System Administration Guide: IP Services

Common Problems When Deploying IPv6

This section describes issues and problems that you might encounter while planning and deploying IPv6 at your site. For actual planning tasks, refer to Chapter 4, Planning an IPv6 Network (Tasks).

IPv4 Router Cannot Be Upgraded to IPv6

If your existing equipment cannot be upgraded, you might have to purchase IPv6-ready equipment. Check the manufacturers' documentation for any equipment-specific procedures you might have to perform to support IPv6.

Certain IPv4 routers cannot be upgraded for IPv6 support. If this situation applies to your topology, physically wire an IPv6 router next to the IPv4 router. Then, you can tunnel from the IPv6 router over the IPv4 router. For tasks for configuring tunnels, refer to Tasks for Configuring Tunnels for IPv6 Support (Task Map).

Problems After Upgrading Services to IPv6

You might encounter the following situations when preparing services for IPv6 support:

Current ISP Does Not Support IPv6

If you want to deploy IPv6 but your current ISP does not offer IPv6 addressing, consider the following alternatives to changing ISPs:

Security Issues When Tunneling to a 6to4 Relay Router

By nature, a tunnel between a 6to4 router and a 6to4 relay router is insecure. Security problems, such as the following, are inherent in such a tunnel:

These problems and other security issues that are inherent with 6to4 relay routers are explained in the Internet Draft, Security Considerations for 6to4. Generally, you should consider enabling support for 6to4 relay routers for the following reasons only:

Known Issues With a 6to4 Router

The following known bugs affect 6to4 configuration:

Implementing Static Routes at the 6to4 Site (Bug ID 4709338)

The following issue occurs on 6to4 sites with routers that are internal to the 6to4 boundary router. When you configure the 6to4 pseudo-interface, the static route 2002::/16 is automatically added to the routing table on the 6to4 router. Bug 4709338 describes a limitation in the Oracle Solaris RIPng routing protocol that prevents this static route from being advertised to the 6to4 site.

Either of the following workarounds are available for Bug 4709338.

Configuring Tunnels with the Same Source Address (Bug ID 4152864)

Bug ID 4152864 describes problems that occur when two tunnels are configured with the same tunnel source address, which is a serious issue for 6to4 tunnels.

Caution – Caution –

Do not configure a 6to4 tunnel and an automatic tunnel (atun) with the same tunnel source address. For information about automatics and the atun command, refer to the tun(7M) man page.