25.9. 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
sudopermissions for these nodes.
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: redhat.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/sharedThe 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.mdfile on the control node.Validate the playbook syntax:
$ ansible-playbook --syntax-check ~/playbook.ymlNote 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