Is there a Pattern for having one machine in a cluster perform an action?

[Guy Matz]

Hi!  I have a few django servers . . .  I would like to run a syncdb in my playbook, but only need/want one of the django servers in the group to run that play . . .  do I need to designate a machine to run that or is there an easier way?

Thanks!!

[Michael Peters]

Ansible 1.7 added the new "run_once" keyword so that a given action
will only run once for that host list.

> --
> You received this message because you are subscribed to the Google Groups
> "Ansible Project" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to ansible-proje...@googlegroups.com.
> To post to this group, send email to ansible...@googlegroups.com.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/ansible-project/0253c2bf-768c-42ce-aa46-e5d0618cd09c%40googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.

[Guy Matz]

Super-sweet!  For anyone who is wondering, the "full" documentation is in here: http://docs.ansible.com/playbooks_delegation.html

Thanks!!!!!

[Michael DeHaan]

run_once does that for a task, yes.

Long-form, may be useful, as well;

# all of em

- hosts: webservers

  tasks:

     - blarg

     - blarg

# just on the head node

- hosts: webservers[0]

  tasks:

    - blarg  

    - blarg

# now some others

- hosts: dbservers

  tasks:

    - blarg

To view this discussion on the web visit https://groups.google.com/d/msgid/ansible-project/efd58a61-94b3-41f5-8c12-843e8f4db16b%40googlegroups.com.