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Chapter 40. Managing host groups using Ansible playbooks

This chapter introduces host groups in Identity Management (IdM) and describes using Ansible to perform the following operations involving host groups in Identity Management (IdM):

40.1. Host groups in IdM

IdM host groups can be used to centralize control over important management tasks, particularly access control.

Definition of host groups

A host group is an entity that contains a set of IdM hosts with common access control rules and other characteristics. For example, you can define host groups based on company departments, physical locations, or access control requirements.

A host group in IdM can include:

  • IdM servers and clients
  • Other IdM host groups

Host groups created by default

By default, the IdM server creates the host group ipaservers for all IdM server hosts.

Direct and indirect group members

Group attributes in IdM apply to both direct and indirect members: when host group B is a member of host group A, all members of host group B are considered indirect members of host group A.

40.2. Ensuring the presence of IdM host groups using Ansible playbooks

This section describes how to ensure the presence of host groups in Identity Management (IdM) using Ansible playbooks.

Note

Without Ansible, host group entries are created in IdM using the ipa hostgroup-add command. The result of adding a host group to IdM is the state of the host group being present in IdM. Because of the Ansible reliance on idempotence, to add a host group to IdM using Ansible, you must create a playbook in which you define the state of the host group as present: state: present.

Prerequisites

  • You know the IdM administrator password.
  • You have installed the ansible-freeipa package on the Ansible controller.

Procedure

  1. Create an inventory file, for example inventory.file, and define ipaserver in it with the list of IdM servers to target:

    [ipaserver]
    server.idm.example.com
  2. Create an Ansible playbook file with the necessary host group information. For example, to ensure the presence of a host group named databases, specify name: databases in the - ipahostgroup task. To simplify this step, you can copy and modify the example in the /usr/share/doc/ansible-freeipa/playbooks/user/ensure-hostgroup-is-present.yml file.

    ---
    - name: Playbook to handle hostgroups
      hosts: ipaserver
      become: true
    
      tasks:
      # Ensure host-group databases is present
      - ipahostgroup:
          ipaadmin_password: MySecret123
          name: databases
          state: present

    In the playbook, state: present signifies a request to add the host group to IdM unless it already exists there.

  3. Run the playbook:

    $ ansible-playbook -v -i path_to_inventory_directory/inventory.file path_to_playbooks_directory/ensure-hostgroup-is-present.yml

Verification steps

  1. Log into ipaserver as admin:

    $ ssh admin@server.idm.example.com
    Password:
    [admin@server /]$
  2. Request a Kerberos ticket for admin:

    $ kinit admin
    Password for admin@IDM.EXAMPLE.COM:
  3. Display information about the host group whose presence in IdM you wanted to ensure:

    $ ipa hostgroup-show databases
      Host-group: databases

The databases host group exists in IdM.

40.3. Ensuring the presence of hosts in IdM host groups using Ansible playbooks

This section describes how to ensure the presence of hosts in host groups in Identity Management (IdM) using Ansible playbooks.

Prerequisites

Procedure

  1. Create an inventory file, for example inventory.file, and define ipaserver in it with the list of IdM servers to target:

    [ipaserver]
    server.idm.example.com
  2. Create an Ansible playbook file with the necessary host information. Specify the name of the host group using the name parameter of the ipahostgroup variable. Specify the name of the host with the host parameter of the ipahostgroup variable. To simplify this step, you can copy and modify the examples in the /usr/share/doc/ansible-freeipa/playbooks/hostgroup/ensure-hosts-and-hostgroups-are-present-in-hostgroup.yml file:

    ---
    - name: Playbook to handle hostgroups
      hosts: ipaserver
      become: true
    
      tasks:
      # Ensure host-group databases is present
      - ipahostgroup:
          ipaadmin_password: MySecret123
          name: databases
          host:
          - db.idm.example.com
          action: member

    This playbook adds the db.idm.example.com host to the databases host group. The action: member line indicates that when the playbook is run, no attempt is made to add the databases group itself. Instead, only an attempt is made to add db.idm.example.com to databases.

