Especially in Leap 42.1 I want to include an additional software repository (eg. Packman, already added to my repositories in “yast2 repositories”) in above yast2 module. Is that possible and which steps are necessary? I tried it by adding an additional tag <extra_url> in /etc/YaST2/control.xml but without success.
I do not quite understand what you want. Yast Onlline Update (or zypper patch) uses the Update repositories that belong to the official openSUSE repositories (wherein no newer versions are offered after the release date).
Packman does not have such an Update repo, thus you can not add it anywhere.
To update to newer versions on the Packman repo, you can use
zypper up -r <alias|name|#>
where <alias|name|#> is one of the ways you canidentify the Packman (or any other) repo. In YaST > Software > Software Management, use the Repositories View, select Packman, right click in the list at right en click: All in this list if a newer version is available.
YOU only consults the Update repos, i.e. oss and non-oss.
What you want, I understand update from all repos, is the way zypper works if you don’t specify any repos:
zypper ref
zypper up
You’ll see that all repos get refreshed and checked for updates. Mind, if you made the vendor change for packages in the Packman repo, these packages will only be updated from the Packman repo.
The desktop option you have is through Yast - Software -Softwaremanager - Package - All packages - Update if a newer version is available. Hit Accept and off you go.
Another option is through the updater applet in the system tray.