilyTask roleTask execution roleNetwork modeContainer DefinitionsVolumesTask placement constraintsLaunch typesTask sizeProxy configurationOther task definition parameters

Task definition parameters

Task definitions are split into separate parts: the task family, the IAM task role, the network mode, container definitions, volumes, task placement constraints, and launch types. The family and container definitions are required in a task definition, while task role, network mode, volumes, task placement constraints, and launch type are optional.

The following are more detailed descriptions for each task definition parameter.

Family

family

Type: string

Required: yes

When you register a task definition, you give it a family, which is similar to a name for multiple versions of the task definition, specified with a revision number. The first task definition that is registered into a particular family is given a revision of 1, and any task definitions registered after that are given a sequential revision number.

Task role

taskRoleArn

Type: string

Required: no

When you register a task definition, you can provide a task role for an IAM role that allows the containers in the task permission to call the AWS APIs that are specified in its associated policies on your behalf. For more information, see IAM Roles for Tasks.

IAM roles for tasks on Windows require that the -EnableTaskIAMRole option is set when you launch the Amazon ECS-optimized Windows Server AMI. Your containers must also run some configuration code in order to take advantage of the feature. For more information, see Windows IAM roles for tasks.

Task execution role

executionRoleArn

Type: string

Required: no

The Amazon Resource Name (ARN) of the task execution role that grants the Amazon ECS container agent permission to make AWS API calls on your behalf. The task execution IAM role is required depending on the requirements of your task. For more information, see Amazon ECS task execution IAM role.

Network mode

networkMode

Type: string

Required: no

The Docker networking mode to use for the containers in the task. The valid values are none, bridge, awsvpc, and host. The default Docker network mode is bridge.

If the network mode is set to none, the task's containers do not have external connectivity and port mappings can't be specified in the container definition.

If the network mode is bridge, the task utilizes Docker's built-in virtual network which runs inside each container instance.

If the network mode is host, the task bypasses Docker's built-in virtual network and maps container ports directly to the EC2 instance's network interface directly. In this mode, you can't run multiple instantiations of the same task on a single container instance when port mappings are used.

If the network mode is awsvpc, the task is allocated an elastic network interface, and you must specify a NetworkConfiguration when you create a service or run a task with the task definition. For more information, see Task Networking with the awsvpc Network Mode. Currently, only the Amazon ECS-optimized AMI, other Amazon Linux variants with the ecs-init package, or AWS Fargate infrastructure support the awsvpc network mode.

The host and awsvpc network modes offer the highest networking performance for containers because they use the Amazon EC2 network stack instead of the virtualized network stack provided by the bridge mode. With the host and awsvpc network modes, exposed container ports are mapped directly to the corresponding host port (for the host network mode) or the attached elastic network interface port (for the awsvpc network mode), so you cannot take advantage of dynamic host port mappings.

Docker for Windows uses a different network mode (known as NAT) than Docker for Linux. When you register a task definition with Windows containers, you must not specify a network mode. If you use the AWS Management Console to register a task definition with Windows containers, you must choose the default network mode.

If using the Fargate launch type, the awsvpc network mode is required. If using the EC2 launch type, the allowable network mode depends on the underlying EC2 instance's operating system. If Linux, any network mode can be used. If Windows, only the NAT mode is allowed, as described above.

Container Definitions

When you register a task definition, you must specify a list of container definitions that are passed to the Docker daemon on a container instance. The following parameters are allowed in a container definition.

Standard Container Definition Parameters

The following task definition parameters are either required or used in most container definitions.

Name

name

Type: string

Required: yes

The name of a container. Up to 255 letters (uppercase and lowercase), numbers, hyphens, and underscores are allowed. If you are linking multiple containers together in a task definition, the name of one container can be entered in the links of another container to connect the containers.

Image

image

Type: string

Required: yes

The image used to start a container. This string is passed directly to the Docker daemon. Images in the Docker Hub registry are available by default. You can also specify other repositories with either repository-url/image:tag or repository-url/image@digest. Up to 255 letters (uppercase and lowercase), numbers, hyphens, underscores, colons, periods, forward slashes, and number signs are allowed. This parameter maps to Image in the Create a container section of the Docker Remote API and the IMAGE parameter of docker run.

  • When a new task starts, the Amazon ECS container agent pulls the latest version of the specified image and tag for the container to use. However, subsequent updates to a repository image are not propagated to already running tasks.

  • Images in private registries are supported. For more information, see Private registry authentication for tasks.

  • Images in Amazon ECR repositories can be specified by using either the full registry/repository:tag or registry/repository@digest naming convention. For example, aws_account_id.dkr.ecr.region.amazonaws.com/my-web-app:latest or aws_account_id.dkr.ecr.region.amazonaws.com/my-web-app@sha256:94afd1f2e64d908bc90dbca0035a5b567EXAMPLE

  • Images in official repositories on Docker Hub use a single name (for example, ubuntu or mongo).

  • Images in other repositories on Docker Hub are qualified with an organization name (for example, amazon/amazon-ecs-agent).

  • Images in other online repositories are qualified further by a domain name (for example, quay.io/assemblyline/ubuntu).

Memory

memory

Type: integer

Required: no

The amount (in MiB) of memory to present to the container. If your container attempts to exceed the memory specified here, the container is killed. The total amount of memory reserved for all containers within a task must be lower than the task memory value, if one is specified. This parameter maps to Memory in the Create a container section of the Docker Remote API and the --memory option to docker run.

If using the Fargate launch type, this parameter is optional.

If using the EC2 launch type, you must specify either a task-level memory value or a container-level memory value. If you specify both a container-level memory and memoryReservation value, memory must be greater than memoryReservation. If you specify memoryReservation, then that value is subtracted from the available memory resources for the container instance on which the container is placed. Otherwise, the value of memory is used.

The Docker daemon reserves a minimum of 4 MiB of memory for a container, so you should not specify fewer than 4 MiB of memory for your containers.

Note

If you are trying to maximize your resource utilization by providing your tasks as much memory as possible for a particular instance type, see Container Instance Memory Management.

memoryReservation

Type: integer

Required: no

The soft limit (in MiB) of memory to reserve for the container. When system memory is under contention, Docker attempts to keep the container memory to this soft limit; however, your container can consume more memory when needed, up to either the hard limit specified with the memory parameter (if applicable), or all of the available memory on the container instance, whichever comes first. This parameter maps to MemoryReservation in the Create a container section of the Docker Remote API and the --memory-reservation option to docker run.

If a task-level memory value is not specified, you must specify a non-zero integer for one or both of memory or memoryReservation in a container definition. If you specify both, memory must be greater than memoryReservation. If you specify memoryReservation, then that value is subtracted from the available memory resources for the container instance on which the container is placed. Otherwise, the value of memory is used.

For example, if your container normally uses 128 MiB of memory, but occasionally bursts to 256 MiB of memory for short periods of time, you can set a memoryReservation of 128 MiB, and a memory hard limit of 300 MiB. This configuration would allow the container to only reserve 128 MiB of memory from the remaining resources on the container instance, but also allow the container to consume more memory resources when needed.

The Docker daemon reserves a minimum of 4 MiB of memory for a container, so you should not specify fewer than 4 MiB of memory for your containers.

Port Mappings

portMappings

Type: object array

Required: no

Port mappings allow containers to access ports on the host container instance to send or receive traffic.

For task definitions that use the awsvpc network mode, you should only specify the containerPort. The hostPort can be left blank or it must be the same value as the containerPort.

