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User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4.3) Gecko/20050104 Red Hat/1.4.3-3.0.7

Description of problem:
The --dry-run flag is not completely honored when using --upgrade-to-release.  While it does not install packages, it does change the registered base channel on RHN, wiping out dependent channels in the process.  This is bad, as attempting to up2date again without changing it back will cause an upgrade, unless something happens to block the upgrade.

Version-Release number of selected component (if applicable):
up2date-4.2.57-2

How reproducible:
Always

Steps to Reproduce:
1. Install RHEL 3 AS, and register with RHN.
2. up2date --dry-run --upgrade-to-release 4AS
3. Log in to RHN and see that your base channel has changed, and you are no longer subscribed to extras.

Actual Results:  My system was changed to an AS 4 system on RHN, though no packages were installed.

Expected Results:  Nothing, besides the list of updated packages and the warnings about dependency problems that should prevent one from upgrading a running RHEL 3 system to RHEL 4 anyway.

Additional info:

While upgrading from RHEL 3 to RHEL 4 isn't something that should be done with up2date, a user could reasonably assume that using the --dry-run flag with --upgrade-to-release to show them what packages are being replaced/obsoleted in the new version is a safe thing to do, and then mess up their system the next time they try to up2date a package.