  3. Run the playbook:

    $ ansible-playbook -v -i path_to_inventory_directory/inventory.file path_to_playbooks_directory/ensure-hosts-or-hostgroups-are-present-in-hostgroup.yml

Verification steps

  1. Log into ipaserver as admin:

    $ ssh admin@server.idm.example.com
    Password:
    [admin@server /]$
  2. Request a Kerberos ticket for admin:

    $ kinit admin
    Password for admin@IDM.EXAMPLE.COM:
  3. Display information about a host group to see which hosts are present in it:

    $ ipa hostgroup-show databases
      Host-group: databases
      Member hosts: db.idm.example.com

The db.idm.example.com host is present as a member of the databases host group.

40.4. Nesting IdM host groups using Ansible playbooks

This section describes ensuring the presence of nested host groups in Identity Management (IdM) host groups using Ansible playbooks.

Prerequisites

Procedure

  1. Create an inventory file, for example inventory.file, and define ipaserver in it with the list of IdM servers to target:

    [ipaserver]
    server.idm.example.com
  2. Create an Ansible playbook file with the necessary host group information. To ensure that a nested host group A exists in a host group B: in the Ansible playbook, specify, among the - ipahostgroup variables, the name of the host group B using the name variable. Specify the name of the nested hostgroup A with the hostgroup variable. To simplify this step, you can copy and modify the examples in the /usr/share/doc/ansible-freeipa/playbooks/hostgroup/ensure-hosts-and-hostgroups-are-present-in-hostgroup.yml file:

    ---
    - name: Playbook to handle hostgroups
      hosts: ipaserver
      become: true
    
      tasks:
      # Ensure hosts and hostgroups are present in existing databases hostgroup
      - ipahostgroup:
          ipaadmin_password: MySecret123
          name: databases
          hostgroup:
          - mysql-server
          - oracle-server
          action: member

    This Ansible playbook ensures the presence of the myqsl-server and oracle-server host groups in the databases host group. The action: member line indicates that when the playbook is run, no attempt is made to add the databases group itself to IdM.

  3. Run the playbook:

    $ ansible-playbook -v -i path_to_inventory_directory/inventory.file path_to_playbooks_directory/ensure-hosts-or-hostgroups-are-present-in-hostgroup.yml

Verification steps

  1. Log into ipaserver as admin:

    $ ssh admin@server.idm.example.com
    Password:
    [admin@server /]$
  2. Request a Kerberos ticket for admin:

    $ kinit admin
    Password for admin@IDM.EXAMPLE.COM:
  3. Display information about the host group in which nested host groups are present:

    $ ipa hostgroup-show databases
      Host-group: databases
      Member hosts: db.idm.example.com
      Member host-groups: mysql-server, oracle-server

The mysql-server and oracle-server host groups exist in the databases host group.

40.5. Ensuring the presence of member managers in IDM host groups using Ansible Playbooks

The following procedure describes ensuring the presence of member managers in IdM hosts and host groups using an Ansible playbook.

Prerequisites

  • You know the IdM administrator password.
  • You have installed the ansible-freeipa package on the Ansible controller.
  • You must have the name of the host or host group you are adding as member managers and the name of the host group you want them to manage.

Procedure

  1. Create an inventory file, for example inventory.file, and define ipaserver in it:

    [ipaserver]
    server.idm.example.com
  2. Create an Ansible playbook file with the necessary host and host group member management information:

    ---
    
    - name: Playbook to handle host group membership management
      hosts: ipaserver
      become: true
    
      tasks:
      - name: Ensure member manager user example_member is present for group_name
          ipahostgroup:
            ipaadmin_password: MySecret123
            name: group_name
            membermanager_user: example_member
    
      - name: Ensure member manager group project_admins is present for group_name
          ipahostgroup:
            ipaadmin_password: MySecret123
            name: group_name
            membermanager_group: project_admins
  3. Run the playbook:

    $ ansible-playbook -v -i path_to_inventory_directory/inventory.file path_to_playbooks_directory/add-member-managers-host-groups.yml

Verification steps

You can verify if the group_name group contains example_member and project_admins as member managers by using the ipa group-show command:

  1. Log into ipaserver as administrator:

    $ ssh admin@server.idm.example.com
    Password:
    [admin@server /]$
  2. Display information about testhostgroup:

    ipaserver]$ ipa hostgroup-show group_name
      Host-group: group_name
      Member hosts: server.idm.example.com
      Member host-groups: testhostgroup2
      Membership managed by groups: project_admins
      Membership managed by users: example_member

Additional resources

  • See ipa hostgroup-add-member-manager --help.
  • See the ipa man page.

