# Howto execute ansible one host group at a time? **URL:** \ **Category:** Get Help\ **Tags:** galaxy-ng\ **Created:** [January 24, 2026, 10:38am UTC](https://forum.ansible.com/t/howto-execute-ansible-one-host-group-at-a-time/45168 "2026-01-24T10:38:51Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![S1lverhead](https://sea1.discourse-cdn.com/ansible/user_avatar/forum.ansible.com/s1lverhead/32/10170_2.png) [@S1lverhead](https://forum.ansible.com/u/S1lverhead)\ **Post date:** [January 24, 2026, 10:38am UTC](https://forum.ansible.com/t/howto-execute-ansible-one-host-group-at-a-time/45168/1 "2026-01-24T10:38:52Z")
hi, I have a problem with Ansible 2.16.3(and can’t perform upgrade to newer version in an easy way) I didn’t expect to face. I have playbooks I need to execute on multiple host groups but only one host group(HG) at a time(dependencies between services). - Hosts in HG2(50 hosts) can be executed after all hosts in HG1(20) finished. - Hosts in HG3(600 hosts) can be executed after all hosts in HG2(50 hosts) finished. - etc till Hex I have ANSIBLE\_FORKS set to 300 (infra limit). It would be good keep it due to total number of hosts that must be handled. **Problem:** ANSIBLE\_FORKS allows execution of HG1 and HG2 and part of HG3 in parallel to match total 300 and keeps rolling. **Things explored:** - keyword serial but see no option to limit to “one HG at a time up to limit ANSIBLE\_FORKS”. - –limit CLI parameter - doesn’t seem to work. - keyword delegate - works for one host only - import\_task but by the time this is evaluated it’s already running on multiple HGs. - execution strategies available in default installation - host group parameter for play using “HG1:HG2:HG3” and “HG1 HG2 HG3”. In documentation I see no mention of “ansible waits for one HG to finish before next one starts” **Things I’d like to avoid:** - I have a bash script to control Ansible execution. I’d like to avoid running Ansible multiple times in a for loop one HG at a time. It’s stupid to control execution strategy of Ansible from Bash script :-/ - Writing a ton of short plays in one file for every single HG. - using serial and listing it like snippet below. We are talking 20HGs and bunch of different ansible plays. ```auto strategy: linear hosts: - group1 - group2 - group3 serial: - "{{ groups['group1'] | count }}" - "{{ groups['group2'] | count }}" - "{{ groups['group3'] | count }}" ``` **Things I’m thinking about:** - could tags solve this? - could a custom execution strategy solve this? Is it available on Ansible galaxy or somewhere else? Can someone draft it if it must be written? - any other ideas? Can someone suggest a solution? What am I missing? I can’t believe it I can’t find an explicit way to tell ansible “execute next host group once first finished” thank you, Honza ---
**Author:** ![kks](https://sea1.discourse-cdn.com/ansible/user_avatar/forum.ansible.com/kks/32/10352_2.png) [@kks](https://forum.ansible.com/u/kks)\ **Post date:** [January 24, 2026, 10:58am UTC](https://forum.ansible.com/t/howto-execute-ansible-one-host-group-at-a-time/45168/2 "2026-01-24T10:58:36Z")
You can have several plays inside playbook and this is something that might be helful in this case. This is what comes to mind. ```auto --- - name: Run on group 1 ansible.builtin.import_playbook: playbook.yml vars: hosts: group1 - name: Run on group 2 ansible.builtin.import_playbook: playbook.yml vars: hosts: group1 --- # playbook.yml - name: Run tasks hosts: "{{ hosts }}" tasks: .... ``` Did not try this to be honest. ---
**Author:** ![vbotka](https://sea1.discourse-cdn.com/ansible/user_avatar/forum.ansible.com/vbotka/32/359_2.png) [@vbotka](https://forum.ansible.com/u/vbotka)\ **Post date:** [January 24, 2026, 8:33pm UTC](https://forum.ansible.com/t/howto-execute-ansible-one-host-group-at-a-time/45168/3 "2026-01-24T20:33:05Z")
Q: _ **“How to execute Ansible one host group at a time ?”