Port mappings on Windows use the NetNAT gateway address rather than localhost. There is no loopback for port mappings on Windows, so you cannot access a container's mapped port from the host itself.

This parameter maps to PortBindings in the Create a container section of the Docker Remote API and the --publish option to docker run. If the network mode of a task definition is set to host, then host ports must either be undefined or they must match the container port in the port mapping.

Note

After a task reaches the RUNNING status, manual and automatic host and container port assignments are visible in the following locations:

  • Console: The Network Bindings section of a container description for a selected task.

  • AWS CLI: The networkBindings section of the describe-tasks command output.

  • API: The DescribeTasks response.

containerPort

Type: integer

Required: yes, when portMappings are used

The port number on the container that is bound to the user-specified or automatically assigned host port.

If using containers in a task with the Fargate launch type, exposed ports should be specified using containerPort.

If using containers in a task with the EC2 launch type and you specify a container port and not a host port, your container automatically receives a host port in the ephemeral port range. For more information, see hostPort. Port mappings that are automatically assigned in this way do not count toward the 100 reserved ports limit of a container instance.

hostPort

Type: integer

Required: no

The port number on the container instance to reserve for your container.

If using containers in a task with the Fargate launch type, the hostPort can either be left blank or be the same value as containerPort.

If using containers in a task with the EC2 launch type, you can specify a non-reserved host port for your container port mapping (this is referred to as static host port mapping), or you can omit the hostPort (or set it to 0) while specifying a containerPort and your container automatically receives a port (this is referred to as dynamic host port mapping) in the ephemeral port range for your container instance operating system and Docker version.

The default ephemeral port range Docker version 1.6.0 and later is listed on the instance under /proc/sys/net/ipv4/ip_local_port_range. If this kernel parameter is unavailable, the default empheral port range from 49153–65535 is used. Do not attempt to specify a host port in the ephemeral port range, as these are reserved for automatic assignment. In general, ports below 32768 are outside of the ephemeral port range.

The default reserved ports are 22 for SSH, the Docker ports 2375 and 2376, and the Amazon ECS container agent ports 51678-51680. Any host port that was previously user-specified for a running task is also reserved while the task is running (after a task stops, the host port is released). The current reserved ports are displayed in the remainingResources of describe-container-instances output, and a container instance may have up to 100 reserved ports at a time, including the default reserved ports. Automatically assigned ports do not count toward the 100 reserved ports limit.

protocol

Type: string

Required: no

The protocol used for the port mapping. Valid values are tcp and udp. The default is tcp.

Important

UDP support is only available on container instances that were launched with version 1.2.0 of the Amazon ECS container agent (such as the amzn-ami-2015.03.c-amazon-ecs-optimized AMI) or later, or with container agents that have been updated to version 1.3.0 or later. To update your container agent to the latest version, see Updating the Amazon ECS Container Agent.

If you are specifying a host port, use the following syntax:

"portMappings": [
    {
        "containerPort": integer,
        "hostPort": integer
    }
    ...
]

If you want an automatically assigned host port, use the following syntax: 

"portMappings": [
    {
        "containerPort": integer
    }
    ...
]

Advanced Container Definition Parameters

The following advanced container definition parameters provide extended capabilities to the docker run command that is used to launch containers on your Amazon ECS container instances.

Health Check

healthCheck

The container health check command and associated configuration parameters for the container. This parameter maps to HealthCheck in the Create a container section of the Docker Remote API and the HEALTHCHECK parameter of docker run.

Note

The Amazon ECS container agent only monitors and reports on the health checks specified in the task definition. Amazon ECS does not monitor Docker health checks that are embedded in a container image and not specified in the container definition. Health check parameters that are specified in a container definition override any Docker health checks that exist in the container image.

You can view the health status of both individual containers and a task with the DescribeTasks API operation or when viewing the task details in the console.

The following describes the possible healthStatus values for a container:

  • HEALTHY—The container health check has passed successfully.

  • UNHEALTHY—The container health check has failed.

  • UNKNOWN—The container health check is being evaluated or there is no container health check defined.

The following describes the possible healthStatus values for a task. The container health check status of nonessential containers do not have an effect on the health status of a task.

  • HEALTHY—All essential containers within the task have passed their health checks.

  • UNHEALTHY—One or more essential containers have failed their health check.

  • UNKNOWN—The essential containers within the task are still having their health checks evaluated or there are no container health checks defined.

If a task is run manually, and not as part of a service, the task will continue its lifecycle regardless of its health status. For tasks that are part of a service, if the task reports as unhealthy then the task will be stopped and the service scheduler will replace it.

The following are notes about container health check support:

  • Container health checks require version 1.17.0 or greater of the Amazon ECS container agent. For more information, see Updating the Amazon ECS Container Agent.

  • Container health checks are supported for Fargate tasks if you are using platform version 1.1.0 or later. For more information, see AWS Fargate platform versions.

  • Container health checks are not supported for tasks that are part of a service that is configured to use a Classic Load Balancer.

command

A string array representing the command that the container runs to determine if it is healthy. The string array can start with CMD to execute the command arguments directly, or CMD-SHELL to run the command with the container's default shell. If neither is specified, CMD is used by default.

When registering a task definition in the AWS Management Console, use a comma separated list of commands which will automatically converted to a string after the task definition is created. An example input for a health check could be: 

CMD-SHELL, curl -f http://localhost/ || exit 1

When registering a task definition using the AWS Management Console JSON panel, the AWS CLI, or the APIs, you should enclose the list of commands in brackets. An example input for a health check could be: 

[ "CMD-SHELL", "curl -f http://localhost/ || exit 1" ]

An exit code of 0 indicates success, and a non-zero exit code indicates failure. For more information, see HealthCheck in the Create a container section of the Docker Remote API.

interval

The time period in seconds between each health check execution. You may specify between 5 and 300 seconds. The default value is 30 seconds.

timeout

The time period in seconds to wait for a health check to succeed before it is considered a failure. You may specify between 2 and 60 seconds. The default value is 5 seconds.

retries

The number of times to retry a failed health check before the container is considered unhealthy. You may specify between 1 and 10 retries. The default value is three retries.

startPeriod

The optional grace period within which to provide containers time to bootstrap before failed health checks count towards the maximum number of retries. You may specify between 0 and 300 seconds. The startPeriod is disabled by default.

Environment

cpu

Type: integer

Required: no

The number of cpu units the Amazon ECS container agent will reserve for the container. This parameter maps to CpuShares in the Create a container section of the Docker Remote API and the --cpu-shares option to docker run.

This field is optional for tasks using the Fargate launch type, and the only requirement is that the total amount of CPU reserved for all containers within a task be lower than the task-level cpu value.

Note

You can determine the number of CPU units that are available per Amazon EC2 instance type by multiplying the number of vCPUs listed for that instance type on the Amazon EC2 Instances detail page by 1,024.

Linux containers share unallocated CPU units with other containers on the container instance with the same ratio as their allocated amount. For example, if you run a single-container task on a single-core instance type with 512 CPU units specified for that container, and that is the only task running on the container instance, that container could use the full 1,024 CPU unit share at any given time. However, if you launched another copy of the same task on that container instance, each task would be guaranteed a minimum of 512 CPU units when needed, and each container could float to higher CPU usage if the other container was not using it, but if both tasks were 100% active all of the time, they would be limited to 512 CPU units.

