[LINUX] CentOS Clean up old kernels & don't propagate

What is written in this article

• Clean up kernels that increase as you repeat updates
• How to set not to increase too much

Organize too many kernels

• CentOS6 / 7

• Clean up using the package-cleanup command When leaving two kernels from the newest one and erasing the rest

  [user01@centos7 ~]$ sudo package-cleanup --oldkernels --count=2
  

• CentOS8

• Use dnf to remove older packages above installonly_limit There is no kernel-related setting on the command line, but in most cases installonly is set to kernel-related only. Execute remove --oldinstallonly after confirming with dnf repoquery --installonly. However, since CentOS 8 at hand is set to installonly_limit = 3, I feel that it will not be a situation that requires much organization.

  [user01@cent8 ~]$ dnf repoquery --installonly
  [user01@cent8 ~]$ sudo dnf -y remove --oldinstallonly
  

Set so that the number of kernels does not increase too much

• CentOS6 / 7 Specify the number of generations to keep with installonly_limit = in /etc/yum.conf Set to 0 for unlimited. It seems that it is usually set to 5.

  [user01@centos7 ~]$ sudo vi /etc/yum.conf
  [main]
  cachedir=/var/cache/yum/$basearch/$releasever
  keepcache=0
  debuglevel=2
  logfile=/var/log/yum.log
  exactarch=1
  obsoletes=1
  gpgcheck=1
  plugins=1
  installonly_limit=5
  bugtracker_url=http://bugs.centos.org/set_project.php?project_id=23&ref=http://bugs.centos.org/bug_report_page.php?category=yum
  distroverpkg=centos-release
  
  

• CentOS8 Specify the number of generations to keep with installonly_limit = in /etc/dnf/dnf.conf However, setting it to 1,0 is considered unlimited. 2 is the lowest setting value.

  [main]
  gpgcheck=1
  installonly_limit=3
  clean_requirements_on_remove=True
  best=True
  [user01@cent8 ~]$