** _ A: Put the code into a role(s) and import them conditionally. For example, given the trivial role _test_ ```console shell > cat roles/test/tasks/main.yml ``` ```yaml - debug: msg: "Running at {{ inventory_hostname }}" ``` , the inventory ```ini [HG1] host_10 host_11 [HG2] host_20 host_21 [HG3] host_30 host_31 ``` , and the playbook ```yaml - name: Import roles conditionally. hosts: all tasks: - import_role: name: test when: inventory_hostname in groups.HG1 - import_role: name: test when: inventory_hostname in groups.HG2 - import_role: name: test when: inventory_hostname in groups.HG3 ``` The play runs as expected ```yaml PLAY [Import roles conditionally.] ********************************************************************************** TASK [test : debug] ************************************************************************************************* ok: [host_10] => msg: Running at host_10 ok: [host_11] => msg: Running at host_11 TASK [test : debug] ************************************************************************************************* ok: [host_20] => msg: Running at host_20 ok: [host_21] => msg: Running at host_21 TASK [test : debug] ************************************************************************************************* ok: [host_30] => msg: Running at host_30 ok: [host_31] => msg: Running at host_31 PLAY RECAP ********************************************************************************************************** host_10 : ok=1 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0 host_11 : ok=1 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0 host_20 : ok=1 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0 host_21 : ok=1 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0 host_30 : ok=1 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0 host_31 : ok=1 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0 ``` Q: _ **“Would loop work?”** _ A: Yes, it would. But, in the loop, you have to use _include\_role_ instead of the _import\_role_. See the difference between the static and dynamic use of the [roles](https://docs.ansible.com/projects/ansible/latest/playbook_guide/playbooks_reuse_roles.html#roles). Create the file _include\_role.yml_ ```yaml - include_role: name: test when: inventory_hostname in groups[item] ``` and iterate the groups’ list ```yaml - name: Include roles conditionally. hosts: all tasks: - include_tasks: include_role.yml loop: [HG1, HG2, HG3] ``` The play runs as expected ```yaml PLAY [Include roles conditionally.] ********************************************************************************* TASK [include_tasks] ************************************************************************************************ included: /export/scratch/vbotka/vbotka.ansible_qa/tasks/so-79874782/include_role.yml for host_10, host_11, host_20, host_21, host_30, host_31 => (item=HG1) included: /export/scratch/vbotka/vbotka.ansible_qa/tasks/so-79874782/include_role.yml for host_10, host_11, host_20, host_21, host_30, host_31 => (item=HG2) included: /export/scratch/vbotka/vbotka.ansible_qa/tasks/so-79874782/include_role.yml for host_10, host_11, host_20, host_21, host_30, host_31 => (item=HG3) TASK [include_role : test] ****************************************************************************************** included: test for host_10, host_11 TASK [test : debug] ************************************************************************************************* ok: [host_10] => msg: Running at host_10 ok: [host_11] => msg: Running at host_11 TASK [include_role : test] ****************************************************************************************** included: test for host_20, host_21 TASK [test : debug] ************************************************************************************************* ok: [host_20] => msg: Running at host_20 ok: [host_21] => msg: Running at host_21 TASK [include_role : test] ****************************************************************************************** included: test for host_30, host_31 TASK [test : debug] ************************************************************************************************* ok: [host_31] => msg: Running at host_31 ok: [host_30] => msg: Running at host_30 PLAY RECAP ********************************************************************************************************** host_10 : ok=5 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0 host_11 : ok=5 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0 host_20 : ok=5 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0 host_21 : ok=5 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0 host_30 : ok=5 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0 host_31 : ok=5 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0 ``` [source code](https://github.com/vbotka/ansible_qa/tree/master/tasks/so-79874782)