On Linux container instances, the Docker daemon on the container instance uses the CPU value to calculate the relative CPU share ratios for running containers. For more information, see CPU share constraint in the Docker documentation. The minimum valid CPU share value that the Linux kernel allows is 2. However, the CPU parameter is not required, and you can use CPU values below 2 in your container definitions. For CPU values below 2 (including null), the behavior varies based on your Amazon ECS container agent version:

  • Agent versions <= 1.1.0: Null and zero CPU values are passed to Docker as 0, which Docker then converts to 1,024 CPU shares. CPU values of 1 are passed to Docker as 1, which the Linux kernel converts to two CPU shares.

  • Agent versions >= 1.2.0: Null, zero, and CPU values of 1 are passed to Docker as two CPU shares.

On Windows container instances, the CPU limit is enforced as an absolute limit, or a quota. Windows containers only have access to the specified amount of CPU that is defined in the task definition. A null or zero CPU value is passed to Docker as 0, which Windows interprets as 1% of one CPU.

gpu

Type: ResourceRequirement object

Required: no

The number of physical GPUs the Amazon ECS container agent will reserve for the container. The number of GPUs reserved for all containers in a task should not exceed the number of available GPUs on the container instance the task is launched on. For more information, see Working with GPUs on Amazon ECS.

Note

This parameter is not supported for Windows containers or tasks using the Fargate launch type.

essential

Type: Boolean

Required: no

If the essential parameter of a container is marked as true, and that container fails or stops for any reason, all other containers that are part of the task are stopped. If the essential parameter of a container is marked as false, then its failure does not affect the rest of the containers in a task. If this parameter is omitted, a container is assumed to be essential.

All tasks must have at least one essential container. If you have an application that is composed of multiple containers, you should group containers that are used for a common purpose into components, and separate the different components into multiple task definitions. For more information, see Application architecture. 

"essential": true|false
entryPoint
Important

Early versions of the Amazon ECS container agent do not properly handle entryPoint parameters. If you have problems using entryPoint, update your container agent or enter your commands and arguments as command array items instead.

Type: string array

Required: no

The entry point that is passed to the container. This parameter maps to Entrypoint in the Create a container section of the Docker Remote API and the --entrypoint option to docker run. For more information about the Docker ENTRYPOINT parameter, go to https://docs.docker.com/engine/reference/builder/#entrypoint. 

"entryPoint": ["string", ...]
command

Type: string array

Required: no

The command that is passed to the container. This parameter maps to Cmd in the Create a container section of the Docker Remote API and the COMMAND parameter to docker run. For more information about the Docker CMD parameter, go to https://docs.docker.com/engine/reference/builder/#cmd. If there are multiple arguments, each argument should be a separated string in the array. 

"command": ["string", ...]
workingDirectory

Type: string

Required: no

The working directory in which to run commands inside the container. This parameter maps to WorkingDir in the Create a container section of the Docker Remote API and the --workdir option to docker run. 

"workingDirectory": "string"
environmentFiles

Type: object array

Required: no

A list of files containing the environment variables to pass to a container. This parameter maps to the --env-file option to docker run.

You can specify up to ten environment files. The file must have a .env file extension. Each line in an environment file should contain an environment variable in VARIABLE=VALUE format. Lines beginning with # are treated as comments and are ignored. For more information on the environment variable file syntax, see Declare default environment variables in file.

If there are individual environment variables specified in the container definition, they take precedence over the variables contained within an environment file. If multiple environment files are specified that contain the same variable, they are processed from the top down. It is recommended to use unique variable names. For more information, see Specifying environment variables.

This field is not valid for containers in tasks using the Fargate launch type.

value

Type: String

Required: Yes

The Amazon Resource Name (ARN) of the Amazon S3 object containing the environment variable file.

type

Type: String

Required: Yes

The file type to use. The only supported value is s3.

environment

Type: object array

Required: no

The environment variables to pass to a container. This parameter maps to Env in the Create a container section of the Docker Remote API and the --env option to docker run.

Important

We do not recommend using plaintext environment variables for sensitive information, such as credential data.

name

Type: String

Required: Yes, when environment is used

The name of the environment variable.

value

Type: String

Required: Yes, when environment is used

The value of the environment variable.

"environment" : [
    { "name" : "string", "value" : "string" },
    { "name" : "string", "value" : "string" }
]
secrets

Type: Object array

Required: No

An object representing the secret to expose to your container. For more information, see Specifying sensitive data.

name

Type: String

Required: Yes

The value to set as the environment variable on the container.

valueFrom

Type: String

Required: Yes

The secret to expose to the container. The supported values are either the full ARN of the AWS Secrets Manager secret or the full ARN of the parameter in the AWS Systems Manager Parameter Store.

Note

If the Systems Manager Parameter Store parameter exists in the same Region as the task you are launching then you can use either the full ARN or name of the secret. If the parameter exists in a different Region then the full ARN must be specified. 

"secrets": [
    {
        "name": "environment_variable_name",
        "valueFrom": "arn:aws:ssm:region:aws_account_id:parameter/parameter_name"
    }
]

Network Settings

disableNetworking

Type: Boolean

Required: no

When this parameter is true, networking is disabled within the container. This parameter maps to NetworkDisabled in the Create a container section of the Docker Remote API.

Note

This parameter is not supported for Windows containers or tasks using the awsvpc network mode. 

"disableNetworking": true|false
links

Type: string array

Required: no

The link parameter allows containers to communicate with each other without the need for port mappings. Only supported if the network mode of a task definition is set to bridge. The name:internalName construct is analogous to name:alias in Docker links. Up to 255 letters (uppercase and lowercase), numbers, hyphens, and underscores are allowed. For more information about linking Docker containers, go to https://docs.docker.com/engine/userguide/networking/default_network/dockerlinks/. This parameter maps to Links in the Create a container section of the Docker Remote API and the --link option to docker run.

Note

This parameter is not supported for Windows containers or tasks using the awsvpc network mode.

Important

Containers that are collocated on the same container instance may be able to communicate with each other without requiring links or host port mappings. The network isolation on a container instance is controlled by security groups and VPC settings. 

"links": ["name:internalName", ...]
hostname

Type: string

Required: no

The hostname to use for your container. This parameter maps to Hostname in the Create a container section of the Docker Remote API and the --hostname option to docker run.

Note

The hostname parameter is not supported if you are using the awsvpc network mode. 

"hostname": "string"
dnsServers

Type: string array

Required: no

A list of DNS servers that are presented to the container. This parameter maps to Dns in the Create a container section of the Docker Remote API and the --dns option to docker run.

Note

This parameter is not supported for Windows containers or tasks using the awsvpc network mode. 

"dnsServers": ["string", ...]
dnsSearchDomains

Type: string array

Required: no

Pattern: ^[a-zA-Z0-9-.]{0,253}[a-zA-Z0-9]$

A list of DNS search domains that are presented to the container. This parameter maps to DnsSearch in the Create a container section of the Docker Remote API and the --dns-search option to docker run.

Note

This parameter is not supported for Windows containers or tasks using the awsvpc network mode. 

"dnsSearchDomains": ["string", ...]
extraHosts

Type: object array

Required: no

A list of hostnames and IP address mappings to append to the /etc/hosts file on the container.

This parameter maps to ExtraHosts in the Create a container section of the Docker Remote API and the --add-host option to docker run.

Note

This parameter is not supported for Windows containers or tasks that use the awsvpc network mode. 

