[Qgis-user] Ubuntu vivid problem

[Tony Bazeley]

I recently upgrade to 2.8 Wien under Ubuntu trusty which worked well.

However my upgrade to Ubuntu vivid reveals some qgis specific problems 
in that the repository seems incomplete

My sources.list entries are:
deb     http://qgis.org/debian vivid main
deb-src http://qgis.org/debian vivid main

sudo apt-get update | grep qgis yields:

Ign http://qgis.org vivid InRelease
Ign http://qgis.org vivid Release.gpg
Ign http://qgis.org vivid Release
Err http://qgis.org vivid/main Sources
Err http://qgis.org vivid/main amd64 Packages
Err http://qgis.org vivid/main i386 Packages
Ign http://qgis.org vivid/main Translation-en_AU
Ign http://qgis.org vivid/main Translation-en
Ign http://qgis.org vivid/main Translation-en_GB
W: Failed to fetch 
http://qgis.org/debian/dists/vivid/main/source/Sources  404  Not Found
W: Failed to fetch 
http://qgis.org/debian/dists/vivid/main/binary-amd64/Packages 404  Not Found
W: Failed to fetch 
http://qgis.org/debian/dists/vivid/main/binary-i386/Packages  404 Not Found
E: Some index files failed to download. They have been ignored, or old 
ones used instead.

The main ubuntu repositories appear to contain qgis 2.4, which is a 
problem as qgis project files are not backwardly compatible
Does anyone have any idea how this problem might be resolved?

TIA
Tony