40.6. Ensuring the absence of hosts from IdM host groups using Ansible playbooks

This section describes how to ensure the absence of hosts from host groups in Identity Management (IdM) using Ansible playbooks.

Prerequisites

Procedure

  1. Create an inventory file, for example inventory.file, and define ipaserver in it with the list of IdM servers to target:

    [ipaserver]
    server.idm.example.com
  2. Create an Ansible playbook file with the necessary host and host group information. Specify the name of the host group using the name parameter of the ipahostgroup variable. Specify the name of the host whose absence from the host group you want to ensure using the host parameter of the ipahostgroup variable. To simplify this step, you can copy and modify the examples in the /usr/share/doc/ansible-freeipa/playbooks/hostgroup/ensure-hosts-and-hostgroups-are-absent-in-hostgroup.yml file:

    ---
    - name: Playbook to handle hostgroups
      hosts: ipaserver
      become: true
    
      tasks:
      # Ensure host-group databases is absent
      - ipahostgroup:
          ipaadmin_password: MySecret123
          name: databases
          host:
          - db.idm.example.com
          action: member
          state: absent

    This playbook ensures the absence of the db.idm.example.com host from the databases host group. The action: member line indicates that when the playbook is run, no attempt is made to remove the databases group itself.

  3. Run the playbook:

    $ ansible-playbook -v -i path_to_inventory_directory/inventory.file path_to_playbooks_directory/ensure-hosts-or-hostgroups-are-absent-in-hostgroup.yml

Verification steps

  1. Log into ipaserver as admin:

    $ ssh admin@server.idm.example.com
    Password:
    [admin@server /]$
  2. Request a Kerberos ticket for admin:

    $ kinit admin
    Password for admin@IDM.EXAMPLE.COM:
  3. Display information about the host group and the hosts it contains:

    $ ipa hostgroup-show databases
      Host-group: databases
      Member host-groups: mysql-server, oracle-server

The db.idm.example.com host does not exist in the databases host group.

40.7. Ensuring the absence of nested host groups from IdM host groups using Ansible playbooks

This section describes how to ensure the absence of nested host groups from outer host groups in Identity Management (IdM) using Ansible playbooks.

Prerequisites

Procedure

  1. Create an inventory file, for example inventory.file, and define ipaserver in it with the list of IdM servers to target:

    [ipaserver]
    server.idm.example.com
  2. Create an Ansible playbook file with the necessary host group information. Specify, among the - ipahostgroup variables, the name of the outer host group using the name variable. Specify the name of the nested hostgroup with the hostgroup variable. To simplify this step, you can copy and modify the examples in the /usr/share/doc/ansible-freeipa/playbooks/hostgroup/ensure-hosts-and-hostgroups-are-absent-in-hostgroup.yml file:

    ---
    - name: Playbook to handle hostgroups
      hosts: ipaserver
      become: true
    
      tasks:
      # Ensure hosts and hostgroups are absent in existing databases hostgroup
      - ipahostgroup:
          ipaadmin_password: MySecret123
          name: databases
          hostgroup:
          - mysql-server
          - oracle-server
          action: member
          state: absent

    This playbook makes sure that the mysql-server and oracle-server host groups are absent from the databases host group. The action: member line indicates that when the playbook is run, no attempt is made to ensure the databases group itself is deleted from IdM.