"extraHosts": [
      {
        "hostname": "string",
        "ipAddress": "string"
      }
      ...
    ]
hostname

Type: string

Required: yes, when extraHosts are used

The hostname to use in the /etc/hosts entry.

ipAddress

Type: string

Required: yes, when extraHosts are used

The IP address to use in the /etc/hosts entry.

Storage and Logging

readonlyRootFilesystem

Type: Boolean

Required: no

When this parameter is true, the container is given read-only access to its root file system. This parameter maps to ReadonlyRootfs in the Create a container section of the Docker Remote API and the --read-only option to docker run.

Note

This parameter is not supported for Windows containers.

"readonlyRootFilesystem": true|false
mountPoints

Type: Object Array

Required: No

The mount points for data volumes in your container.

This parameter maps to Volumes in the Create a container section of the Docker Remote API and the --volume option to docker run.

Windows containers can mount whole directories on the same drive as $env:ProgramData. Windows containers cannot mount directories on a different drive, and mount point cannot be across drives.

sourceVolume

Type: String

Required: Yes, when mountPoints are used

The name of the volume to mount.

containerPath

Type: String

Required: Yes, when mountPoints are used

The path on the container to mount the volume at.

readOnly

Type: Boolean

Required: No

If this value is true, the container has read-only access to the volume. If this value is false, then the container can write to the volume. The default value is false.

volumesFrom

Type: Object Array

Required: No

Data volumes to mount from another container. This parameter maps to VolumesFrom in the Create a container section of the Docker Remote API and the --volumes-from option to docker run.

sourceContainer

Type: string

Required: yes, when volumesFrom is used

The name of the container to mount volumes from.

readOnly

Type: Boolean

Required: no

If this value is true, the container has read-only access to the volume. If this value is false, then the container can write to the volume. The default value is false. 

"volumesFrom": [
                {
                  "sourceContainer": "string",
                  "readOnly": true|false
                }
              ]
logConfiguration

Type: LogConfiguration Object

Required: no

The log configuration specification for the container.

For example task definitions using a log configuration, see Example task definitions.

This parameter maps to LogConfig in the Create a container section of the Docker Remote API and the --log-driver option to docker run. By default, containers use the same logging driver that the Docker daemon uses; however the container may use a different logging driver than the Docker daemon by specifying a log driver with this parameter in the container definition. To use a different logging driver for a container, the log system must be configured properly on the container instance (or on a different log server for remote logging options). For more information on the options for different supported log drivers, see Configure logging drivers in the Docker documentation.

The following should be noted when specifying a log configuration for your containers:

  • Amazon ECS currently supports a subset of the logging drivers available to the Docker daemon (shown in the valid values below). Additional log drivers may be available in future releases of the Amazon ECS container agent.

  • This parameter requires version 1.18 of the Docker Remote API or greater on your container instance.

  • For tasks using the EC2 launch type, the Amazon ECS container agent running on a container instance must register the logging drivers available on that instance with the ECS_AVAILABLE_LOGGING_DRIVERS environment variable before containers placed on that instance can use these log configuration options. For more information, see Amazon ECS Container Agent Configuration.

  • For tasks using the Fargate launch type, because you do not have access to the underlying infrastructure your tasks are hosted on, any additional software needed will have to be installed outside of the task. For example, the Fluentd output aggregators or a remote host running Logstash to send Gelf logs to. 

"logConfiguration": {
      "logDriver": "awslogs","fluentd","gelf","json-file","journald","logentries","splunk","syslog","awsfirelens",
      "options": {"string": "string"
        ...},
	"secretOptions": [{
		"name": "string",
		"valueFrom": "string"
	}]
}
logDriver

Type: string

Valid values: "awslogs","fluentd","gelf","json-file","journald","logentries","splunk","syslog","awsfirelens

Required: yes, when logConfiguration is used

The log driver to use for the container. The valid values listed earlier are log drivers that the Amazon ECS container agent can communicate with by default.

For tasks using the Fargate launch type, the supported log drivers are awslogs, splunk, and awsfirelens.

For tasks using the EC2 launch type, the supported log drivers are awslogs, fluentd, gelf, json-file, journald, logentries,syslog, splunk, and awsfirelens.

For more information on using the awslogs log driver in task definitions to send your container logs to CloudWatch Logs, see Using the awslogs log driver.

For more information about using the awsfirelens log driver, see Custom Log Routing.

Note

If you have a custom driver that is not listed, you can fork the Amazon ECS container agent project that is available on GitHub and customize it to work with that driver. We encourage you to submit pull requests for changes that you would like to have included. However, we do not currently provide support for running modified copies of this software.

This parameter requires version 1.18 of the Docker Remote API or greater on your container instance.

options

Type: string to string map

Required: no

The configuration options to send to the log driver.

This parameter requires version 1.19 of the Docker Remote API or greater on your container instance.

secretOptions

Type: object array

Required: no

An object representing the secret to pass to the log configuration. For more information, see Specifying sensitive data.

name

Type: String

Required: Yes

The value to set as the environment variable on the container.

valueFrom

Type: String

Required: Yes

The secret to expose to the log configuration of the container. 

"logConfiguration": {
	"logDriver": "splunk",
	"options": {
		"splunk-url": "https://cloud.splunk.com:8080",
		"splunk-token": "...",
		"tag": "...",
		...
	},
	"secretOptions": [{
		"name": "splunk-token",
		"valueFrom": "/ecs/logconfig/splunkcred"
	}]
}
firelensConfiguration

Type: FirelensConfiguration Object

Required: No

The FireLens configuration for the container. This is used to specify and configure a log router for container logs. For more information, see Custom log routing. 

{
    "firelensConfiguration": {
        "type": "fluentd",
        "options": {
            "KeyName": ""
        }
    }
}
options

Type: String to string map

Required: No

The options to use when configuring the log router. This field is optional and can be used to specify a custom configuration file or to add additional metadata, such as the task, task definition, cluster, and container instance details to the log event. If specified, the syntax to use is "options":{"enable-ecs-log-metadata":"true|false","config-file-type:"s3|file","config-file-value":"arn:aws:s3:::mybucket/fluent.conf|filepath"}. For more information, see Creating a task definition that uses a FireLens configuration.

type

Type: String

Required: Yes

The log router to use. The valid values are fluentd or fluentbit.

Security

privileged

Type: Boolean

Required: no

When this parameter is true, the container is given elevated privileges on the host container instance (similar to the root user).

This parameter maps to Privileged in the Create a container section of the Docker Remote API and the --privileged option to docker run.

Note

This parameter is not supported for Windows containers or tasks using the Fargate launch type. 

"privileged": true|false
user

Type: string

Required: no

The user name to use inside the container. This parameter maps to User in the Create a container section of the Docker Remote API and the --user option to docker run.

You can use the following formats. If specifying a UID or GID, you must specify it as a positive integer.

  • user

  • user:group

  • uid

  • uid:gid

  • user:gid

  • uid:group

Note

This parameter is not supported for Windows containers.

"user": "string"
dockerSecurityOptions

Type: string array

Valid values: "no-new-privileges" | "apparmor:PROFILE" | "label:value" | "credentialspec:CredentialSpecFilePath"

Required: no

A list of strings to provide custom labels for SELinux and AppArmor multi-level security systems. For more information about valid values, see Docker Run Security Configuration. This field is not valid for containers in tasks using the Fargate launch type.

With Windows containers, this parameter can be used to reference a credential spec file when configuring a container for Active Directory authentication. For more information, see Using gMSAs for Windows Containers.

