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  quot start hadoop job tracker services quot  task   Can I just run that one task  hadoop master yml file    Playbook for  Hadoop master servers  - 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  - name  start hadoop jobtracker services   service  name hadoop-0 20-mapreduce-jobtracker state started   tags     debug

User · Answer

FWIW with Ansible 2 2 one can use include role   playbook test yml   - name  test   hosts      - 127 0 0 1   connection  local   tasks      - include role          name  test         tasks from  other   then in roles test tasks other yml   - name  say something else   shell  echo  I m the other guy    And invoke the playbook with  ansible-playbook test yml to get   TASK  test   say something else                changed   127 0 0 1

User · Answer

I would love the ability to use a role as a collection of tasks such that  in my playbook  I can choose which subset of tasks to run  Unfortunately  the playbook can only load them all in and then you have to use the --tags option on the cmdline to choose which tasks to run  The problem with this is that all of the tasks will run unless you remember to set --tags or --skip-tags   I have set up some tasks  however  with a when  clause that will only fire if a var is set   e g      role stuff tasks main yml - name  do stuff   when  stuff default false    Now  this task will not fire by default  but only if I set the stuff true    ansible-playbook -e    stuff  true     or in a playbook   roles  -   role   stuff    stuff  true

User · Answer

There is a way  although not very elegant    ansible-playbook roles hadoop primary tasks hadoop master yml --step --start-at-task  start hadoop jobtracker services  You will get a prompt  Perform task  start hadoop jobtracker services  y n c  Answer y You will get a next prompt  press Ctrl-C

User · Answer

See my answer here  Run only one task and handler from ansible playbook It is possible to run separate role  from roles  dir   ansible -i stage yml -m include role -a name create-os-user localhost  and separate task file  ansible -i stage yml -m include tasks -a file tasks create-os-user yml localhost  If you externalize tasks from role to root tasks  directory  reuse is achieved by import tasks           tasks create-os-user yml  you can run it independently from playbook role

User · Answer

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

User · Answer

You should use tags  as documented in https   docs ansible com ansible latest user guide playbooks tags html  If you have a large playbook it may become useful to be able to run a specific part of the configuration without running the whole playbook  Both plays and tasks support a    tags     attribute for this reason  Example  tasks       - yum  name    item    state installed       with items           - httpd          - memcached       tags           - packages      - template  src templates src j2 dest  etc foo conf       tags           - configuration  If you wanted to just run the    configuration    and    packages    part of a very long playbook  you could do this  ansible-playbook example yml --tags  quot configuration packages quot   On the other hand  if you want to run a playbook without certain tasks  you could do this  ansible-playbook example yml --skip-tags  quot notification quot   You may also apply tags to roles  roles    -   role  webserver  port  5000  tags     web    foo       And you may also tag basic include statements  - include  foo yml tags web foo  Both of these have the function of tagging every single task inside the include statement

User · Answer

This can be easily done using the tags  The example of tags is defined below    --- hosts  localhost tasks   - name  Creating s3Bucket    s3 bucket          name  ansiblebucket1234567890    tags          - createbucket   - name  Simple PUT operation    aws s3         bucket  ansiblebucket1234567890        object   my desired key txt        src   etc ansible myfile txt        mode  put    tags        - putfile   - name  Create an empty bucket    aws s3         bucket  ansiblebucket12345678901234        mode  create        permission  private    tags         - emptybucket   to execute the tags we use the command  ansible-playbook creates3bucket yml --tags  createbucket putfile

[ansible] How to run only one task in ansible playbook?

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