Why should I switch to IPv6?

Switch from IPv4 to IPv6

For many, IPv6 is just an IPv4 with longer addresses. But this view is completely wrong. IPv6 is a protocol with many new features. The experiences that someone brings with them from the IPv4 world can only be transferred to IPv6 to a limited extent.

The number of IPv6 users will increase sharply in the future. Especially in Latin America and Africa. The internet infrastructure there is still being expanded. At the same time, the number of users is increasing sharply. And at the same time there is the lowest availability of IPv4 addresses there.

For those who operate or administer networks, it is therefore urgently advisable to deal intensively with IPv6. However, those who have knowledge and experience with IPv4 have only minor advantages. Because IPv6 brings with it many things that are also known from IPv4, nevertheless IPv6 pursues completely different ideas and goals.

When switching or converting from IPv4 to IPv6, it is not a question of replacing IPv4 with IPv6, but of operating IPv6 in addition to IPv4. The parallel operation drives up the effort for network planning, security and configuration. In principle, you have to do every work on the IP level twice. Once for IPv4 and then also for IPv6. The additional protocol initially leads to more work and complexity. You have to take into account that the parallel operation will take several decades. IT managers have to take this into account when planning personnel and costs.

Transition procedure from IPv4 to IPv6

It is practically impossible to update all obsolete devices at once and replace them with IPv6-capable ones. Therefore there are a number of transition procedures that can transmit IPv6 packets over the existing IPv4 infrastructure.

IPv6 capability

In principle, you can no longer avoid IPv6. It is therefore necessary that when purchasing hardware and software, attention must be paid to IPv6 capability. But while you can find pages of information about IPv4 in tenders, operating instructions and documentation, one line only mentions "IPv6 capability". But what does that mean? In principle, "IPv6-capability" or "IPv6-capable" doesn't mean anything.
Many network infrastructure components, such as B. routers and firewalls, can not yet handle IPv6 correctly. You have only implemented part of IPv6.
But even if hardware and software fully support IPv6, companies and users have by no means solved all of the challenges associated with the acquisition, installation and operation of IPv6-compatible components.
Managers and administrators are inevitably breaking new ground with IPv6. Nevertheless, the migration should be pushed forward continuously. This also includes consistently paying attention to IPv6 capability when purchasing new equipment and also checking this in a test position. Not just with routers and the firewall. Even with any other hardware and software.

IPv6 in local networks (LAN)

Switching from IPv4 to IPv6 in a LAN usually works without any problems. IPv6 is already included in Windows Vista, Windows 7 and 8, MacOS and Linux. Users with a current operating system can already use IPv6 in their local network. Distributing devices such as hubs and switches do not matter whether IPv4 or IPv6 is used. They take care of the network communication under the Internet protocol.
Only the DSL and WLAN routers in the private sector have virtually no IPv6 support. This means that IPv6 connections are possible within a local network. In order to be able to establish IPv6 connections to the Internet, IPv6 support in the Internet access router and a "native" IPv6 connection of the Internet provider are required. This means that the Internet access router must receive a global prefix from the provider network and also distribute this in the local network via router advertisement.

IPv6 in the access network (network operator)

Since the end of 2012, Internet connections have been gradually converted to IPv6. The conversion involves parallel operation of IPv4 and IPv6 (dual-stack mode). As the largest network operator, Deutsche Telekom has started this. Other network operators will follow.
Unfortunately, only IPv4-compatible DSL and WLAN routers make the introduction of IPv6 considerably more difficult on the customer side. This requires cumbersome and expensive transition procedures.

IPv6 on the Internet

So that a server in the Internet can be reached via IPv6, the IPv6 address must be entered in the DNS server. In addition, the networks and the stations contacted must be able to use IPv6.
The next problem is routers that inadequately support IPv6. Anyone who seriously wants to use IPv6 needs IPv6 capability on both the LAN and the WAN side.
The main problem, however, are platforms that were developed on the basis of IPv4 and only work with IPv4. Without special IPv6 applications, there will be no pure IPv6 Internet for a long time. Servers that can only be addressed with IPv4 are inaccessible for pure IPv6 users. For reasons of compatibility, IPv4 must be supported for a long time.

DNS and IPv6

So that a server can be reached from outside via IPv6, the AAAA record for the IPv6 address must be entered in the DNS in addition to the existing A record for the IPv4 address.

example.com. MX 10 mx1.example.com example.com. MX 20 mx1.example.com mx1.example.com. A mx1.example.com. AAAA 2001: db8 :: 2 mx2.example.com. A

Switch server services to IPv6

The focus of all server services is the parallel use of IPv6 and IPv4.

When setting up a new server you have to ask yourself how it gets its IPv6 address. Either by hand, DHCPv6 or another central address management. The responsible DNS server, which delivers the corresponding IPv4 address for a host name, must also be addressable via IPv6 and be able to deliver IPv6 addresses. Only then is the following three-step procedure possible.

  • Configuration of IPv6 addresses on the server
  • Activate IPv6 for the individual services
  • Make services accessible via IPv6 via DNS (provide AAAA records with IPv6 addresses)

After setting up the IPv6 addresses and activating IPv6, you should try to establish a connection using the IPv6 address. The easiest way to do this is with a ping. To do this, you should first ping a server that can only be reached via IPv6.
If the ping test worked, you can check the accessibility from the outside. To do this, you ping the newly configured server from an external IPv6-capable Internet connection.
Finally, a port scan should always be carried out for the newly set up IPv6 addresses in order to check whether any ports are open that should not be.

nmap -6 {IPv6 address}


During a transition period you will be confronted with statements such as "The server cannot be reached". In order to be able to consider sources of error caused by IPv4 and IPv6, both an IPv4 and a separate IPv6 test server should be installed so that customers, users and supporters can recognize dual-stack problems and in the combined IPv4 / IPv6 connection. In other words, to find out whether the fault is to be found in the third-party or in-house infrastructure.

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Collection: IPv6

A PDF file of all articles on Internet Protocol Version 6 from this website. The compilation takes into account the introduction to the basics of IPv6 with detailed descriptions and numerous tables and figures. Learn more about the possibilities and relationships in the IPv6 network.

More information and to download