Dualstack Networking
Summary
Support proper dual stack networking. All major system services and user applications should work with both IPv4 and IPv6. All of them should also be able to cope with multiple addresses per hostname via proper use of getaddrinfo().
Owner
- Name: Pavel Šimerda
- Email: psimerda at redhat.com
- Name: David Jaša
- Email: djasa at redhat.com
- Name Tore Anderson
- Email: tore at fud.no
Current status
- Targeted release: Fedora 19
Detailed description
Fedora supports dualstack global networking. That means the computer with Fedora is connected to internet using both IPv4 and IPv6 protocols. But many important system services and applications eitherdon't do IPv6, do it incorrectly, or don't cope with various network conditions.
Unfortunately, while trying to improve IPv6 support, some IPv4 use cases became broken as well. That's why the goal of this feature is not only to support IPv4, but to support all possible real-world cases.
Dualstack-ready software must cope with all possible scenarios including IPv4-only connectivity, IPv6-only connectivity and dual connectivity. The software must also cope with node-local (aka localhost) networking, which as been used by software for decades.
Though it would be nice to have all applications in Fedora fixed to work in any of the scenarios, it is not feasible to test that. Therefore this bug report is about major software used in servers, desktops and laptops. The list of such applications will be completed over the time.
Bugs related to dualstack networking should be added to the following tracker bug:
http://bugzilla.redhat.com/show_bug.cgi?id=883152
Also see: https://bugzilla.redhat.com/show_bug.cgi?id=ipv6blocker
Benefit to Fedora
One of Fedora's goals is to be a modern linux distribution that will work in modern environments. For this to be achieved, proper IPv4-only support and proper dualstack support is a MUST. IPv6-only use cases are rare but may become more common at any time. It's better to be prepared for those, too.
Scope
Any software commonly used on day-to-day basis should be correctly handling IPv4-only, IPv6-only and dualstack use cases.
Libraries
- glibc: name resolution must work properly
- glib: provides networking API for applications
System services
- knfsd
Applications
Network testing tools
pingdoesn't support IPv6 addresses nor hostnamestcpdumpdoesn't support IPv6 hostnames
How to test
This is the most difficult part. We are going to combine the following approaches to testing:
- Everyday use of Fedora in various network environments
- Testing the tracked bug reports
- Specific tests, e.g. for
getaddrinfo()
User experience
Dependencies
Contingency plan
This feature is about fixing all important parts of the distribution. Therefore even partial accomplishment is good and this feature can be moved to the next Fedora release.