# OCI Compute for Beginners: Launch Your First Linux Instance

## Introduction

Oracle Cloud Infrastructure (OCI) Compute lets you create virtual machines and bare metal servers for applications, development, and infrastructure workloads. This tutorial walks through provisioning a Linux virtual machine using the OCI Console, from selecting a region and operating system to connecting through SSH.

This guide follows a sample deployment in the **Singapore region**, using **Oracle Linux 9**, a **virtual machine**, an **existing VCN and public subnet**, and SSH key authentication.

## Before you begin

You need an OCI account with permission to create compute instances in the selected compartment, an existing VCN and subnet, and an SSH key pair. If you plan to connect from the internet, the subnet must support public IP assignment, have an appropriate route through an Internet Gateway, and permit SSH access through its network security rules. Check quotas, service limits, and costs before provisioning.

**Example configuration**

| Setting | Selection in this walkthrough |
|---|---|
| OCI region | Singapore |
| Instance type | Virtual machine (VM) |
| Operating system | Oracle Linux 9 |
| Shape family | AMD (example) |
| Shape illustrated | VM.Standard.E5.Flex |
| CPU and memory | 1 OCPU, 12 GB RAM |
| Network | Existing VCN and public subnet |
| Private IP | Automatically assigned |
| Public IP | Automatically assigned |
| Authentication | SSH key pair |
| Initial login user | `opc` |


## Step 1: Open the Compute Instances page

Sign in to the OCI Console and navigate to **Compute → Instances**. Confirm the intended **region** and **compartment**, because both determine where your new instance will be created. Click **Create Instance** to open the launch wizard.

![01-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/fd22abd2-af59-4717-9b74-f59db09b0e08.png)

![02-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/aee64227-f1a3-4d82-b585-5d85da8301a1.png)

## Step 2: Name the instance and select its placement

Enter a meaningful instance name, and verify the compartment. Select an **Availability Domain (AD)** if the region presents that option. In this example Singapore region onlhy has one AD and it is selected.

Under advanced placement settings, you can choose **On-demand capacity** and optionally specify a **Fault Domain**. The example selects Fault Domain 1. If you leave fault domain selection automatic, OCI places the instance in an available fault domain.

![03-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/d6d6d38a-60a4-426d-8609-c5fd3b749aca.png)

## Step 3: Choose Oracle Linux 9

In **Image and shape**, click **Change Image**. Select **Oracle Linux**, browse the available versions, select **Oracle Linux 9**, and confirm with **Select Image**. The operating system image determines the initial boot volume contents and available features.

![04-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/a7461127-5dea-46e2-9209-1b9cb299fa0b.png)

![05-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/fff96663-f8bd-4206-a9a7-63f95ddbb3cd.png)

![06-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/d465dd1d-1fb9-401a-8d83-73c72213fdda.png)

## Step 4: Select the compute shape and resources

Click **Change Shape**. OCI offers **Virtual Machine** and **Bare Metal Machine** instance types, this tutorial uses a virtual machine. Browse the shape families, including **AMD**, **Intel**, **Ampere**, and specialty or previous-generation options.

For a flexible VM shape, expand the shape details and select the desired **OCPU count** and **memory**. Below screenshots illustrate an AMD **VM.Standard.E5.Flex** shape configured with **1 OCPU and 12 GB RAM**. Choose values that suit your workload and budget. Shape availability and limits can vary.

![07-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/5e57a030-2521-4810-bd58-69b85c1d91a7.png)

![08-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/c372bef6-e769-4740-a32a-f5a5edfafaed.png)

![09-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/45b84698-9bc6-404d-9094-b4f0e2457d52.png)

![10-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/0a68f828-90a5-4e2b-a545-da5171a765b8.png)

## Step 5: Review the security options

Proceed to the **Security** section. I will leaves the **Shielded Instance** option disabled and continues with the default selection. For a real deployment, assess whether Shielded Instances or other supported security options are appropriate before proceeding. These options may impose compatibility or operational constraints.

![11-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/777f339b-9f51-4f41-bbe2-88018e789450.png)

## Step 6: Configure the primary VNIC and network

In the **Networking** section, optionally name the primary virtual network interface card (VNIC). Choose **Select existing virtual cloud network**, then select the correct **VCN** and **subnet** from the available lists.

