Chapter 2. Managing local storage by using RHEL system roles
To manage LVM and local file systems (FS) by using Ansible, you can use the storage
role, which is one of the RHEL system roles available in RHEL 8.
Using the storage
role enables you to automate administration of file systems on disks and logical volumes on multiple machines and across all versions of RHEL starting with RHEL 7.7.
For more information about RHEL system roles and how to apply them, see Introduction to RHEL system roles.
2.1. Creating an XFS file system on a block device by using the storage
RHEL system role
The example Ansible playbook applies the storage
role to create an XFS file system on a block device using the default parameters.
The storage
role can create a file system only on an unpartitioned, whole disk or a logical volume (LV). It cannot create the file system on a partition.
Prerequisites
- You have prepared the control node and the managed nodes
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudo
permissions on them.
Procedure
Create a playbook file, for example
~/playbook.yml
, with the following content:--- - hosts: managed-node-01.example.com roles: - rhel-system-roles.storage vars: storage_volumes: - name: barefs type: disk disks: - sdb fs_type: xfs
-
The volume name (
barefs
in the example) is currently arbitrary. Thestorage
role identifies the volume by the disk device listed under thedisks:
attribute. -
You can omit the
fs_type: xfs
line because XFS is the default file system in RHEL 8. To create the file system on an LV, provide the LVM setup under the
disks:
attribute, including the enclosing volume group. For details, see Creating or resizing a logical volume by using the storage RHEL system role.Do not provide the path to the LV device.
-
The volume name (
Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.yml
Note that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook ~/playbook.yml
Additional resources
-
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file -
/usr/share/doc/rhel-system-roles/storage/
directory
2.2. Persistently mounting a file system by using the storage
RHEL system role
The example Ansible applies the storage
role to immediately and persistently mount an XFS file system.
Prerequisites
- You have prepared the control node and the managed nodes
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudo
permissions on them.
Procedure
Create a playbook file, for example
~/playbook.yml
, with the following content:--- - hosts: managed-node-01.example.com roles: - rhel-system-roles.storage vars: storage_volumes: - name: barefs type: disk disks: - sdb fs_type: xfs mount_point: /mnt/data mount_user: somebody mount_group: somegroup mount_mode: 0755
-
This playbook adds the file system to the
/etc/fstab
file, and mounts the file system immediately. -
If the file system on the
/dev/sdb
device or the mount point directory do not exist, the playbook creates them.
-
This playbook adds the file system to the
Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.yml
Note that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook ~/playbook.yml
Additional resources
-
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file -
/usr/share/doc/rhel-system-roles/storage/
directory
2.3. Creating or resizing a logical volume by using the storage
RHEL system role
Use the storage
role to perform the following tasks:
- To create an LVM logical volume in a volume group consisting of many disks
- To resize an existing file system on LVM
- To express an LVM volume size in percentage of the pool’s total size
If the volume group does not exist, the role creates it. If a logical volume exists in the volume group, it is resized if the size does not match what is specified in the playbook.
If you are reducing a logical volume, to prevent data loss you must ensure that the file system on that logical volume is not using the space in the logical volume that is being reduced.
Prerequisites
- You have prepared the control node and the managed nodes
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudo
permissions on them.
Procedure
Create a playbook file, for example
~/playbook.yml
, with the following content:--- - name: Manage local storage hosts: managed-node-01.example.com tasks: - name: Create logical volume ansible.builtin.include_role: name: rhel-system-roles.storage vars: storage_pools: - name: myvg disks: - sda - sdb - sdc volumes: - name: mylv size: 2G fs_type: ext4 mount_point: /mnt/data
The settings specified in the example playbook include the following:
size: <size>
- You must specify the size by using units (for example, GiB) or percentage (for example, 60%).
For details about all variables used in the playbook, see the
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file on the control node.Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.yml
Note that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook ~/playbook.yml
Verification
Verify that specified volume has been created or resized to the requested size:
# ansible managed-node-01.example.com -m command -a 'lvs myvg'
Additional resources
-
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file -
/usr/share/doc/rhel-system-roles/storage/
directory
2.4. Enabling online block discard by using the storage
RHEL system role
You can mount an XFS file system with the online block discard option to automatically discard unused blocks.
