New CUDN-wide private addresses

2015-09-25 - News - Tony Finch

You should be aware of our previous announcements about changing the status of to CUDN-wide private address space.

The central name servers now have DNS zones for There are not yet any registrations in this address space, so the zones are currently almost empty. We have updated the name server configuration advice to cover these new zones.

On the CUDN the RFC 1918 address block is divided in two. The bottom half,, is for institution-private usage and is not routed on the CUDN. The top half,, was previously reserved; it has now been re-assigned as CUDN-wide private address space.

To provide DNS for we have a mechanism for conveniently sharing the zone between institution-private and CUDN-wide private uses. The arrangement we are using is similar to the way is divided between the Computer Lab and the rest of the University.

We have two new zones for this address space,


The sample nameserver configuration has been updated to include them.

Institutions that are using the bottom half,, should provide their own version of with DNAME redirections to for the CUDN-wide addresses.