This parameter maps to SecurityOpt in the Create a container section of the Docker Remote API and the --security-opt option to docker. 

"dockerSecurityOptions": ["string", ...]
Note

The Amazon ECS container agent running on a container instance must register with the ECS_SELINUX_CAPABLE=true or ECS_APPARMOR_CAPABLE=true environment variables before containers placed on that instance can use these security options. For more information, see Amazon ECS Container Agent Configuration.

Resource Limits

ulimits

Type: object array

Required: no

A list of ulimits to set in the container. This parameter maps to Ulimits in the Create a container section of the Docker Remote API and the --ulimit option to docker run.

Fargate tasks use the default resource limit values with the exception of the nofile resource limit parameter which Fargate overrides. The nofile resource limit sets a restriction on the number of open files that a container can use. The default nofile soft limit is 1024 and hard limit is 4096 for Fargate tasks. These limits can be adjusted in a task definition if your tasks needs to handle a larger number of files. For more information, see Task resource limits.

This parameter requires version 1.18 of the Docker Remote API or greater on your container instance.

Note

This parameter is not supported for Windows containers.

"ulimits": [
      {
        "name": "core"|"cpu"|"data"|"fsize"|"locks"|"memlock"|"msgqueue"|"nice"|"nofile"|"nproc"|"rss"|"rtprio"|"rttime"|"sigpending"|"stack",
        "softLimit": integer,
        "hardLimit": integer
      }
      ...
    ]
name

Type: string

Valid values: "core" | "cpu" | "data" | "fsize" | "locks" | "memlock" | "msgqueue" | "nice" | "nofile" | "nproc" | "rss" | "rtprio" | "rttime" | "sigpending" | "stack"

Required: yes, when ulimits are used

The type of the ulimit.

hardLimit

Type: integer

Required: yes, when ulimits are used

The hard limit for the ulimit type.

softLimit

Type: integer

Required: yes, when ulimits are used

The soft limit for the ulimit type.

Docker Labels

dockerLabels

Type: string to string map

Required: no

A key/value map of labels to add to the container. This parameter maps to Labels in the Create a container section of the Docker Remote API and the --label option to docker run.

This parameter requires version 1.18 of the Docker Remote API or greater on your container instance. 

"dockerLabels": {"string": "string"
      ...}

Other Container Definition Parameters

The following container definition parameters are able to be used when registering task definitions in the Amazon ECS console by using the Configure via JSON option. For more information, see Creating a task definition.

Linux Parameters

linuxParameters

Type: LinuxParameters object

Required: no

Linux-specific options that are applied to the container, such as KernelCapabilities.

Note

This parameter is not supported for Windows containers.

"linuxParameters": {
      "capabilities": {
        "add": ["string", ...],
        "drop": ["string", ...]
        }
      }
capabilities

Type: KernelCapabilities object

Required: no

The Linux capabilities for the container that are added to or dropped from the default configuration provided by Docker. For more information about the default capabilities and the non-default available capabilities, see Runtime privilege and Linux capabilities in the Docker run reference. For more detailed information about these Linux capabilities, see the capabilities(7) Linux manual page.

add

Type: string array

Valid values: "ALL" | "AUDIT_CONTROL" | "AUDIT_READ" | "AUDIT_WRITE" | "BLOCK_SUSPEND" | "CHOWN" | "DAC_OVERRIDE" | "DAC_READ_SEARCH" | "FOWNER" | "FSETID" | "IPC_LOCK" | "IPC_OWNER" | "KILL" | "LEASE" | "LINUX_IMMUTABLE" | "MAC_ADMIN" | "MAC_OVERRIDE" | "MKNOD" | "NET_ADMIN" | "NET_BIND_SERVICE" | "NET_BROADCAST" | "NET_RAW" | "SETFCAP" | "SETGID" | "SETPCAP" | "SETUID" | "SYS_ADMIN" | "SYS_BOOT" | "SYS_CHROOT" | "SYS_MODULE" | "SYS_NICE" | "SYS_PACCT" | "SYS_PTRACE" | "SYS_RAWIO" | "SYS_RESOURCE" | "SYS_TIME" | "SYS_TTY_CONFIG" | "SYSLOG" | "WAKE_ALARM"

Required: no

The Linux capabilities for the container to add to the default configuration provided by Docker. This parameter maps to CapAdd in the Create a container section of the Docker Remote API and the --cap-add option to docker run.

Note

Tasks launched on Fargate only support adding the SYS_PTRACE kernel capability.

drop

Type: string array

Valid values: "ALL" | "AUDIT_CONTROL" | "AUDIT_WRITE" | "BLOCK_SUSPEND" | "CHOWN" | "DAC_OVERRIDE" | "DAC_READ_SEARCH" | "FOWNER" | "FSETID" | "IPC_LOCK" | "IPC_OWNER" | "KILL" | "LEASE" | "LINUX_IMMUTABLE" | "MAC_ADMIN" | "MAC_OVERRIDE" | "MKNOD" | "NET_ADMIN" | "NET_BIND_SERVICE" | "NET_BROADCAST" | "NET_RAW" | "SETFCAP" | "SETGID" | "SETPCAP" | "SETUID" | "SYS_ADMIN" | "SYS_BOOT" | "SYS_CHROOT" | "SYS_MODULE" | "SYS_NICE" | "SYS_PACCT" | "SYS_PTRACE" | "SYS_RAWIO" | "SYS_RESOURCE" | "SYS_TIME" | "SYS_TTY_CONFIG" | "SYSLOG" | "WAKE_ALARM"

Required: no

The Linux capabilities for the container to remove from the default configuration provided by Docker. This parameter maps to CapDrop in the Create a container section of the Docker Remote API and the --cap-drop option to docker run.

devices

Any host devices to expose to the container. This parameter maps to Devices in the Create a container section of the Docker Remote API and the --device option to docker run.

Note

If you are using tasks that use the Fargate launch type, the devices parameter is not supported.

Type: Array of Device objects

Required: No

hostPath

The path for the device on the host container instance.

Type: String

Required: Yes

containerPath

The path inside the container at which to expose the host device.

Type: String

Required: No

permissions

The explicit permissions to provide to the container for the device. By default, the container has permissions for read, write, and mknod on the device.

Type: Array of strings

Valid Values: read | write | mknod

initProcessEnabled

Run an init process inside the container that forwards signals and reaps processes. This parameter maps to the --init option to docker run.

This parameter requires version 1.25 of the Docker Remote API or greater on your container instance.

maxSwap

The total amount of swap memory (in MiB) a container can use. This parameter will be translated to the --memory-swap option to docker run where the value would be the sum of the container memory plus the maxSwap value.

If a maxSwap value of 0 is specified, the container will not use swap. Accepted values are 0 or any positive integer. If the maxSwap parameter is omitted, the container will use the swap configuration for the container instance it is running on. A maxSwap value must be set for the swappiness parameter to be used.

Note

If you are using tasks that use the Fargate launch type, the maxSwap parameter is not supported.

sharedMemorySize

The value for the size (in MiB) of the /dev/shm volume. This parameter maps to the --shm-size option to docker run.

Note

If you are using tasks that use the Fargate launch type, the sharedMemorySize parameter is not supported.

