Apache Graceful restart with Ansible

Question

What is ideal ansible way to do a apache graceful restart?

   - name: Restart Apache gracefully 
      command: apachectl -k graceful

Ansible systemd module does the same? If not, what is the difference? Thanks !

- name: Restart apache service.
  systemd:
    name: apache2
    daemon_reload: yes
    state: restarted

Answer 1

What you can do with Ansible is to ensure that all established connections to Apache are closed ( drained in Ansible lingo).

Use the wait_for module with the condition to wait for drained connections on the particular host and port, with the state set to drained . See below:

- name: wait until apache2 connections are drained.
  wait_for:
   host: 0.0.0.0
   port: 80
   state: drained

Note: You can use this for all your Linux network services, which becomes very handy if you want to shutdown services in a particular order in your Ansible playbook.

The wait_for directive is useful to ensuring that Ansible does not run your playbook until specific steps are completed.

Answer 2

There is not support of graceful state at this moment in service or systemd modules because this is quite specific to certain services, status is limited to started , stopped , restarted reloaded and running . So now you need to use a command module as you wrote in the question to perform a graceful restart, this is the only proper solution.

However there is an issue to support custom status , perhaps someone will implement that soon.

Answer 3

The documentation for the Ansible service module is not clearly stating what "reloaded" state does but, I found that for standard Red Hat 7 install using service module "reloaded" state results in a graceful restart.

I was led to this solution by this Server Fault QA

You can verify by getting process list of the httpd processes prior running your playbook which triggers your handler.

ps -ef | grep httpd | grep -v grep

After your playbook runs and handler reloaded state for httpd service shows "changed", re-examine the process list again.

You should see the start times for all the child httpd (non-root) processes have updated while the root owned parent process's start time has stayed the same.

If you also look in the error log you should see an entry containing: "... configured -- resuming normal operations... "

And, finally, you can see this by examining the output of systemctl status for the httpd.service and see the apachectl graceful option was called:

sudo systemctl status httpd.service

My handler now looks like:

- name: "{{ service_name }} restart handler"
  become: yes
  ansible.builtin.service:
    service: "{{ service_name }}"
    # state: restarted
    state: reloaded