Oracle Cloud Infrastructure Repeater

A workaround for the OCI VM.Standard.A1.Flex 'Out of capacity' error.

The Oracle Cloud Infrastructure (OCI) free tier is rather generous at time of writing, if a little oversubscribed. A 4-core, 24GB VPS using ARM processors is available for free, using what OCI call their 'VM.Standard.A1.Flex' shape.

However, messages saying they are 'out of capacity' are common. Some Reddit users have been writing Javascript into their Chrome console to keep pushing the button every 30 seconds for four hours until a VPS is provisioned.

This project takes a similar 'keep nagging' approach, using a different tech stack:

• Docker
• Ubuntu 22.04 (attempts to use Ubuntu 24.xx with OCI CLI were thwarted by the Python ecosystem)
• Terraform (for supplying the provisioning command)
• Go (for running the provisioning command again and again until it gets what it wants)
• OCI CLI (alternative means of provisioning things if you wish)

You can use this project to provision your free virtual private server. You can also keep the container, which comes with Terraform and OCI CLI, in case you want to use those for other provisioning-related purposes.

You will need an Oracle Cloud Infrastructure account set up already. It's worth trying to provision your server through the web interface first.

Prerequisits

To provision the free server

• Docker
• An Oracle Cloud Infrastructure account
• if you you must copy ./config.example to ./config and insert your own details

To use OCI CLI

• You will need to copy the config file inside the resources/ directory: cp config.example config. Edit the config file with the correct data, similarly to the top of your Terraform config, and start the project.

Use

Generate necessary Terraform file

Create a copy of the Terraform example file: ./resources/main.tf.example ./resources/main.tf. There are instructions within it telling you where in the OCI web interface you will need to get the various settings. The top section is mostly identity and authentication related. The bottom section describes your instance. You will need to go to https://cloud.oracle.com/compute/instances/create , configure your desired instance, then select Save as stack to generate the Terraform settings.

A VM.Standard.A1.Flex shape with 4 CPU cores and 24GB of RAM is a popular choice - this is within the free tier at time of writing.

Start Up Container

make setup
make shell

You should now have a shell on the container. Try running:

oci --version

This will verify that the CLI tool is working. It is documented on the Oracle website.

Terraform

Prepare by going to /app/resources/ and running terraform init and terraform plan.

Run terraform apply once. If you get lucky and it works, you're done.

You may well see Error: 500-InternalError, Out of host capacity. however.

Utility to keep trying Terraform

This is in /app/repeat-command/repeat-command. Run it from /app/resources with:

cd /app/resources/
/app/repeat-command/repeat-command --wait=300 --timeout=14400 --command="terraform apply -auto-approve"

It should check every 5 minutes for 4 hours, repeatedly checking to see if there are resources available.

If you prefer using the OCI CLI to provision your server, the command would be:

oci compute instance launch --availability-domain "ad-example" \
    --compartment-id ocid1.compartment.oc1..exampleuniqueID \
    --shape "VM.Standard.A1.Flex" \
    --image-id ocid1.image.oc1..exampleuniqueID \
    --ssh-authorized-keys-file /app/other-files/id_rsa.pub

Good luck, and have fun with the free server.

Clean-up

make cleanup

To clean up the local copy of your secret access credentials securely, use:

shred -uvz [filename]

Bonus Feature: Repeating a Command

Additionally, the container comes with a small Go utility for repeating a command. If you are having problems such as Oracle Cloud Infrastructure not having the capacity you need, you can continually retry. You will find the Go source code locally in ./repeat-command/main.go. The compilation is done in the Dockerfile. You will find the resulting binary in /app/repeat-command/repeat-command on your container.

Remember that any terraform files etc. that you put in ./other-files/ locally will end up at /app/other-files/ on the container.

For example, this command retries every 5 minutes. After 4 hours it dies.

/app/repeat-command/repeat-command --wait=300 --timeout=14400 --command="command-that-doesnt-exist"

You can also kill it with Ctrl + c.

Here is an example of a command you might want to run:

oci compute instance launch --availability-domain "ad-example" \
    --compartment-id ocid1.compartment.oc1..exampleuniqueID \
    --shape "VM.Standard.A1.Flex" \
    --image-id ocid1.image.oc1..exampleuniqueID \
    --ssh-authorized-keys-file /app/other-files/id_rsa.pub

Note that this assumes you have already got an SSH key in your ./other-files/ directory. If not, you will need to put the necessary credentials there and build the container again.