HOTFIXES SOP

From time to time we have to quickly patch a problem or issue in applications in our infrastructure. This process allows us to do that and track what changed and be ready to remove it when the issue is fixed upstream.

Ansible based items:

For ansible, they should be placed after the task that installs the package to be changed or modified. Either in roles or tasks.

hotfix tasks should be called "HOTFIX description" They should also link in comments to any upstream bug or ticket. They should also have tags of hotfix

The process is:

  • Create a diff of any files changed in the fix.

  • Check in the _original_ files and change to role/task

  • Check in now your diffs of those same files.

  • ansible will replace the files on the affected machines completely with the fixed versions.

  • If you need to back it out, you can revert the diff step, wait and then remove the first checkin

Example:

<task that installs the httpd package>

#
# install hash randomization hotfix
# See bug https://bugzilla.redhat.com/show_bug.cgi?id=812398
#
- name: hotfix - copy over new httpd init script
  copy: src="{{ files }}/hotfix/httpd/httpd.init" dest=/etc/init.d/httpd
        owner=root group=root mode=0755
  notify:
  - restart apache
  tags:
  - config
  - hotfix
  - apache

Upstream changes

Also, if at all possible a bug should be filed with the upstream application to get the fix in the next version. Hotfixes are something we should strive to only carry a short time.