The updateservicectl tool can be used to fetch Container Linux updates from upstream and push the update payload to AWS S3. This process is documented for a general file server at: CoreUpdate - Air Gapped Package Management
Download the update payload from the upstream public CoreUpdate instance. The command below fetches the update payload for Container Linux release 1632.2.1:
$ updateservicectl --server=https://public.update.core-os.net package download --dir=/packages/ --version=1632.2.1
Now the /packages/ directory contains a JSON file with update metadata and the Gzipped update payload:
$ tree packages
packages
├── e96281a6-d1af-4bde-9a0a-97b76e56dc57_1632.2.1_info.json
└── e96281a6-d1af-4bde-9a0a-97b76e56dc57_1632.2.1_update.gz
0 directories, 2 files
Use the updateservicectl package create bulk command to create the package on a CoreUpdate instance. In the example below, CoreUpdate is running at: http://coreupdate.example.com:8000.
$ updateservicectl --server=http://coreupdate.example.com:8000 --user=admin --key=4025a24d-b1e4-4294-b0ca package create bulk --base-url=https://s3-us-west-1.amazonaws.com/core-update-support --dir=/packages
Note the use of the flags --user and --key these will be required. Most often the user will be admin and the key can be found in the /etc/coreupdate/config.yaml file.
Be certain to format the URL passed to the --base-url flag as described in the AWS document: "AWS S3 Regions and Endpoints".
On successful creation of the package, the output of this command will state where to upload payloads:
2018/02/06 15:59:41 Creating package with AppId=e96281a6-d1af-4bde-9a0a-97b76e56dc57 and Version=1632.2.1
2018/02/06 15:59:41 Package metadata uploaded. Total=1 Errors=0
2018/02/06 15:59:41 Please upload payloads to https://s3-us-west-1.amazonaws.com/core-update-support.
Upload the update package to the S3 bucket:
aws s3 cp /packages/e96281a6-d1af-4bde-9a0a-97b76e56dc57_1632.2.1_update.gz s3://core-update-support
Access is a very important thing to consider. It is required to have a bucket policy that will allow the machines updating to download the payload. A tool such as curl can be used to verify the payload can be fetched:
curl -L https://s3-us-west-1.amazonaws.com/core-update-support/e96281a6-d1af-4bde-9a0a-97b76e56dc57_1632.2.1_update.gz -o test.gz
Consult the document CoreUpdate - Configure Machines for details on configuring a Container Linux host to use CoreUpdate.