Chapter 2. Managing local storage by using the RHEL system role

Procedure

1. 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. The storage role identifies the volume by the disk device listed under the disks: 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 Managing logical volumes by using the storage RHEL system role.

     Do not provide the path to the LV device.

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Procedure

1. 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.

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Procedure

1. 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_pools:
         - name: myvg
           disks:
             - sda
             - sdb
             - sdc
           volumes:
             - name: mylv
               size: 2G
               fs_type: ext4
               mount_point: /mnt/dat

   • The myvg volume group consists of the following disks: /dev/sda, /dev/sdb, and /dev/sdc.
   • If the myvg volume group already exists, the playbook adds the logical volume to the volume group.
   • If the myvg volume group does not exist, the playbook creates it.
   • The playbook creates an Ext4 file system on the mylv logical volume, and persistently mounts the file system at /mnt.

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Procedure

1. 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_options: discard

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Procedure

1. 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.

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Procedure

1. 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.

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Procedure

1. Create a playbook file, for example ~/playbook.yml, with the following content:

   ---
   - name: Create LVM pool over three disks
     hosts: managed-node-01.example.com
     tasks:
       - name: Resize LVM logical volume with file system
         ansible.builtin.include_role:
           name: rhel-system-roles.storage
         vars:
           storage_pools:
             - name: myvg
               disks:
                 - /dev/sda
                 - /dev/sdb
                 - /dev/sdc
               volumes:
                 - name: mylv1
                   size: 10 GiB
                   fs_type: ext4
                   mount_point: /opt/mount1
                 - name: mylv2
                   size: 50 GiB
                   fs_type: ext4
                   mount_point: /opt/mount2

   This playbook resizes the following existing file systems:

   • The Ext4 file system on the mylv1 volume, which is mounted at /opt/mount1, resizes to 10 GiB.
   • The Ext4 file system on the mylv2 volume, which is mounted at /opt/mount2, resizes to 50 GiB.

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Procedure

1. 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. The storage role identifies the volume by the disk device listed under the disks: attribute.

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Procedure

1. Create a playbook file, for example ~/playbook.yml, with the following content:

   ---
   - name: Configure the 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

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Procedure

1. Create a playbook file, for example ~/playbook.yml, with the following content:

   ---
   - name: Configure LVM pool with RAID
     hosts: managed-node-01.example.com
     roles:
       - 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

   To create an LVM pool with RAID, you must specify the RAID type by using the raid_level parameter.

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Procedure

1. Create a playbook file, for example ~/playbook.yml, with the following content:

   ---
   - name: Configure stripe size for RAID LVM volumes
     hosts: managed-node-01.example.com
     roles:
       - 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: raid1
               raid_stripe_size: "256 KiB"
               state: present

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Procedure

1. Create a playbook file, for example ~/playbook.yml, with the following content:

   - name: Create LVM VDO volume under volume group 'myvg'
     hosts: managed-node-01.example.com
     roles:
       - 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

   In this example, the compression and deduplication pools are set to true, which specifies that the VDO is used. The following describes the usage of these parameters:

   • The deduplication is used to deduplicate the duplicated data stored on the storage volume.
   • The compression is used to compress the data stored on the storage volume, which results in more storage capacity.
   • The vdo_pool_size specifies the actual size the volume takes on the device. The virtual size of VDO volume is set by the size parameter.

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Procedure

1. Create a playbook file, for example ~/playbook.yml, with the following content:

   ---
   - name: Create and configure a volume encrypted with LUKS
     hosts: managed-node-01.example.com
     roles:
       - rhel-system-roles.storage
     vars:
       storage_volumes:
         - name: barefs
           type: disk
           disks:
            - sdb
           fs_type: xfs
           fs_label: label-name
           mount_point: /mnt/data
           encryption: true
           encryption_password: <password>

   You can also add other encryption parameters, such as encryption_key, encryption_cipher, encryption_key_size, and encryption_luks, to the playbook file.

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml

Verification

1. View the encryption status:

   # cryptsetup status sdb
   
   /dev/mapper/sdb is active and is in use.
   type: LUKS2
   cipher: aes-xts-plain64
   keysize: 512 bits
   key location: keyring
   device: /dev/sdb
   ...

2. Verify the created LUKS encrypted volume:

   # cryptsetup luksDump /dev/sdb
   
   Version:        2
   Epoch:          6
   Metadata area:  16384 [bytes]
   Keyslots area:  33521664 [bytes]
   UUID:           a4c6be82-7347-4a91-a8ad-9479b72c9426
   Label:          (no label)
   Subsystem:      (no subsystem)
   Flags:          allow-discards
   
   Data segments:
     0: crypt
           offset: 33554432 [bytes]
           length: (whole device)
           cipher: aes-xts-plain64
           sector: 4096 [bytes]
   ...

Procedure

1. Create a playbook file, for example ~/playbook.yml, with the following content:

   ---
   - name: Express volume sizes as a percentage of the pool's total size
     hosts: managed-node-01.example.com
     roles:
       - rhel-system-roles.storage
     vars:
       storage_pools:
         - name: myvg
           disks:
             - /dev/sdb
           volumes:
             - name: data
               size: 60%
               mount_point: /opt/mount/data
             - name: web
               size: 30%
               mount_point: /opt/mount/web
             - name: cache
               size: 10%
               mount_point: /opt/cache/mount

   This example specifies the size of LVM volumes as a percentage of the pool size, for example: 60%. Alternatively, you can also specify the size of LVM volumes as a percentage of the pool size in a human-readable size of the file system, for example, 10g or 50 GiB.

2. 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.

3. Run the playbook:

   $ ansible-playbook ~/playbook.yml