Prerequisites
- You have prepared the control node and the managed nodes
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudo
permissions on them.
Procedure
Create a playbook file, for example
~/playbook.yml
, with the following content:--- - name: Manage local storage hosts: managed-node-01.example.com tasks: - name: Enable online block discard ansible.builtin.include_role: name: rhel-system-roles.storage vars: storage_volumes: - name: barefs type: disk disks: - sdb fs_type: xfs mount_point: /mnt/data mount_options: discard
For details about all variables used in the playbook, see the
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file on the control node.Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.yml
Note that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook ~/playbook.yml
Verification
Verify that online block discard option is enabled:
# ansible managed-node-01.example.com -m command -a 'findmnt /mnt/data'
Additional resources
-
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file -
/usr/share/doc/rhel-system-roles/storage/
directory
2.5. Creating and mounting an Ext4 file system by using the storage
RHEL system role
The example Ansible playbook applies the storage
role to create and mount an Ext4 file system.
Prerequisites
- You have prepared the control node and the managed nodes
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudo
permissions on them.
Procedure
Create a playbook file, for example
~/playbook.yml
, with the following content:--- - hosts: managed-node-01.example.com roles: - rhel-system-roles.storage vars: storage_volumes: - name: barefs type: disk disks: - sdb fs_type: ext4 fs_label: label-name mount_point: /mnt/data
-
The playbook creates the file system on the
/dev/sdb
disk. -
The playbook persistently mounts the file system at the
/mnt/data
directory. -
The label of the file system is
label-name
.
-
The playbook creates the file system on the
Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.yml
Note that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook ~/playbook.yml
Additional resources
-
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file -
/usr/share/doc/rhel-system-roles/storage/
directory
2.6. Creating and mounting an Ext3 file system by using the storage
RHEL system role
The example Ansible playbook applies the storage
role to create and mount an Ext3 file system.
Prerequisites
- You have prepared the control node and the managed nodes
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudo
permissions on them.
Procedure
Create a playbook file, for example
~/playbook.yml
, with the following content:--- - hosts: all roles: - rhel-system-roles.storage vars: storage_volumes: - name: barefs type: disk disks: - sdb fs_type: ext3 fs_label: label-name mount_point: /mnt/data mount_user: somebody mount_group: somegroup mount_mode: 0755
-
The playbook creates the file system on the
/dev/sdb
disk. -
The playbook persistently mounts the file system at the
/mnt/data
directory. -
The label of the file system is
label-name
.
-
The playbook creates the file system on the
Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.yml
Note that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook ~/playbook.yml
Additional resources
-
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file -
/usr/share/doc/rhel-system-roles/storage/
directory
2.7. Creating a swap volume by using the storage
RHEL system role
This section provides an example Ansible playbook. This playbook applies the storage
role to create a swap volume, if it does not exist, or to modify the swap volume, if it already exist, on a block device by using the default parameters.
Prerequisites
- You have prepared the control node and the managed nodes
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudo
permissions on them.
Procedure
Create a playbook file, for example
~/playbook.yml
, with the following content:--- - name: Create a disk device with swap hosts: managed-node-01.example.com roles: - rhel-system-roles.storage vars: storage_volumes: - name: swap_fs type: disk disks: - /dev/sdb size: 15 GiB fs_type: swap
The volume name (
swap_fs
in the example) is currently arbitrary. Thestorage
role identifies the volume by the disk device listed under thedisks:
attribute.Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.yml
Note that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook ~/playbook.yml
Additional resources
-
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file -
/usr/share/doc/rhel-system-roles/storage/
directory
2.8. Configuring a RAID volume by using the storage
RHEL system role
With the storage
system role, you can configure a RAID volume on RHEL by using Red Hat Ansible Automation Platform and Ansible-Core. Create an Ansible playbook with the parameters to configure a RAID volume to suit your requirements.
Device names might change in certain circumstances, for example, when you add a new disk to a system. Therefore, to prevent data loss, use persistent naming attributes in the playbook. For more information about persistent naming attributes, see Overview of persistent naming attributes.
