How to run only one task in ansible playbook?

Question

Is there a way to only run one task in ansible playbook?

For example, in roles/hadoop_primary/tasks/hadoop_master.yml. I have "start hadoop jo

Answer 1

are you familiar with handlers? I think it's what you are looking for. Move the restart from hadoop_master.yml to roles/hadoop_primary/handlers/main.yml:

- name: start hadoop jobtracker services
  service: name=hadoop-0.20-mapreduce-jobtracker state=started

and now call use notify in hadoop_master.yml:

- name: Install the namenode and jobtracker packages
  apt: name={{item}} force=yes state=latest
  with_items: 
   - hadoop-0.20-mapreduce-jobtracker
   - hadoop-hdfs-namenode
   - hadoop-doc
   - hue-plugins
  notify: start hadoop jobtracker services