yum downgrade does not remove new package

Question

Release 1 contains the following packages

Package A-1.0
Package B-1.0

Release 2 contains the following packages

Package A-2.0
Package B-2.0
Package C-2.0

In Release 2 , Package B-1.0 was split into two packages - package B-2.0 and package C-2.0 .

Now when Release 2 is installed, how do I downgrade to Release 1 ?

yum downgrade AB tries to install package B-1.0 which has file conflicts with package C-2.0 .

yum downgrade ABC does not work because there is no older version for Package C .

Is there a single command through which it erases the new package ( package C-2.0 ) and downgrades packages A and B?

Answer 1

If you upgraded several packages and then you want to downgrade just those two, then it cannot be done. Not using just yum (unless you use --nodeps and temporary break deps). There are high level tools like RH Satellite, which can do that.

If you upgrade just those in separate transaction then you can run:

   yum history list
   yum history undo <ID>

or

   yum history undo last

And it will rollback that transaction. Ie in your case downgrade those packages. See man page of yum for details about history command.

Answer 2

It might be too late as you have already released packages A-2.0 and B-2.0, but what you should have done (and can still do if you can delete your A-2.0 and B-2.0 packages):

In spec file of A-2.0 and B-2.0 add: Requires: C

This has multiple advantages you search (and more):

• when updating A and/or B; C will be automatically installed.
• when uninstalling CA and B will be downgraded.

However:

• when downgrading A and B; C will not be uninstalled.

There is an alternative which I use for my projects: I use a meta-package :

• meta-package-1.0: Requires A-1.0, B-1.0, Conflicts C
• meta-package-2.0: Requires A-2.0, B-2.0, C-2.0

(and I use a branch with an unstable meta-package preparing next release: meta-package: Requires A, B)

Answer 3

You can use yum shell to write multiple operations before executing them all in a single transaction.

In your case, you can use the following:

yum shell
yum downgrade A B
yum remove C
run

Answer 4

you just need to use the repo that was referred while executing the earlier yum command.

yum history undo <yum_history_id> --enablerepo=<yum_repo>