Libro sobre Proxmox maestria
Chapter 3
In an enterprise environment, storage space should be added seamlessly without shutting down critical nodes or virtual machines. By using a shared storage system, virtual machines can now go beyond one node to scattered multiple nodes spanned across regions. Shared storage such as distributed filesystem (for example, Ceph) can span across several racks and comprise well over several petabytes of usable storage space. Simply add a new node with a full bay of drives and tell the storage cluster to recognize the new node to increase storage space for the entire cluster. Since shared storage is separated from the virtual machine host nodes, storage can be increased or decreased without disturbing any running virtual machines. Later in the book, we will see how the Ceph-distributed filesystem can be expanded as much as your budget or needs allow you to.
Shared storage makes centralized backup possible by allowing each virtual machine host node to create a backup on one central location. This helps a backup manager or an administrator to implement a solid backup plan and manage the existing backups. Since a Proxmox node failure will not take the shared storage system down, virtual machines can be easily restored to a new node to reduce downtime.
Always use a separate node for backup purposes. It is not a good practice to store both virtual machines and their backups on the same node.
Data tiering is a concept where different files can be stored on different storage pools based on their performance requirement. For example, a virtual file server can provide very fast service if this VM is stored on an SSD storage pool, while a virtual backup server can be stored on a slower HDD storage since backup files are not frequently accessed, and thus, do not require very fast I/O. Tiering can be set up using different shared storage nodes with different performance levels. It can also be set up on the same node by assigning volumes or pools to specific sets of drives.