Re-using "register" variable in multiple tasks

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1

I have the following play in a playbook:

  • hosts: talk

gather_facts: false

tasks:

  • name: win update
    win_updates:
    category: [‘SecurityUpdates’,‘CriticalUpdates’,‘Updates’,‘Tools’,‘DefinitionUpdates’,‘UpdateRollups’]
    register: reboot_hint

I’d like to re-use reboot_hint in additional plays in the playbook via “when”, but the playbook ultimately fails after the first “when”, as in:

  • hosts: talk
    gather_facts: false

tasks:

  • name: start Lyris services

win_service: name={{ item }} state=started start_mode=auto
with_items: [“ListManager”, “LyrisAlert”]
when: (lyris_hint.rc == 0) and (reboot_hint.reboot_required == true) # ie, the ListManager service is installed and reboot is required

  • hosts: admin2
    gather_facts: false
    sudo: yes

tasks:

  • nagios: action=downtime minutes=10 author=“Dimitri Yioulos” service=host host={{item}}
    with_items:

  • talk
    when: reboot_hint.reboot_required == true
    delegate_to: admin2

  • nagios: action=downtime minutes=20 author=“Dimitri Yioulos” service=all host={{item}}

with_items:

  • talk
    when: reboot_hint.reboot_required == true
    delegate_to: admin2
    tags:

  • nagios_downtime

  • hosts: talk

gather_facts: false

tasks:

  • name: reboot server
    raw: ‘cmd /c shutdown /r /t 0’
    when: reboot_hint.reboot_required == true

This is another of my Ansible 101 questions; help making it work is appreciated!

2

I’ve found that my register variable only fails when applied to the play involving another host in my playbook. After having poured over lots of posts from various other sources, I saw one that says, “use hostvars to access the register variables from a different host”. If, indeed, that’s the solution, how do I use hostvars to achieve it?

3

hostvars[<otherhost][<varname]

4

Thanks, Brian. OK, I’d like to use that in a “when” with the register variable “reboot_hint.reboot_required == true”. Will the following work?:

when: hostvars[myhost][reboot_hint.reboot_required == true]

5

no, you are conflating several things there

when: hostvars[myhost][‘reboot_hint’][‘reboot_required’]

^ that will execute when reboot_required is true.

6

OK. Here’s what I’m trying to accomplish:

  • hosts: all
    gather_facts: false

tasks:

  • name: win update
    win_updates:
    category: [‘SecurityUpdates’,‘CriticalUpdates’,‘Updates’,‘Tools’,‘DefinitionUpdates’,‘UpdateRollups’]
    register: reboot_hint

  • hosts: admin2
    gather_facts: false
    sudo: yes

tasks:

  • nagios: action=downtime minutes=20 author=“Dimitri Yioulos” service=host host={{item}}
    with_items: “{{ groups[‘lyris’] }}”
    delegate_to: admin2

when: hostvars[myhost][‘reboot_hint’][‘reboot_required’]

tags:

  • nagios_downtime
  • nagios: action=downtime minutes=20 author=“Dimitri Yioulos” service=all host={{item}}
    with_items: “{{ groups[‘lyris’] }}”
    delegate_to: admin2

when: hostvars[myhost][‘reboot_hint’][‘reboot_required’]

Since “reboot_hint” is coming from the previous play, and since the host or group to run the playbook against is defined at the command line, as in: “ansible-playbook -l lyris myplaybook.yml -u myuser”, what do I specify in the [myhost] section? This must be a variable to accept the host name OR group name I specified at the command line, but I don’t know what that would be.

Further, and maybe another post altogether, how do I make the substitution in “with_items: “{{ groups[‘lyris’] }}”” so that I don’t have to change e.g. lyris is I’m specifying another host or group in running the playbook?

With thanks,

Dimitri