IP addresses: IPv4, IPv6, reverse DNS and Elastic IPs

Updated 2026-10-30

Every Wolkra server in Frankfurt can have an IPv6 address at no extra cost and an optional primary IPv4 address for €0.89 per month, and you can set reverse DNS for both. For more flexible setups there are floating IPs, which move between servers, and Elastic IPs, which publish a private server.

The address types at a glance

All prices are billed per started hour from your prepaid balance and capped at the monthly price.

IPv6

IPv6 is included with every server. Many modern clients, mobile networks and services prefer IPv6, and for internal tools, APIs or a WireGuard VPN an IPv6 address alone can be enough. Add an AAAA record in your DNS and you are reachable.

Primary IPv4

Most public websites still need IPv4 because many visitors do not have IPv6 yet. A primary IPv4 is assigned to the server when you create it, or later, and costs €0.89 per month. If a server only talks to other servers over a private network, you can skip IPv4 entirely and save the cost.

Reverse DNS (PTR)

Reverse DNS maps an IP address back to a host name. You can set a PTR record for primary IPs and floating IPs in the console or through the API.

It matters most for mail: many receiving servers check that the sending address has a PTR record that matches the host name. Good reverse DNS also makes logs and traceroutes easier to read.

To set it:

1. Point your host name (for example mail.example.com) at the server's IP with an A or AAAA record.
2. Open the server or floating IP in the console.
3. Enter the host name as reverse DNS and save.

Floating IPs

A floating IP is owned by your project, not by a server. Assign it to a server, then move it to another server in seconds for failover, maintenance or a zero-downtime swap.

Elastic IPs

An Elastic IP is a public address that Wolkra translates (NAT) to a server on a private network. The server has only a private address and no public interface of its own, yet it can be reached on the Elastic IP.

This is useful when one specific private server must be reachable from outside, for example a mail relay, a VPN endpoint or a partner integration, while the rest of the stack stays private. For outbound access from many private servers, use a NAT gateway. For incoming web traffic to several servers, use a load balancer.

Managing addresses in the console and API

In the console you can add or remove a primary IPv4, see each server's IPv6 address, create floating and Elastic IPs, assign them and set reverse DNS. The Wolkra API exposes the same actions, so you can automate failover or provision addresses as part of a deployment.

Choosing the right mix

• A public website: IPv6 plus a primary IPv4, with reverse DNS if the server sends mail.
• An internal API or worker: a private network only, with a NAT gateway for updates. No public addresses at all.
• A service that must keep its address across rebuilds: a floating IP.
• One private server that must be reachable: an Elastic IP.
• Several servers sharing incoming traffic: a load balancer with its own public address.

Every option has unmetered traffic with no per-GB fees, so the choice is about design and security, not about counting bandwidth. See the network page for how fair use works.

Limits to know

• An IPv6 address is included; we do not promise a specific prefix size.
• A primary IPv4 belongs to one server.
• Floating and Elastic IPs work in the same location as your servers. Today that is Frankfurt.
• Sending mail from a server is subject to the Acceptable Use Policy. Abuse reports go to [email protected].

Related products

• Network: unmetered bandwidth, IPv4 and IPv6
• Floating IPs
• NAT gateways and private networks
• Load balancers
• Firewalls to control what reaches each address

Get your addresses

Start with IPv6 included and add IPv4 where you need it. Sign up for Wolkra and launch a server in Frankfurt.