[Yum] relationship between up2date and yum repos

[Steven Stromer]

Dear Group,

I hope I am posting to the most appropriate group. There doesn't seem to 
be a list for up2date, so I'm hoping some of you are using Fedora.

I am under the understanding that in versions of Fedora previous to FC4, 
one had to add new repositories manually to /etc/sysconfig/rhn/sources 
in order for them to appear as available channels in up2date (at least, 
this is what my reading so far indicates). However, in FC4, it seems 
that by simply adding a new .repo file to the /etc/yum.repos.d 
directory, the repository becomes available as a new channel in up2date. 
This is a good thing, I would assume.

In my case, I was adding the Dag Wieers Repository, and when I added a 
dag.repo file to /etc/yum.repos.d, it automatically appeared as a 
'repomd' channel in up2date. When I next added a yum pointer to the same 
repository in my sources file, the dag repository appeared twice in 
up2date, once as a 'repomd' channel, and once as a 'yum' channel.

Am I correct in my observations?

If so, would I be correct to assume that it is not necessary to add the 
yum pointer to my sources file, since that the same repository become 
listed as two separate channels in up2date?

If up2date is actively looking for .repo files in the /etc/yum.repos.d 
directory, can this action be toggled on or off in any up2date 
configuration file?

Finally, (and this is probably a REAL newbie question) when I use 
up2date now that the dag repo has been added, it appears that some 
installed packages are looking to the dag repository for updates, when 
the original packages came from the fedora base and extras repos. If I 
want my system to look to the fedora repositories ONLY for updates to 
these packages, is this possible? Even when I uncheck the dag channel 
before retrieving the list of available package updates, it appears that 
some of the packages want to be updated from dag. Have I already allowed 
dag to update some packages that had to be installed due to dependencies 
on the one package I really wanted from dag, thus 'giving them over' to 
dag for control?

I've searched unsuccessfully for answers to these questions. If the 
answers are already posted somewhere, please just point me in the right 
direction.

Thanks,
Steven Stromer