Customize Amazon EKS launch templates
AWS Batch on Amazon EKS supports launch templates. There are constraints on what your launch template can do.
Important
AWS Batch runs /etc/eks/bootstrap.sh
. Don't run /etc/eks/bootstrap.sh
in your launch
template or cloud-init user-data scripts. You can add additional parameters besides the
--kubelet-extra-args
parameter to bootstrap.shAWS_BATCH_KUBELET_EXTRA_ARGS
variable in the /etc/aws-batch/batch.config
file. See the
following example for details.
Note
If the launch template is changed after CreateComputeEnvironment is called, UpdateComputeEnvironment must be called to evaluate the version of the launch template for replacement.
Topics
Add kubelet
extra arguments
AWS Batch supports adding extra arguments to the kubelet
command. For the
list of supported parameters, see kubelet
is added to the --node-labels mylabel=helloworld
kubelet
command line.
MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="==MYBOUNDARY==" --==MYBOUNDARY== Content-Type: text/x-shellscript; charset="us-ascii" #!/bin/bash mkdir -p /etc/aws-batch echo AWS_BATCH_KUBELET_EXTRA_ARGS=\"
--node-labels mylabel=helloworld
\" >> /etc/aws-batch/batch.config --==MYBOUNDARY==--
Configure the container runtime
You can use the
AWS Batch
CONTAINER_RUNTIME
environment variable to configure the container runtime on a managed node. The following
example sets the container runtime to containerd
when bootstrap.sh
runs. For more information, see containerd
Note
The CONTAINER_RUNTIME
environment variable is equivalent to the
--container-runtime
option of bootstrap.sh
. For more
information, see Options
MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="==MYBOUNDARY==" --==MYBOUNDARY== Content-Type: text/x-shellscript; charset="us-ascii" #!/bin/bash mkdir -p /etc/aws-batch echo CONTAINER_RUNTIME=containerd >> /etc/aws-batch/batch.config --==MYBOUNDARY==--
Mount an Amazon EFS volume
You can use launch templates to mount volumes to the node. In the following example, the
cloud-config
packages
and runcmd
settings are used. For more information, see
Cloud config
examples
MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="==MYBOUNDARY==" --==MYBOUNDARY== Content-Type: text/cloud-config; charset="us-ascii" packages: - amazon-efs-utils runcmd: - file_system_id_01=fs-abcdef123 - efs_directory=/mnt/efs - mkdir -p ${efs_directory} - echo "${file_system_id_01}:/ ${efs_directory} efs _netdev,noresvport,tls,iam 0 0" >> /etc/fstab - mount -t efs -o tls ${file_system_id_01}:/ ${efs_directory} --==MYBOUNDARY==--
To use this volume in the job, it must be added in the eksProperties parameter to RegisterJobDefinition. The following example is a large portion of the job definition.
{ "jobDefinitionName": "MyJobOnEks_EFS", "type": "container", "eksProperties": { "podProperties": { "containers": [ { "image": "public.ecr.aws/amazonlinux/amazonlinux:2", "command": ["ls", "-la", "/efs"], "resources": { "limits": { "cpu": "1", "memory": "1024Mi" } }, "volumeMounts": [ { "name": "
efs-volume
", "mountPath": "/efs
" } ] } ], "volumes": [ { "name": "efs-volume
", "hostPath": { "path": "/mnt/efs
" } } ] } } }
In the node, the Amazon EFS volume is mounted in the /mnt/efs
directory. In the
container for the Amazon EKS job, the volume is mounted in the /efs
directory.
IPv6 support
AWS Batch supports Amazon EKS clusters that have IPv6 addresses. No customizations are required for AWS Batch support. However, before you begin, we recommend that you review the considerations and conditions that are outlined in Assigning IPv6 addresses to pods and services in the Amazon EKS User Guide.