Type: Integer

swappiness

This allows you to tune a container's memory swappiness behavior. A swappiness value of 0 will cause swapping to not happen unless absolutely necessary. A swappiness value of 100 will cause pages to be swapped very aggressively. Accepted values are whole numbers between 0 and 100. If the swappiness parameter is not specified, a default value of 60 is used. If a value is not specified for maxSwap then this parameter is ignored. This parameter maps to the --memory-swappiness option to docker run.

Note

If you are using tasks that use the Fargate launch type, the swappiness parameter is not supported.

tmpfs

The container path, mount options, and maximum size (in MiB) of the tmpfs mount. This parameter maps to the --tmpfs option to docker run.

Note

If you are using tasks that use the Fargate launch type, the tmpfs parameter is not supported.

Type: Array of Tmpfs objects

Required: No

containerPath

The absolute file path where the tmpfs volume is to be mounted.

Type: String

Required: Yes

mountOptions

The list of tmpfs volume mount options.

Type: Array of strings

Required: No

Valid Values: "defaults" | "ro" | "rw" | "suid" | "nosuid" | "dev" | "nodev" | "exec" | "noexec" | "sync" | "async" | "dirsync" | "remount" | "mand" | "nomand" | "atime" | "noatime" | "diratime" | "nodiratime" | "bind" | "rbind" | "unbindable" | "runbindable" | "private" | "rprivate" | "shared" | "rshared" | "slave" | "rslave" | "relatime" | "norelatime" | "strictatime" | "nostrictatime" | "mode" | "uid" | "gid" | "nr_inodes" | "nr_blocks" | "mpol"

size

The maximum size (in MiB) of the tmpfs volume.

Type: Integer

Required: Yes

Container Dependency

dependsOn

Type: Array of ContainerDependency objects

Required: no

The dependencies defined for container startup and shutdown. A container can contain multiple dependencies. When a dependency is defined for container startup, for container shutdown it is reversed. For an example, see Example: Container dependency.

For tasks using the EC2 launch type, the container instances require at least version 1.26.0 of the container agent to enable container dependencies. However, we recommend using the latest container agent version. For information about checking your agent version and updating to the latest version, see Updating the Amazon ECS Container Agent. If you are using an Amazon ECS-optimized Amazon Linux AMI, your instance needs at least version 1.26.0-1 of the ecs-init package. If your container instances are launched from version 20190301 or later, then they contain the required versions of the container agent and ecs-init. For more information, see Amazon ECS-optimized AMIs.

For tasks using the Fargate launch type, this parameter requires that the task or service uses platform version 1.3.0 or later. 

"dependsOn": [
    {
        "containerName": "string",
        "condition": "string"
    }
]
containerName

Type: String

Required: Yes

The container name that must meet the specified condition.

condition

Type: String

Required: Yes

The dependency condition of the container. The following are the available conditions and their behavior:

  • START – This condition emulates the behavior of links and volumes today. It validates that a dependent container is started before permitting other containers to start.

  • COMPLETE – This condition validates that a dependent container runs to completion (exits) before permitting other containers to start. This can be useful for nonessential containers that run a script and then exit. This condition cannot be set on an essential container.

  • SUCCESS – This condition is the same as COMPLETE, but it also requires that the container exits with a zero status. This condition cannot be set on an essential container.

  • HEALTHY – This condition validates that the dependent container passes its Docker healthcheck before permitting other containers to start. This requires that the dependent container has health checks configured. This condition is confirmed only at task startup.

Container Timeouts

startTimeout

Type: Integer

Required: no

Example values: 120

Time duration (in seconds) to wait before giving up on resolving dependencies for a container. For example, you specify two containers in a task definition with containerA having a dependency on containerB reaching a COMPLETE, SUCCESS, or HEALTHY status. If a startTimeout value is specified for containerB and it does not reach the desired status within that time then containerA will give up and not start. This results in the task transitioning to a STOPPED state.

For tasks using the Fargate launch type, this parameter requires that the task or service uses platform version 1.3.0 or later. If this parameter is not specified, the default value of 3 minutes is used.

For tasks using the EC2 launch type, if the startTimeout parameter is not specified, the value set for the Amazon ECS container agent configuration variable ECS_CONTAINER_START_TIMEOUT is used by default. If neither the startTimeout parameter or the ECS_CONTAINER_START_TIMEOUT agent configuration variable are set, then the default values of 3 minutes for Linux containers and 8 minutes on Windows containers are used. Your container instances require at least version 1.26.0 of the container agent to enable a container start timeout value. However, we recommend using the latest container agent version. For information about checking your agent version and updating to the latest version, see Updating the Amazon ECS Container Agent. If you are using an Amazon ECS-optimized Amazon Linux AMI, your instance needs at least version 1.26.0-1 of the ecs-init package. If your container instances are launched from version 20190301 or later, then they contain the required versions of the container agent and ecs-init. For more information, see Amazon ECS-optimized AMIs.

stopTimeout

Type: Integer

Required: no

Example values: 120

Time duration (in seconds) to wait before the container is forcefully killed if it doesn't exit normally on its own.

For tasks using the Fargate launch type, the task or service requires platform version 1.3.0 or later. The max stop timeout value is 120 seconds and if the parameter is not specified, the default value of 30 seconds is used.

For tasks using the EC2 launch type, if the stopTimeout parameter is not specified, the value set for the Amazon ECS container agent configuration variable ECS_CONTAINER_STOP_TIMEOUT is used by default. If neither the stopTimeout parameter or the ECS_CONTAINER_STOP_TIMEOUT agent configuration variable are set, then the default values of 30 seconds for Linux containers and 30 seconds on Windows containers are used. Container instances require at least version 1.26.0 of the container agent to enable a container stop timeout value. However, we recommend using the latest container agent version. For information about checking your agent version and updating to the latest version, see Updating the Amazon ECS Container Agent. If you are using an Amazon ECS-optimized Amazon Linux AMI, your instance needs at least version 1.26.0-1 of the ecs-init package. If your container instances are launched from version 20190301 or later, then they contain the required versions of the container agent and ecs-init. For more information, see Amazon ECS-optimized AMIs.

System Controls

systemControls

Type: SystemControl object

Required: no

A list of namespaced kernel parameters to set in the container. This parameter maps to Sysctls in the Create a container section of the Docker Remote API and the --sysctl option to docker run.

It is not recommended that you specify network-related systemControls parameters for multiple containers in a single task that also uses either the awsvpc or host network mode for the following reasons:

  • For tasks that use the awsvpc network mode, if you set systemControls for any container it will apply to all containers in the task. If you set different systemControls for multiple containers in a single task, the container that is started last will determine which systemControls take effect.

  • For tasks that use the host network mode, the network namespace systemControls are not supported.

If you are setting an IPC resource namespace to use for the containers in the task, the following will apply to your system controls. For more information, see IPC mode.

  • For tasks that use the host IPC mode, IPC namespace systemControls are not supported.

  • For tasks that use the task IPC mode, IPC namespace systemControls values will apply to all containers within a task.

Note

This parameter is not supported for Windows containers or tasks using the Fargate launch type. 

"systemControls": [
    {
         "namespace":"string",
         "value":"string"
    }
]
namespace

Type: String

Required: no

The namespaced kernel parameter to set a value for.

Valid IPC namespace values: "kernel.msgmax" | "kernel.msgmnb" | "kernel.msgmni" | "kernel.sem" | "kernel.shmall" | "kernel.shmmax" | "kernel.shmmni" | "kernel.shm_rmid_forced", as well as Sysctls beginning with "fs.mqueue.*"

Valid network namespace values: Sysctls beginning with "net.*"

value

Type: String

Required: no

The value for the namespaced kernel parameter specifed in namespace.

