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Public IP Addresses

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descriptionDescribes the types of public IP addresses and how instances reach the internet.

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Public IP Addresses

Public IP addresses are globally routable IPv4 addresses that allow your instances to communicate with the internet. By default, Atlas Cloud assigns dynamic public IPs to new networks, but you can also acquire static IP addresses for consistent access.

Types of Public IPs

  1. Source NAT IP: The primary IP address assigned to a network or VPC. All outbound traffic from instances in the network will appear to originate from this IP.

    • Port Forwarding: Can be configured on this IP to reach specific internal services.
    • VPN: Often used as the endpoint for Site-to-Site VPN connections.

  2. Additional Public IPs: You can acquire extra IP addresses for specific purposes:

    • Load Balancer VIP: Frontend IP for balancing traffic across multiple backend instances.
    • Static NAT: Maps a public IP directly 1-to-1 to a specific instance (bypassing the virtual router’s port forwarding rules).

Acquiring a Public IP

  1. Navigate to Network > Public IP Addresses.
  2. Click Acquire New IP.
  3. Select the Zone and the Network or VPC to associate it with.
  4. Description: Tag the IP for easier management (e.g., “Web Server Prod”).

Configuring Rules

Once acquired, click on the IP address to configure access. Add the firewall rule before any forwarding or NAT rule: traffic is dropped until the firewall ingress rule exists.

  1. Firewall: Add an ingress rule allowing the specific ports/protocols (e.g., TCP 80, 443) through the network firewall.
  2. Port Forwarding, Load Balancing, or Static NAT: Then add the rule that delivers traffic to your instances:
    • Port Forwarding: Forward external port X to internal port Y on a specific VM.
    • Load Balancing: Distribute incoming traffic on a port to a pool of VMs.
    • Enable Static NAT: Permanently map this IP to a single VM for full inbound/outbound traffic.

Releasing an IP

To stop metering an unused IP address:

  1. Select the IP address.
  2. Click Release IP. Warning: Released IPs are returned to the pool and cannot be recovered. Any associated DNS records must be updated immediately.

Pricing

A public IPv4 address is metered for as long as the address is allocated to your account regardless of whether it is attached or in use. Usage is recorded hourly and invoiced monthly. See atlascloud.is/en/pricing for the current rate.

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