This example uses an existing **public subnet**. For the private IPv4 address, choose **Automatically assign private IPv4 address**. OCI selects an available address from the subnet. You can instead manually request a specific available private address when required.

Enable **Automatically assign public IPv4 address** for the internet accessible example. A public IP alone does not guarantee access: the VCN route table, Internet Gateway, security rules, and server firewall must also allow the intended traffic. A private subnet is generally preferred for workloads that do not require direct internet access.

![12-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/c0ac6560-7838-4ddb-91cf-0938c2ffd4f5.png)

![13-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/b70885c2-2227-4053-9c1c-6c28ebbc9e18.png)

## Step 7: Configure SSH key authentication

OCI uses SSH public-key authentication for Linux instance access. In **Add SSH keys**, either upload or paste your **SSH public key**, or choose **Generate a key pair for me**.

In this example I will use a key pair created with PuTTYgen and pastes the public key into the launch wizard.

If OCI generates a new key pair, download the **private key** and store it securely before continuing. OCI may not let you retrieve that private key later. Never publish or share private keys in a blog or screenshot.

![14-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/4d4e307c-276d-41f0-b5be-9b54b762e58a.png)

![15-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/d16a9415-08eb-4cbf-af48-922b13d851a0.png)

## Step 8: Configure the boot volume

Continue to **Storage**. This example shows the option to specify a custom **boot volume size** and enable **in-transit encryption**. OCI boot volumes are encrypted at rest, depending on the service and configuration, you can use Oracle-managed or customer-managed encryption keys. Choose the boot volume capacity and security settings required for your workload.

Review the final configuration and click **Create**.

![16-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/ee3746fb-0112-4c73-9591-8d4cc3ff5a76.png)

![17-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/bd98c634-b001-4bce-b722-4f1aac64ca60.png)

## Step 9: Monitor provisioning and inspect the instance

After submitting the wizard, OCI shows the provisioning progress in **Work Requests**. Wait until the request reports **Succeeded** and the instance reaches **Running** state.

Open the instance details to confirm the selected image, shape, OCPU and memory configuration, network addresses, and availability domain. Screenshot demonstrates the work request progressing to 100% and shows the resulting instance details.

![18-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/f69d8bef-1abf-4fc9-9006-93757e702fa6.png)

![19-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/4d29dacf-0d5c-48fc-ac5d-892bcf4599d7.png)

![20-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/3017b1aa-75a4-409e-9e31-dcc96a9160cd.png)

![21-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/25411784-c1de-46e6-a8b6-d9419f60abdf.png)

## Step 10: Connect to the Linux instance over SSH

For an Oracle Linux platform image, the default initial user is generally **`opc`**. Connect from an SSH client using the **private key corresponding to the public key supplied during provisioning**:

```bash
ssh -i /path/to/private_key opc@<INSTANCE_PUBLIC_IP>
```

On Linux or macOS, protect the private key file permissions if needed:

```bash
chmod 600 /path/to/private_key
```

Once connected, verify the server:

```bash
hostname
uptime
cat /etc/os-release
```

Screenshot shows an SSH login as `opc`. If the connection fails in your setup, check the public IP, Internet Gateway route, SSH ingress rules (TCP port 22 from your trusted source address), the server firewall rules, and the correct SSH key.

![22-original](https://cdn.hashnode.com/uploads/covers/6acf060ec5c1c1074a0bb596/4d336385-3a48-4f68-8a3f-c755a7f6f4b8.png)

## Conclusion

You have now followed the complete OCI Console workflow to launch an **Oracle Linux 9 VM**, select its compute resources, configure a primary VNIC, set up SSH authentication, provision the boot volume, and verify remote access.

## References

1. [Creating a Compute Instance in OCI](https://docs.oracle.com/en-us/iaas/Content/Compute/Tasks/launchinginstance.htm)
2. [OCI Compute Shapes](https://docs.oracle.com/en-us/iaas/Content/Compute/References/computeshapes.htm)
3. [Connecting to a Linux Instance](https://docs.oracle.com/en-us/iaas/Content/Compute/Tasks/accessinginstance.htm)
4. [Managing Boot Volumes](https://docs.oracle.com/en-us/iaas/Content/Block/Concepts/bootvolumes.htm)
5. [Connecting to an OCI Compute Instance](https://docs.oracle.com/en-us/iaas/Content/Compute/Tasks/accessinginstance.htm)