Bug 1926261

Summary:	dnf should not allow an installonly_limit less than 2
Product:	Red Hat Enterprise Linux 8	Reporter:	jcastran
Component:	dnf	Assignee:	Marek Blaha <mblaha>
Status:	CLOSED ERRATA	QA Contact:	Jan Blazek <jblazek>
Severity:	high	Docs Contact:
Priority:	high
Version:	8.3	CC:	dstreit, james.antill, mblaha, pkratoch
Target Milestone:	rc	Keywords:	Triaged
Target Release:	8.0
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	dnf-4.7.0-1.el8	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-11-09 19:52:36 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1951409, 1951411
Bug Blocks:

Description jcastran 2021-02-08 14:16:14 UTC

Description of problem:
When the installonly_limit is set to 1, dnf fails to update the kernel and does not clearly indicate why. DNF should not allow for an installonly_limit of 1

Version-Release number of selected component (if applicable):
dnf-4.2.23-4.el8.noarch

How reproducible:
Everytime

Steps to Reproduce:
1. Have a kernel update available or install a lower kernel
2. # yum update kernel --setopt=installonly_limit=1
3.

Actual results:
Error:
 Problem: The operation would result in removing the following protected packages: kernel-core
(try to add '--skip-broken' to skip uninstallable packages or '--nobest' to use not only best candidate packages)


Expected results:
yum/dnf prevents the installonly_limit being set less than 2. 


Additional info:
RHEL 7 implemented this in 2008

https://github.com/rpm-software-management/yum/commit/b31133149f5b25e0fb01d6bfa07f4d6f699c9142

When this is set on RHEL 7, yum stops you.

Options error: Error parsing "installonly_limit = '1'": out of range integer value

Comment 1 Marek Blaha 2021-02-16 08:54:24 UTC

According to `man dnf.conf` (see https://dnf.readthedocs.io/en/latest/conf_ref.html#installonly-limit-label for a html version) values 0 or 1 in installonly_limit configuration option means that unlimited number of installonly packages is being kept. Apparently, due to a bug in dnf only value 0 is accepted as such.
Is fixing the dnf to behave according the documentation acceptable solution? I.e. if installonly_limit is 1, no error is raised and dnf allows any number of kernels installed.

Comment 2 Marek Blaha 2021-02-17 09:09:49 UTC

The other option of fixing it is what you actually proposed - change the documentation that 1 is not allowed value and raise similar error as RHEL 7 did.

Comment 3 jcastran 2021-02-17 12:58:29 UTC

My vote is to change the documentation and not allow a value of 1. 

This would prevent cases where it was assumed 1 meant only 1 kernel is allowed and they inevitably run out of space in /boot. Better to allow 0 to be unlimited, but make 1 output a message telling them they can't do that.

Comment 5 Marek Blaha 2021-03-05 15:59:03 UTC

PR that disallows installonly_limit=1 configuration option - https://github.com/rpm-software-management/libdnf/pull/1155
PR that changes documentation accordingly and prints the warning to the user - https://github.com/rpm-software-management/dnf/pull/1740

Comment 6 Marek Blaha 2021-03-05 16:10:40 UTC

PR with test: https://github.com/rpm-software-management/ci-dnf-stack/pull/970

Comment 16 errata-xmlrpc 2021-11-09 19:52:36 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (Moderate: dnf security and bug fix update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHSA-2021:4464