Interactive

interactive

Type: Boolean

Required: no

When this parameter is true, this allows you to deploy containerized applications that require stdin or a tty to be allocated. This parameter maps to OpenStdin in the Create a container section of the Docker Remote API and the --interactive option to docker run.

Pseudo Terminal

pseudoTerminal

Type: Boolean

Required: no

When this parameter is true, a TTY is allocated. This parameter maps to Tty in the Create a container section of the Docker Remote API and the --tty option to docker run.

Volumes

When you register a task definition, you can optionally specify a list of volumes to be passed to the Docker daemon on a container instance, which then becomes available for access by other containers on the same container instance.

The following are the types of data volumes that can be used:

  • Docker volumes — A Docker-managed volume that is created under /var/lib/docker/volumes on the host Amazon EC2 instance. Docker volume drivers (also referred to as plugins) are used to integrate the volumes with external storage systems, such as Amazon EBS. The built-in local volume driver or a third-party volume driver can be used. Docker volumes are only supported when running tasks on Amazon EC2 instances. Windows containers only support the use of the local driver. To use Docker volumes, specify a dockerVolumeConfiguration in your task definition. For more information, see Using volumes.

  • Bind mounts — A file or directory on the host machine is mounted into a container. Bind mount host volumes are supported when running tasks on either AWS Fargate or Amazon EC2 instances. To use bind mount host volumes, specify a host and optional sourcePath value in your task definition. For more information, see Using bind mounts.

For more information, see Using data volumes in tasks.

The following parameters are allowed in a container definition:

name

Type: String

Required: No

The name of the volume. Up to 255 letters (uppercase and lowercase), numbers, hyphens, and underscores are allowed. This name is referenced in the sourceVolume parameter of container definition mountPoints object.

host

Required: No

This parameter is specified when using bind mounts. To use Docker volumes, specify a dockerVolumeConfiguration instead. The contents of the host parameter determine whether your bind mount data volume persists on the host container instance and where it is stored. If the host parameter is empty, then the Docker daemon assigns a host path for your data volume, but the data is not guaranteed to persist after the containers associated with it stop running.

Bind mount host volumes are supported when using either the EC2 or Fargate launch types.

Windows containers can mount whole directories on the same drive as $env:ProgramData.

sourcePath

Type: String

Required: No

When the host parameter is used, specify a sourcePath to declare the path on the host container instance that is presented to the container. If this parameter is empty, then the Docker daemon has assigned a host path for you. If the host parameter contains a sourcePath file location, then the data volume persists at the specified location on the host container instance until you delete it manually. If the sourcePath value does not exist on the host container instance, the Docker daemon creates it. If the location does exist, the contents of the source path folder are exported.

dockerVolumeConfiguration

Type: Object

Required: No

This parameter is specified when using Docker volumes. Docker volumes are only supported when running tasks on EC2 instances. Windows containers only support the use of the local driver. To use bind mounts, specify a host instead.

scope

Type: String

Valid Values: task | shared

Required: No

The scope for the Docker volume, which determines its lifecycle. Docker volumes that are scoped to a task are automatically provisioned when the task starts destroyed when the task is cleaned up. Docker volumes that are scoped as shared persist after the task stops.

autoprovision

Type: Boolean

Default value: false

Required: No

If this value is true, the Docker volume is created if it does not already exist. This field is only used if the scope is shared. If the scope is task then this parameter must either be omitted or set to false.

driver

Type: String

Required: No

The Docker volume driver to use. The driver value must match the driver name provided by Docker because it is used for task placement. If the driver was installed using the Docker plugin CLI, use docker plugin ls to retrieve the driver name from your container instance. If the driver was installed using another method, use Docker plugin discovery to retrieve the driver name. For more information, see Docker plugin discovery. This parameter maps to Driver in the Create a volume section of the Docker Remote API and the --driver option to docker volume create.

driverOpts

Type: String

Required: No

A map of Docker driver specific options to pass through. This parameter maps to DriverOpts in the Create a volume section of the Docker Remote API and the --opt option to docker volume create.

labels

Type: String

Required: No

Custom metadata to add to your Docker volume. This parameter maps to Labels in the Create a volume section of the Docker Remote API and the --label option to docker volume create.

efsVolumeConfiguration

Type: Object

Required: No

This parameter is specified when using Amazon EFS volumes.

fileSystemId

Type: String

Required: Yes

The Amazon EFS file system ID to use.

rootDirectory

Type: String

Required: No

The directory within the Amazon EFS file system to mount as the root directory inside the host. If this parameter is omitted, the root of the Amazon EFS volume will be used. Specifying / will have the same effect as omitting this parameter.

Important

If an EFS access point is specified in the authorizationConfig, the root directory parameter must either be omitted or set to / which will enforce the path set on the EFS access point.

transitEncryption

Type: String

Valid values: ENABLED | DISABLED

Required: No

Whether or not to enable encryption for Amazon EFS data in transit between the Amazon ECS host and the Amazon EFS server. Transit encryption must be enabled if Amazon EFS IAM authorization is used. If this parameter is omitted, the default value of DISABLED is used. For more information, see Encrypting Data in Transit in the Amazon Elastic File System User Guide.

transitEncryptionPort

Type: Integer

Required: No

The port to use when sending encrypted data between the Amazon ECS host and the Amazon EFS server. If you do not specify a transit encryption port, it will use the port selection strategy that the Amazon EFS mount helper uses. For more information, see EFS Mount Helper in the Amazon Elastic File System User Guide.

authorizationConfig

Type: Object

Required: No

The authorization configuration details for the Amazon EFS file system.

accessPointId

Type: String

Required: No

The access point ID to use. If an access point is specified, the root directory value in the efsVolumeConfiguration must either be omitted or set to / which will enforce the path set on the EFS access point. If an access point is used, transit encryption must be enabled in the EFSVolumeConfiguration. For more information, see Working with Amazon EFS Access Points in the Amazon Elastic File System User Guide.

iam

Type: String

Valid values: ENABLED | DISABLED

Required: No

Whether or not to use the Amazon ECS task IAM role defined in a task definition when mounting the Amazon EFS file system. If enabled, transit encryption must be enabled in the EFSVolumeConfiguration. If this parameter is omitted, the default value of DISABLED is used. For more information, see IAM Roles for Tasks.

Task placement constraints

When you register a task definition, you can provide task placement constraints that customize how Amazon ECS places tasks.

If you are using the Fargate launch type, task placement constraints are not supported. By default Fargate tasks are spread across Availability Zones.

For tasks that use the EC2 launch type, you can use constraints to place tasks based on Availability Zone, instance type, or custom attributes. For more information, see Amazon ECS task placement constraints.

The following parameters are allowed in a container definition:

expression

Type: string

Required: no

A cluster query language expression to apply to the constraint. For more information, see Cluster query language.

type

Type: string

Required: yes

The type of constraint. Use memberOf to restrict the selection to a group of valid candidates.

Launch types

When you register a task definition, you specify the launch type to use for your task. For more information, see Amazon ECS launch types.

The following parameter is allowed in a task definition:

requiresCompatibilities

Type: string array

Required: no

Valid Values: EC2 | FARGATE

The launch type the task is using. This enables a check to ensure that all of the parameters used in the task definition meet the requirements of the launch type.

Valid values are FARGATE and EC2. For more information about launch types, see Amazon ECS launch types.

