Considerations for using blade servers

With the local storage (Virtuozzo Storage) as the default storage for compute volumes, we recommend using blade servers for Virtuozzo Hybrid Infrastructure installations if the blade configuration meets the general server requirements. Note that the local storage requires three or more SSD/HDD drives per server and a 10+ Gbit/s network between storage servers. Blade servers, however, usually support only up to two drives. With the recommended system disk configuration when two SSD drives are combined in a software RAID mirror, no drives will be left for the local storage.

You can also use blade servers with the supported external storage, for example, Pure Storage or NFS, as the main storage for compute volumes. In this case, you need to ensure that network performance is good enough to work with the local and external storage, with at least 10 Gbit/s speed between blades participating in the storage cluster. Even with external storage, Virtuozzo Storage is a mandatory component for storing VM templates and some system components with the default storage policy.

Consider the following three main use cases:

• Use case 1. Virtuozzo Hybrid Infrastructure with the local storage as the main storage based on blade servers with only two drives. This configuration is not recommended and cannot be used.
• Use case 2. Virtuozzo Hybrid Infrastructure with the local storage as the main storage based on storage blades or with at least three internal drives. This configuration is not recommended due to the limited number of storage options, but can be used. Some vendors support a special "storage blade" that can be attached to a "compute blade" and used as a disk chassis for additional 8-12 drives. In this case, there is enough storage to build software-defined storage (SDS) based on the blade storage only, without external storage.
• Use case 3. Virtuozzo Hybrid Infrastructure with external storage, for example, Pure Storage or NFS, as the main storage. Blade servers can be used as any other servers. All compute volumes should be stored on the external storage. You can sacrifice system reliability and use only one drive for the system, without RAID1, and the second drive as a storage disk for the default storage policy. Though this configuration is possible, it is not recommended as the loss of the single system disk will result in losing the entire node.