Prerequisites
- You have prepared the control node and the managed nodes
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudo
permissions on them.
Procedure
Create a playbook file, for example
~/playbook.yml
, with the following content:--- - name: Manage local storage hosts: managed-node-01.example.com tasks: - name: Create a RAID on sdd, sde, sdf, and sdg ansible.builtin.include_role: name: rhel-system-roles.storage vars: storage_safe_mode: false storage_volumes: - name: data type: raid disks: [sdd, sde, sdf, sdg] raid_level: raid0 raid_chunk_size: 32 KiB mount_point: /mnt/data state: present
For details about all variables used in the playbook, see the
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file on the control node.Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.yml
Note that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook ~/playbook.yml
Verification
Verify that the array was correctly created:
# ansible managed-node-01.example.com -m command -a 'mdadm --detail /dev/md/data'
Additional resources
-
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file -
/usr/share/doc/rhel-system-roles/storage/
directory - Managing RAID
2.9. Configuring an LVM pool with RAID by using the storage
RHEL system role
With the storage
system role, you can configure an LVM pool with RAID on RHEL by using Red Hat Ansible Automation Platform. You can set up an Ansible playbook with the available parameters to configure an LVM pool with RAID.
Prerequisites
- You have prepared the control node and the managed nodes
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudo
permissions on them.
Procedure
Create a playbook file, for example
~/playbook.yml
, with the following content:--- - name: Manage local storage hosts: managed-node-01.example.com tasks: - name: Configure LVM pool with RAID ansible.builtin.include_role: name: rhel-system-roles.storage vars: storage_safe_mode: false storage_pools: - name: my_pool type: lvm disks: [sdh, sdi] raid_level: raid1 volumes: - name: my_volume size: "1 GiB" mount_point: "/mnt/app/shared" fs_type: xfs state: present
For details about all variables used in the playbook, see the
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file on the control node.Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.yml
Note that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook ~/playbook.yml
Verification
Verify that your pool is on RAID:
# ansible managed-node-01.example.com -m command -a 'lsblk'
Additional resources
-
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file -
/usr/share/doc/rhel-system-roles/storage/
directory - Managing RAID
2.10. Configuring a stripe size for RAID LVM volumes by using the storage
RHEL system role
With the storage
system role, you can configure a stripe size for RAID LVM volumes on RHEL by using Red Hat Ansible Automation Platform. You can set up an Ansible playbook with the available parameters to configure an LVM pool with RAID.
Prerequisites
- You have prepared the control node and the managed nodes
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudo
permissions on them.
Procedure
Create a playbook file, for example
~/playbook.yml
, with the following content:--- - name: Manage local storage hosts: managed-node-01.example.com tasks: - name: Configure stripe size for RAID LVM volumes ansible.builtin.include_role: name: rhel-system-roles.storage vars: storage_safe_mode: false storage_pools: - name: my_pool type: lvm disks: [sdh, sdi] volumes: - name: my_volume size: "1 GiB" mount_point: "/mnt/app/shared" fs_type: xfs raid_level: raid0 raid_stripe_size: "256 KiB" state: present
For details about all variables used in the playbook, see the
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file on the control node.Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.yml
Note that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook ~/playbook.yml
Verification
Verify that stripe size is set to the required size:
# ansible managed-node-01.example.com -m command -a 'lvs -o+stripesize /dev/my_pool/my_volume'
Additional resources
-
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file -
/usr/share/doc/rhel-system-roles/storage/
directory - Managing RAID
2.11. Configuring an LVM-VDO volume by using the storage
RHEL system role
You can use the storage
RHEL system role to create a VDO volume on LVM (LVM-VDO) with enabled compression and deduplication.
Because of the storage
system role use of LVM-VDO, only one volume can be created per pool.
Prerequisites
- You have prepared the control node and the managed nodes
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudo
permissions on them.
