I am running 12.04 Precise beta (upgraded from 11.10 Oneiric) and I added the following line to my /etc/apt/source.list:
deb http://http.us.debian.org/debian unstable main contrib non-free
In order to get a newer version of a package (octave 3.6) that I needed but was not available in the precise repository.
This worked fine, but now when I want to upgrade there is a large number of packages that need to get updated. I assume this is because sid has newer versions of many of the packages than precise.
I've temporarily disabled the sid repository, and this works fine – however I am curious to know what would happen if I allowed all those upgrades to go through? Would it break my system? Are the structures of Ubuntu Precise and Debian Sid repositories fundamentally different somehow?
Best Answer
You're mixing two different distributions' packages together. For various reasons, this is a bad idea:
Security.
Stability.
Conflicting updates, which you have right now.
If you let above updates go through, you encounter the first two problems, and then you're in deep trouble if say, as an example a kernel update comes through!
Also, this makes getting an accurate bug report or stacktrace almost impossible, if not entirely impossible.
In short, if you need Debian sid, run sid. Otherwise, run Ubuntu, and just add newer software you want to via a PPA or backports.
More explanations here: