apt-get vs. Ubuntu Update Manager

[Bob Nielsen]

On Thu, Mar 31, 2005 at 02:36:28PM -0500, John DeCarlo wrote:
> On Wed, 30 Mar 2005 20:33:28 -0700, Shawn Christopher
> <schristopheraz at gmail.com> wrote:
> > This afternoon after reading all the E-mail about sound disapearing I
> > decided I wanted to break my system so I was going to do an apt-get
> > dist-upgrade however it came back as nothing needed to be upgraded. OK,
> > fair enough then I ran the Ubuntu Update Manager and it came up with
> > alot of updates. What is the difference? Shouldn't both of them read
> > from the same sources list?
> 
> Shawn, 
> 
> Others have already given you good answers, but I wanted to summarize
> a bit differently.
> 
> 1.  apt-get dist-upgrade - done basically once - when you want to
> change the version of the distribution you are using.  Then you don't
> use it again until it is time to upgrade again.
> 
> 2.  apt-get update - done every day or on a regular basis to update
> the list of packages available
> 
> 3.  apt-get upgrade - this actually compares the packages on your
> system to the new list generated by the update and sets up a list of
> packages to download and install.
> 
> So because I love to break my system and be on the bleeding edge, I
> usually do the following a couple of times a day:
> 
> sudo apt-get update
> sudo apt-get upgrade
> 

Sometimes a new version of a package will add an additional dependency. 
In that case, the listing will show "held-back" packages. Using apt-get
dist-upgrade will usually pull in the dependency, as well as the new
version (sometimes I have to use 'apt-get install', however).

If one is tracking hoary, it probably is a good idea to use 'apt-get
dist-upgrade' on a regular basis until it is released.  In any case, the
process will stop and let you know what it proposes to do which will
allow you to back out, if desired.  Possibly Synaptic or Upgrade-manager 
do the same things, but I've been using apt-get since before they became 
available and have seen no reason to change.