Procedure
Create a playbook file, for example
~/playbook.yml
, with the following content:--- - name: Manage local storage hosts: managed-node-01.example.com tasks: - name: Create LVM-VDO volume under volume group 'myvg' ansible.builtin.include_role: name: rhel-system-roles.storage vars: storage_pools: - name: myvg disks: - /dev/sdb volumes: - name: mylv1 compression: true deduplication: true vdo_pool_size: 10 GiB size: 30 GiB mount_point: /mnt/app/shared
The settings specified in the example playbook include the following:
vdo_pool_size: <size>
- The actual size that the volume takes on the device. You can specify the size in human-readable format, such as 10 GiB. If you do not specify a unit, it defaults to bytes.
size: <size>
- The virtual size of VDO volume.
For details about all variables used in the playbook, see the
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file on the control node.Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.yml
Note that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook ~/playbook.yml
Verification
View the current status of compression and deduplication:
$ ansible managed-node-01.example.com -m command -a 'lvs -o+vdo_compression,vdo_compression_state,vdo_deduplication,vdo_index_state' LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert VDOCompression VDOCompressionState VDODeduplication VDOIndexState mylv1 myvg vwi-a-v--- 3.00t vpool0 enabled online enabled online
Additional resources
-
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file -
/usr/share/doc/rhel-system-roles/storage/
directory
2.12. Creating a LUKS2 encrypted volume by using the storage
RHEL system role
You can use the storage
role to create and configure a volume encrypted with LUKS by running an Ansible playbook.
Prerequisites
- You have prepared the control node and the managed nodes
- You are logged in to the control node as a user who can run playbooks on the managed nodes.
-
The account you use to connect to the managed nodes has
sudo
permissions on them.
Procedure
Store your sensitive variables in an encrypted file:
Create the vault:
$ ansible-vault create vault.yml New Vault password: <vault_password> Confirm New Vault password: <vault_password>
After the
ansible-vault create
command opens an editor, enter the sensitive data in the<key>: <value>
format:luks_password: <password>
- Save the changes, and close the editor. Ansible encrypts the data in the vault.
Create a playbook file, for example
~/playbook.yml
, with the following content:--- - name: Manage local storage hosts: managed-node-01.example.com vars_files: - vault.yml tasks: - name: Create and configure a volume encrypted with LUKS ansible.builtin.include_role: name: rhel-system-roles.storage vars: storage_volumes: - name: barefs type: disk disks: - sdb fs_type: xfs fs_label: <label> mount_point: /mnt/data encryption: true encryption_password: "{{ luks_password }}"
For details about all variables used in the playbook, see the
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file on the control node.Validate the playbook syntax:
$ ansible-playbook --ask-vault-pass --syntax-check ~/playbook.yml
Note that this command only validates the syntax and does not protect against a wrong but valid configuration.
Run the playbook:
$ ansible-playbook --ask-vault-pass ~/playbook.yml
Verification
Find the
luksUUID
value of the LUKS encrypted volume:# ansible managed-node-01.example.com -m command -a 'cryptsetup luksUUID /dev/sdb' 4e4e7970-1822-470e-b55a-e91efe5d0f5c
View the encryption status of the volume:
# ansible managed-node-01.example.com -m command -a 'cryptsetup status luks-4e4e7970-1822-470e-b55a-e91efe5d0f5c' /dev/mapper/luks-4e4e7970-1822-470e-b55a-e91efe5d0f5c is active and is in use. type: LUKS2 cipher: aes-xts-plain64 keysize: 512 bits key location: keyring device: /dev/sdb ...
Verify the created LUKS encrypted volume:
# ansible managed-node-01.example.com -m command -a 'cryptsetup luksDump /dev/sdb' LUKS header information Version: 2 Epoch: 3 Metadata area: 16384 [bytes] Keyslots area: 16744448 [bytes] UUID: 4e4e7970-1822-470e-b55a-e91efe5d0f5c Label: (no label) Subsystem: (no subsystem) Flags: (no flags) Data segments: 0: crypt offset: 16777216 [bytes] length: (whole device) cipher: aes-xts-plain64 sector: 512 [bytes] ...
Additional resources
-
/usr/share/ansible/roles/rhel-system-roles.storage/README.md
file -
/usr/share/doc/rhel-system-roles/storage/
directory - Encrypting block devices by using LUKS
- Ansible vault