Cloud Server network volumes
Network volumes are scalable block devices that can be easily transferred between cloud servers. They are suitable for scaling server disk space without changing the boot disk. Triple replication of disk volumes ensures high data integrity.
A network volume can be created along with a cloud server or created separately, and then you can create a server from it or connect it to a server as an additional disk.
You can work with network volumes in the control panel, using OpenStack CLI or Terraform.
You can track metrics for cloud server network volumes using the Metrics service.
Records of operations with network volumes are saved in audit logs.
Features of network volumes
- six network volume types with different recommended size limits, throughput values, and IOPS limits are available;
- can be used as a boot (system) disk for a cloud server or connected as an additional disk;
- you can connect up to 255 network volumes to a single cloud server if you use a standard disk with the virtio-scsi property (up to 4 if using ide, up to 26 if using virtio-blk);
- a network volume can be disconnected from a server;
- you can increase the network volume;
- from a network volume you can create an image, snapshot or another disk, set up backups;
- you can transfer a disk between pool segments, projects, and accounts.
Types of network volumes
- HDD Basic — HDD based on enterprise-class SATA disks. Suitable for storing large amounts of data that do not need to be frequently read or overwritten;
- SSD Basic — SSD for tasks that do not require high read and write speeds. Throughput and IOPS are higher than those of the basic HDD;
- SSD Universal — SSD, suitable for use as a cloud server boot disk;
- SSD Universal v2 — SSD with the ability to change the IOPS limit and without fixed separation of read and write operations. Suitable for tasks with uneven load. When choosing the maximum number of IOPS, it is suitable for CRM systems, monitoring systems, and for working with big data;
- SSD Fast — SSD NVMe with lower latency and higher performance compared to other types. Suitable for workloads requiring high read and write speeds.
- SSD Fast v2 — SSD NVMe with the ability to change the IOPS limit and without fixed separation of read and write operations. Suitable for tasks requiring high I/O speeds and a level of fault tolerance.
Disk types differ in recommended size limits, throughput values, and the number of read and write operations. See the Network volume limits table for details.
Different disk types are available in different pool segments. You can view type availability in locations in the Cloud Platform network volumes subsection of the Product availability in locations instructions.
You can view the list of IDs and type names in the Network volume type list subsection.
Network volume limits
The maximum size of boot and additional network volumes, throughput values, and the number of IOPS depend on the disk type.
Disks of the same type in different pool segments may have different limits. For example, if two network volumes with the SSD Universal type are in different segments (the first disk in ru-1c, the second in ru-8a), their limits will differ.
You can test disk performance.
What affects performance
Different disk types have different IOPS values—the number of read and write operations per second. Creating and checking the file system are procedures that require a certain number of read and write operations to the disk. The higher the performance of the disk, the faster these operations are completed.
When a cloud server starts for the first time, the file system on the system disk expands to the size of the disk. The larger the disk size and the lower its IOPS limits, the longer this process will take, and consequently, the longer it will take for the cloud server to start.
The file system size affects the state check time in the event of an abnormal server shutdown. Checking is enabled by default for boot (system) disks of all servers that are created from pre-made images.
List of network volume types
To create network volumes using OpenStack CLI and Terraform, IDs or names of network volume types are used. IDs and names differ in pool segments.
For example, 94350392-3e5c-4b5a-8a51-873f02af833b is the ID, and basicssd.ru-9a is the name for creating a network volume with the SSD Basic type in the ru-9a pool segment.
You can view the list of network volume types in all pool segments in a table or view the list of network volume types in a specific pool using OpenStack CLI.
List of network volume types in all pool segments
- St. Petersburg
- Moscow
- Novosibirsk
- Tashkent
- Almaty
- Nairobi
- ru-3
- ru-1
- ru-9
- gis-2
Where:
ID— network volume type ID;Имя— network volume type name and pool segment in theтип.сегмент_пулаformat, for examplebasic.ru-9a. Available types:basic— Basic HDD type;basicssd— Basic SSD type;universal— Universal SSD type;universal2— Universal SSD v2 type;fast— Fast SSD type;fast2— Fast SSD v2 type.
View the list of network volume types in a specific pool
-
View the list of types:
openstack volume type listExample response for the ru-9 pool:
+--------------------------------------+-----------------+| ID | Name |+--------------------------------------+-----------------+| 8ab097f3-3ffc-4fc4-9771-01fd512936eb | basic.ru-9a || 94350392-3e5c-4b5a-8a51-873f02af833b | basicssd.ru-9a || 52666f65-ec91-4c09-ad7e-207d10553e4a | universal.ru-9a || 2eab725b-4797-4c34-9e1b-4ad083629608 | universal2.ru-9a|| a67bd670-633b-4c82-bb91-84058140aa05 | fast.ru-9a |+--------------------------------------+-----------------+Where:
ID— network volume type ID;Name— network volume type name and pool segment in theтип.сегмент_пулаformat, for examplebasic.ru-9a. Available types:basic— Basic HDD type;basicssd— Basic SSD type;universal— Universal SSD type;universal2— Universal SSD v2 type;fast— Fast SSD type.
Cost
Network volumes are paid for using the Cloud Platform payment model.
Each GB of network volumes is charged. The cost depends on the network volume type, size, and the pool segment where it is located.
You can check the network volume size in the Control Panel: in the top menu, click Products → Cloud Servers → Disks section → disk row → Size.
For Universal SSD v2 and Fast SSD v2 network volumes, the number of IOPS used is also charged. The maximum number of IOPS per hour is taken into account. For Universal SSD v2, the first 2,000 IOPS are free of charge, and for Fast SSD v2 — the first 25,000 IOPS. You can view the number of IOPS in the Control Panel: in the top menu, click Products → Cloud Servers → Disks section → disk page → Settings.
The cost of one GB (for all network volume types) and one IOPS (for Universal SSD v2 and Fast SSD v2 disks) can be viewed on selectel.ru.