Placement Groups
You can add a cloud server to a placement group. Servers in a group can be located on different physical hosts, which increases infrastructure fault tolerance.
A placement group is created for a specific pool. Note that cloud servers in a group can be located in different segments within the pool.
You can work with placement groups in the control panel, using OpenStack CLI or Terraform.
Placement policy
When creating a group, you can select a group policy — it determines how servers will be placed on physical hardware:
- preferably on different hosts (soft-anti-affinity) — the system will strive to place servers on different hosts. If there is no suitable host available when creating a server, it will be created on the same host;
- strictly on different hosts (anti-affinity) — servers in a group are always located on different hosts. If we do not find a suitable host, the server will not be created.
Restrictions
A group can only be created for a single pool.
In one project, you can create no more than 100 placement groups.
A single group can contain no more than 15 cloud servers at a time.
You can add a cloud server to a placement group only when creating a cloud server.
Pricing
Creating a placement group is free of charge.
Only cloud servers included in the group and other cloud platform resources are charged according to the cloud platform payment model.