Task size

When you register a task definition, you can specify the total cpu and memory used for the task. This is separate from the cpu and memory values at the container definition level. If using the EC2 launch type, these fields are optional. If using the Fargate launch type, these fields are required and there are specific values for both cpu and memory that are supported.

Note

Task-level CPU and memory parameters are ignored for Windows containers. We recommend specifying container-level resources for Windows containers.

The following parameter is allowed in a task definition:

cpu

Type: string

Required: no

Note

This parameter is not supported for Windows containers.

The hard limit of CPU units to present for the task. It can be expressed as an integer using CPU units, for example 1024, or as a string using vCPUs, for example 1 vCPU or 1 vcpu, in a task definition. When the task definition is registered, a vCPU value is converted to an integer indicating the CPU units.

If using the EC2 launch type, this field is optional. If your cluster does not have any registered container instances with the requested CPU units available, the task will fail. Supported values are between 128 CPU units (0.125 vCPUs) and 10240 CPU units (10 vCPUs).

If using the Fargate launch type, this field is required and you must use one of the following values, which determines your range of supported values for the memory parameter:

CPU value

Memory value (MiB)

256 (.25 vCPU)

512 (0.5 GB), 1024 (1 GB), 2048 (2 GB)

512 (.5 vCPU)

1024 (1 GB), 2048 (2 GB), 3072 (3 GB), 4096 (4 GB)

1024 (1 vCPU)

2048 (2 GB), 3072 (3 GB), 4096 (4 GB), 5120 (5 GB), 6144 (6 GB), 7168 (7 GB), 8192 (8 GB)

2048 (2 vCPU)

Between 4096 (4 GB) and 16384 (16 GB) in increments of 1024 (1 GB)

4096 (4 vCPU)

Between 8192 (8 GB) and 30720 (30 GB) in increments of 1024 (1 GB)

memory

Type: string

Required: no

Note

This parameter is not supported for Windows containers.

The hard limit of memory (in MiB) to present to the task. It can be expressed as an integer using MiB, for example 1024, or as a string using GB, for example 1GB or 1 GB, in a task definition. When the task definition is registered, a GB value is converted to an integer indicating the MiB.

If using the EC2 launch type, this field is optional and any value can be used. If a task-level memory value is specified then the container-level memory value is optional. If your cluster does not have any registered container instances with the requested memory available, the task will fail. If you are trying to maximize your resource utilization by providing your tasks as much memory as possible for a particular instance type, see Container Instance Memory Management.

If using the Fargate launch type, this field is required and you must use one of the following values, which determines your range of supported values for the cpu parameter:

Memory value (MiB)

CPU value

512 (0.5 GB), 1024 (1 GB), 2048 (2 GB)

256 (.25 vCPU)

1024 (1 GB), 2048 (2 GB), 3072 (3 GB), 4096 (4 GB)

512 (.5 vCPU)

2048 (2 GB), 3072 (3 GB), 4096 (4GB), 5120 (5 GB), 6144 (6 GB), 7168 (7 GB), 8192 (8 GB)

1024 (1 vCPU)

Between 4096 (4 GB) and 16384 (16 GB) in increments of 1024 (1 GB)

2048 (2 vCPU)

Between 8192 (8 GB) and 30720 (30 GB) in increments of 1024 (1 GB)

4096 (4 vCPU)

Proxy configuration

proxyConfiguration

Type: ProxyConfiguration object

Required: no

The configuration details for the App Mesh proxy.

For tasks using the EC2 launch type, the container instances require at least version 1.26.0 of the container agent and at least version 1.26.0-1 of the ecs-init package to enable a proxy configuration. If your container instances are launched from the Amazon ECS-optimized AMI version 20190301 or later, then they contain the required versions of the container agent and ecs-init. For more information, see Amazon ECS-optimized AMIs.

For tasks using the Fargate launch type, this feature requires that the task or service uses platform version 1.3.0 or later.

Note

This parameter is not supported for Windows containers.

"proxyConfiguration": {
    "type": "APPMESH",
    "containerName": "string",
    "properties": [
        {
           "name": "string",
           "value": "string"
        }
    ]
}
type

Type: String

Value values: APPMESH

Required: No

The proxy type. The only supported value is APPMESH.

containerName

Type: String

Required: Yes

The name of the container that will serve as the App Mesh proxy.

properties

Type: Array of KeyValuePair objects

Required: No

The set of network configuration parameters to provide the Container Network Interface (CNI) plugin, specified as key-value pairs.

  • IgnoredUID – (Required) The user ID (UID) of the proxy container as defined by the user parameter in a container definition. This is used to ensure the proxy ignores its own traffic. If IgnoredGID is specified, this field can be empty.

  • IgnoredGID – (Required) The group ID (GID) of the proxy container as defined by the user parameter in a container definition. This is used to ensure the proxy ignores its own traffic. If IgnoredUID is specified, this field can be empty.

  • AppPorts – (Required) The list of ports that the application uses. Network traffic to these ports is forwarded to the ProxyIngressPort and ProxyEgressPort.

  • ProxyIngressPort – (Required) Specifies the port that incoming traffic to the AppPorts is directed to.

  • ProxyEgressPort – (Required) Specifies the port that outgoing traffic from the AppPorts is directed to.

  • EgressIgnoredPorts – (Required) The egress traffic going to these specified ports is ignored and not redirected to the ProxyEgressPort. It can be an empty list.

  • EgressIgnoredIPs – (Required) The egress traffic going to these specified IP addresses is ignored and not redirected to the ProxyEgressPort. It can be an empty list.

name

Type: String

Required: No

The name of the key-value pair.

value

Type: String

Required: No

The value of the key-value pair.

Other task definition parameters

The following task definition parameters are able to be used when registering task definitions in the Amazon ECS console by using the Configure via JSON option. For more information, see Creating a task definition.

IPC mode

ipcMode

Type: String

Required: No

The IPC resource namespace to use for the containers in the task. The valid values are host, task, or none. If host is specified, then all containers within the tasks that specified the host IPC mode on the same container instance share the same IPC resources with the host Amazon EC2 instance. If task is specified, all containers within the specified task share the same IPC resources. If none is specified, then IPC resources within the containers of a task are private and not shared with other containers in a task or on the container instance. If no value is specified, then the IPC resource namespace sharing depends on the Docker daemon setting on the container instance. For more information, see IPC settings in the Docker run reference.

If the host IPC mode is used, be aware that there is a heightened risk of undesired IPC namespace exposure. For more information, see Docker security.

If you are setting namespaced kernel parameters using systemControls for the containers in the task, the following will apply to your IPC resource namespace. For more information, see System Controls.

  • For tasks that use the host IPC mode, IPC namespace related systemControls are not supported.

  • For tasks that use the task IPC mode, IPC namespace related systemControls will apply to all containers within a task.

Note

This parameter is not supported for Windows containers or tasks using the Fargate launch type.

PID mode

pidMode

Type: String

Required: No

The process namespace to use for the containers in the task. The valid values are host or task. If host is specified, then all containers within the tasks that specified the host PID mode on the same container instance share the same process namespace with the host Amazon EC2 instance. If task is specified, all containers within the specified task share the same process namespace. If no value is specified, the default is a private namespace. For more information, see PID settings in the Docker run reference.

If the host PID mode is used, be aware that there is a heightened risk of undesired process namespace exposure. For more information, see Docker security.

Note

This parameter is not supported for Windows containers or tasks using the Fargate launch type.