Non-replicated disk placement groups
When creating non-replicated disks, resources are automatically distributed across the Yandex Cloud physical infrastructure. Your disks might get hosted on the same physical media. To make multiple disk failures less likely, you can combine your disks into placement groups.
Disks are not replicated on the Yandex Cloud side, but a user can make a disk replicated using placement groups.
Non-replicated disk placement group is a group of non-replicated disks where disks are hosted on different racks within the same availability zone. If one server rack that hosts disks from your group fails, this would affect only one disk.
Grouping of non-replicated disks reduces the risk of their parallel failure. However, the placement requirements are more demanding, so a physical resource shortage is more likely for non-replicated disks in a placement group rather than for the same number of ungrouped disks. You might fail to create a non-replicated disk in a placement group, but succeed to create it outside the group without any problem.
For more information about the organizational and technical limits of placement groups, see Quotas and limits in Compute Cloud.