Oracle Cloud Infrastructure API

Oracle Cloud’s REST API for infrastructure automation. Notable for a generous Always Free tier including ARM-based Ampere A1 compute.

Authentication

API requests are signed with an RSA private key. Register the public key in the OCI Console (Identity > Users > API Keys) and note the fingerprint.

# Key fingerprint format
fingerprint: "64:e8:46:46:b2:76:70:4b:0e:0d:a2:b4:25:ff:ce:14"

The OCI CLI handles signing automatically once configured.

Launching an A1 instance

oci compute instance launch \
  --availability-domain "ncBE:US-SANJOSE-1-AD-1" \
  --compartment-id "ocid1.tenancy.oc1..aaaa..." \
  --shape "VM.Standard.A1.Flex" \
  --shape-config '{"ocpus":2,"memoryInGBs":12}' \
  --image-id "ocid1.image.oc1.us-sanjose-1.aaaa..." \
  --subnet-id "ocid1.subnet.oc1.us-sanjose-1.aaaa..." \
  --assign-public-ip true \
  --display-name "a1-free-tier" \
  --ssh-authorized-keys-file ~/.ssh/id_ed25519.pub

Key endpoints

Endpoint	Description
POST /20160918/instances	Launch compute instance
GET /20160918/instances	List instances
GET /20160918/instances/{id}	Instance details
DELETE /20160918/instances/{id}	Terminate instance
POST /20160918/instances/{id}/actions	Instance actions (start/stop)
GET /20160918/shapes	List available shapes
GET /20160918/images	List images
GET /20160918/vnicAttachments	List VNIC attachments

Real-world notes

Availability domains. Use the availability domain name returned for your tenancy and region by oci iam availability-domain list.

Always Free A1. The current allowance for Always Free tenancies is 2 OCPUs and 12 GB memory total. A1 capacity in the home region can be temporarily unavailable. Handle throttling with exponential backoff.

API endpoints. OCI uses service-specific regional endpoints; iaas is one example, not a universal base URL.

Pagination

List operations return an opc-next-page header. Pass it as the page query parameter to fetch the next page.