Quantity of servers
One of the strongest features of Virtuozzo Hybrid Infrastructure is scalability. The bigger the cluster, the better Virtuozzo Hybrid Infrastructure performs.
To achieve the best performance, keep at least 20 percent of the cluster capacity free.
One server
Even though three nodes are recommended even for the minimum configuration, you can start evaluating Virtuozzo Hybrid Infrastructure with just one node and add more nodes later. If you only want to use the Backup Gateway, you can deploy a very basic installation on a single virtual or physical node. Although in this case you may need to provide data redundancy by other means or risk losing user data.
At the very least, a storage cluster must have one metadata service and one chunk service running. You can do the following:
- Use a virtual machine (VM) with at least two virtual HDDs (three are recommended). In this case, only one HDD will be used for data storage and you may need to make sure that the VM is made redundant by the virtualization solution it runs on.
- Use a physical server with at least two disks (three are recommended). Have in mind that you will need to use more disks for storage to enable data redundancy. For more details on how to plan your server configuration, refer to Server requirements.
A single-node installation will let you evaluate such services as Backup Gateway and others. Refer to Backup storage requirements for more information on the required hardware. However, such a configuration will have two key limitations:
-
Just one MDS will be a single point of failure. If it fails, the entire cluster will stop working.
-
Just one CS will be able to store just one chunk replica. If it fails, the data will be lost.
Three to five servers
Three servers are required to test all of the product features.
The minimum configuration described in this table will let you evaluate the features of the storage cluster. It is not meant for production.
| Node # | 1st disk role | 2nd disk role | 3rd+ disk roles | Access points |
|---|---|---|---|---|
| 1 | System | Metadata | Storage | iSCSI, S3 private, S3 public, NFS, Backup Gateway |
| 2 | System | Metadata | Storage | iSCSI, S3 private, S3 public, NFS, Backup Gateway |
| 3 | System | Metadata | Storage | iSCSI, S3 private, S3 public, NFS, Backup Gateway |
| 3 nodes in total | 3 MDSs in total | 3+ CSs in total | Access point services run on three nodes in total. |
SSD disks can be assigned System, Metadata, and Cache roles at the same time, freeing up more disks for the storage role.
Five and more servers
For a production environment, at least five nodes are required to ensure that the cluster can survive failure of two nodes without data loss. For improved resilience, performance, and fault tolerance it is recommended to create production clusters from at least ten nodes.
A production-ready cluster can be created from just five nodes by using the recommended hardware. However, it is recommended to enter production with at least ten nodes if you are aiming to achieve significant performance advantages over direct-attached storage (DAS) or improved recovery times.
It is recommended to have at least five metadata services to ensure that the cluster can survive simultaneous failure of two nodes without data loss. The following configuration will help you create clusters for production environments:
| Node # | 1st disk role | 2nd disk role | 3rd+ disk roles | Access points |
|---|---|---|---|---|
| Nodes 1 to 5 | System | SSD; metadata, cache | Storage | iSCSI, S3 private, S3 public, Backup Gateway |
| Nodes 6+ | System | SSD; cache | Storage | iSCSI, S3 private, Backup Gateway |
| 5+ nodes in total | 5 MDSs in total | 5+ CSs in total | All nodes run required access points. |
See also