  3. Run the playbook:

    $ ansible-playbook -v -i path_to_inventory_directory/inventory.file path_to_playbooks_directory/ensure-hosts-or-hostgroups-are-absent-in-hostgroup.yml

Verification steps

  1. Log into ipaserver as admin:

    $ ssh admin@server.idm.example.com
    Password:
    [admin@server /]$
  2. Request a Kerberos ticket for admin:

    $ kinit admin
    Password for admin@IDM.EXAMPLE.COM:
  3. Display information about the host group from which nested host groups should be absent:

    $ ipa hostgroup-show databases
      Host-group: databases

The output confirms that the mysql-server and oracle-server nested host groups are absent from the outer databases host group.

40.8. Ensuring the absence of IdM host groups using Ansible playbooks

This section describes how to ensure the absence of host groups in Identity Management (IdM) using Ansible playbooks.

Note

Without Ansible, host group entries are removed from IdM using the ipa hostgroup-del command. The result of removing a host group from IdM is the state of the host group being absent from IdM. Because of the Ansible reliance on idempotence, to remove a host group from IdM using Ansible, you must create a playbook in which you define the state of the host group as absent: state: absent.

Prerequisites

  • You know the IdM administrator password.
  • You have installed the ansible-freeipa package on the Ansible controller.

Procedure

  1. Create an inventory file, for example inventory.file, and define ipaserver in it with the list of IdM servers to target:

    [ipaserver]
    server.idm.example.com
  2. Create an Ansible playbook file with the necessary host group information. To simplify this step, you can copy and modify the example in the /usr/share/doc/ansible-freeipa/playbooks/user/ensure-hostgroup-is-absent.yml file.

    ---
    - name: Playbook to handle hostgroups
      hosts: ipaserver
      become: true
    
      tasks:
      - Ensure host-group databases is absent
        ipahostgroup:
          ipaadmin_password: MySecret123
          name: databases
          state: absent

    This playbook ensures the absence of the databases host group from IdM. The state: absent means a request to delete the host group from IdM unless it is already deleted.

  3. Run the playbook:

    $ ansible-playbook -v -i path_to_inventory_directory/inventory.file path_to_playbooks_directory/ensure-hostgroup-is-absent.yml

Verification steps

  1. Log into ipaserver as admin:

    $ ssh admin@server.idm.example.com
    Password:
    [admin@server /]$
  2. Request a Kerberos ticket for admin:

    $ kinit admin
    Password for admin@IDM.EXAMPLE.COM:
  3. Display information about the host group whose absence you ensured:

    $ ipa hostgroup-show databases
    ipa: ERROR: databases: host group not found

The databases host group does not exist in IdM.

40.9. Ensuring the absence of member managers from IdM host groups using Ansible playbooks

The following procedure describes ensuring the absence of member managers in IdM hosts and host groups using an Ansible playbook.

Prerequisites

  • You know the IdM administrator password.
  • You have installed the ansible-freeipa package on the Ansible controller.
  • You must have the name of the user or user group you are removing as member managers and the name of the host group they are managing.

Procedure

  1. Create an inventory file, for example inventory.file, and define ipaserver in it:

    [ipaserver]
    server.idm.example.com
  2. Create an Ansible playbook file with the necessary host and host group member management information:

    ---
    
    - name: Playbook to handle host group membership management
      hosts: ipaserver
      become: true
    
      tasks:
      - name: Ensure member manager host and host group members are absent for group_name
        ipahostgroup:
          ipaadmin_password: MySecret123
          name: group_name
          membermanager_user: example_member
          membermanager_group: project_admins
          action: member
          state: absent
  3. Run the playbook:

    $ ansible-playbook -v -i path_to_inventory_directory/inventory.file path_to_playbooks_directory/ensure-member-managers-host-groups-are-absent.yml

Verification steps

You can verify if the group_name group does not contain example_member or project_admins as member managers by using the ipa group-show command:

  1. Log into ipaserver as administrator:

    $ ssh admin@server.idm.example.com
    Password:
    [admin@server /]$
  2. Display information about testhostgroup:

    ipaserver]$ ipa hostgroup-show group_name
      Host-group: group_name
      Member hosts: server.idm.example.com
      Member host-groups: testhostgroup2

Additional resources

  • See ipa hostgroup-add-member-manager --help.
  • See the ipa man page.