Issue
Our application creates a lot of definitions in /etc/services
. We keep a services
file handy with all these definitions so that we can just pipe them into /etc/services
like this:
cp /etc/services /etc/services.stock
cat /path/to/build/services >> /etc/services
It works, but it's not idempotent i.e. running these commands repeatedly will cause the services file to get appended with the info again.
As I work through our Ansible playbooks, I'm trying to figure out how to do this. I could so something like this:
- command: "cat /path/to/build/services >> /etc/services"
but I don't want it to run every time I run the playbook.
Another option is to do something like this:
- name: add services
lineinfile:
state: present
insertafter: EOF
dest: /etc/services
line: "{{ item }}"
with_items:
- line 1
- line 2
- line 3
- line 4
- ...
but this is really slow, because it does each line individually.
Is there a better way? Templates don't help, because they'd totally overwrite the services file, which seems a little rude.
Solution
blockinfile
is a native, idempotent module to ensure a specified set of lines is present (absent) in a file.
Example:
- name: add services
blockinfile:
state: present
insertafter: EOF
dest: /etc/services
marker: "<!-- add services ANSIBLE MANAGED BLOCK -->"
content: |
line 1
line 2
line 3
Answered By - techraf Answer Checked By - Mildred Charles (WPSolving Admin)