Quick Hands-on Guide To Creating Oracle Singapore VPS Instances And Network Configuration

1.

Preparation and account registration

- Register an Oracle Cloud account to complete email verification and identity verification (if credit card verification is needed, follow the prompts).
- Log in to the console and make sure the Region in the upper right corner is set to "ap-singapore-1 (Singapore)".
- Prepare a local SSH key pair (if none available, run Linux/macOS: ssh-keygen -t rsa -b 4096 -f ~/.ssh/oci_key), and remember the private key path and public key content.

2.

Create an instance: Select the image and calculate specifications

- On the left side of the console, select Compute → Instances → Create Instance.
- Enter the instance name, and select Compartment as default or custom.
- For images, choose Ubuntu/CentOS/Oracle Linux, etc.; Ubuntu LTS is recommended.
- For Shape, select VM.Standard or Ampere series (for free credits, always free options can be selected for the Always Free version e.g., VM.Standard.E2.1.Micro), and confirm OCPU and memory.

3.

Set the SSH key and log in to the user

- On the Create Instance page, scroll down to "Add SSH keys" and paste the locally generated public key (~/.ssh/oci_key.pub) or upload it.
- Note that the default username for the image is usually ubuntu, while Oracle Linux uses opc. Example SSH command: ssh -i ~/.ssh/oci_key ubuntu@<公网IP>.

4.

Network configuration: Create VCN and subnets (automatic or manual).

- On the instance creation interface, you can select "Create Virtual Cloud Network" to automatically create VCN/subnet/IGW/Route Tables.
- If manual: Networking → Virtual Cloud Networks → Create VCN, fill in CIDR (e.g., 10.0.0.0/16), create a public subnet (e.g., 10.0.0.0/24).
- Create an Internet Gateway and add 0.0.0.0/0 to the IGW in the Route Table to ensure the subnet is associated with the routing table.

5.

Security settings: Security list or Network Security Group (NSG

). - For public subnets, edit Security Lists or NSG and add the Ingress rule: TCP 22 (SSH) source 0.0.0.0/0, TCP 80, 443 source 0.0.0.0/0.
- If only your IP is allowed to log in, you can change port 22 to your public IP/32. Generally, all exits are allowed.

6.

Allocate public network addresses and elastic IPs

- When creating an instance, you can choose to Assign a public IP (automatic assignment).
- If you need a persistent public IP, navigate to Network → Public IPs → Reserve Public IP, select Regional or Ephemeral as type, and assign them to the VNIC of the instance.
- In the instance details, find Primary VNIC, click Attach/Detach Public IP, and select the reserved Public IP.

7.

First login and system initialization

- Log in with SSH: ssh -i ~/.ssh/oci_key ubuntu@PUBLIC_IP. For first-time login, it is recommended to run: sudo apt update & sudo apt upgrade -y.
- Modify hostname:sudo hostnamectl set-hostname my-vps; Edit the /etc/hosts mapping.
- Set time zones and locale (e.g., sudo timedatectl set-timezone Asia/Singapore).

8.

Install commonly used services and firewall configuration

- Example of installing Nginx: sudo apt install nginx -y; Start and set boot auto-start: sudo systemctl enable --now nginx.
- Configure UFW firewall: sudo ufw allow OpenSSH; sudo ufw allow http; sudo ufw allow https; sudo ufw enable。 Confirmation rule: sudo ufw status verbose.

9.

Mount data disks and persistent storage

- Console Volumes → Block Volumes → Create Block Volume, select size and available domain.
- On the instance page, Attach Block Volume. After SSH begins, execute: lsblk to confirm the new drive (e.g., /dev/sdb), format: sudo mkfs.ext4 /dev/sdb1 (or /dev/sdb), create mount point sudo mkdir /data, mount sudo mount /dev/sdb1 /data.
- Edit /etc/fstab to add UUID mount to maintain reboot persistence: sudo blkid obtains UUID, adds a line: UUID=xxxx /data ext4 defaults, nofail 0 2.

10.

Backup and snapshot management

- It is recommended to perform regular backup/Block Volume snapshots on important disks: Block Volumes → Click Volume → Create Backup.
- You can use OCI's built-in Backup policy or automate the creation of snapshots and upload objects for storage using custom scripts combined with OCI CLI.

11.

Common troubleshooting and troubleshooting

- Unable to SSH: Check whether the instance VNIC has a public IP, whether Security List/NSG has enabled port 22, and whether the local private key permission is 600 (chmod 600 ~ /.ssh/oci_key).
- Network inaccessibility: Check whether the Route Table has 0.0.0.0/0 to IGW, and whether the subnet is a public subnet.

12.

Performance and cost control recommendations

- For low-traffic testing, you can choose Always Free instances or low-end Shapes, monitor usage, and set budget alerts (Billing → Budgets).
- Production environments recommend using Monitoring and Alarms to monitor CPU, network, and disk IO, and automatically scale up or replace higher-spec instances when necessary.

13.

Q: How do I configure domain resolution to an instance on a Singapore VPS >oracle - Point the domain service provider's A record to the Public IP you hold at OCI; If using OCI's DNS service, go to DNS Management to create a zone and add A records, pointing the records to the instance's public IP address. Note that DNS activation has TTL delays.

14.

Q: If the instance needs to provide HTTPS services externally, how should the certificate be configured?

- It is recommended to use Let's Encrypt to install certbot (sudo apt install certbot python3-certbot-nginx), run sudo certbot --nginx -d yourdomain.com follow the prompts to apply and configure Nginx automatically. Remember to open port 443 in the security group and regularly check for auto-renewal (certbot renew).

15

. Q: How can I minimize security risks and regularly maintain my Oracle Singapore VPS?

- Regularly update systems and applications (sudo apt update & sudo apt upgrade -y), disable password login using only SSH keys, close unnecessary ports, and enable UFW and Fail2Ban to restrict brute-force attacks; Set backup policies and monitor bills and alerts.