Placement groups control how Virtual Machines are distributed across physical hosts — co-locate VMs for low-latency communication or spread them across hosts for fault tolerance.
## Create a placement groupThe policy selected at creation is permanent — it cannot be changed afterwards. Choose Affinity to co-locate VMs on the same host, Anti-Affinity to spread them across different hosts, or Soft Anti-Affinity to prefer separation while allowing sharing when resources are limited.
1. In the [Gcore Customer Portal](https://portal.gcore.com), navigate to **Cloud** and select the target region. 2. In the left sidebar, open **Virtual Instances** and select **Placement Groups**. 3. Click **Create Placement Group**. 4. Enter a **Name** for the group. 5. Select a **Policy** — **Affinity**, **Anti-Affinity**, or **Soft Anti-Affinity**. 6. In the dialog, click **Create**.
## Create a Virtual Machine in a placement group
Assign a VM to a placement group during instance creation by selecting the group in the **Additional options** section.
1. In the left sidebar, open **Virtual Instances** and click **Create Instance**. 2. Configure the Virtual Instance as described in [Create](/cloud/virtual-instances/create-an-instance). 3. In the **Additional options** section, select the **Add to placement group** checkbox. 4. Select an existing group from the **Placement Group** dropdown, or click **Add placement group** to create one. 5. Complete the remaining configuration and click **Create Instance**.
## Add an existing Virtual Machine to a group
The Virtual Machine must already exist in the same region as the placement group.
1. In the left sidebar, open **Virtual Instances** and select the target instance. 2. Open the **Placement Group** tab. 3. Select a group from the **Placement Group** dropdown, or click **Add placement group** to create one. 4. Click **Add**. 5. In the confirmation dialog, click **Yes, add**. ## Move a Virtual Machine between groupsMoving a VM between groups requires two operations: first remove it from the current group, then assign it to the new one. Between the two steps the VM has no placement constraint.
1. In the left sidebar, open **Virtual Instances** and select the target instance. 2. Open the **Placement Group** tab. 3. Click **Remove**.
4. In the confirmation dialog, click **Yes, remove**.
5. Select the new group from the **Placement Group** dropdown.
6. Click **Add**.
7. In the confirmation dialog, click **Yes, add**.
Placement groups control how VMs are distributed across physical hosts — grouping them together for low-latency communication or spreading them apart for fault tolerance.
Set environment variables before running any of the examples below:
```bash theme={null} export GCORE_API_KEY="{YOUR_API_KEY}" export GCORE_CLOUD_PROJECT_ID="{YOUR_PROJECT_ID}" export GCORE_CLOUD_REGION_ID="{YOUR_REGION_ID}" export IMAGE_ID="{YOUR_IMAGE_ID}" export FLAVOR_ID="{YOUR_FLAVOR_ID}" ```The scripts below create an anti-affinity placement group, launch a VM in it, verify membership, then remove the VM and delete the group.
GET /cloud/v1/flavors/{project_id}/{region_id}. |
| `image_id` | Yes | Public image ID — region-specific; list available images via GET /cloud/v1/images/{project_id}/{region_id}?visibility=public. |
GET /cloud/v1/tasks/{task_id} every 5 seconds until `state` is `FINISHED`. The instance ID is in `created_resources.instances[0]`.
Export the instance ID:
```bash theme={null}
export INSTANCE_ID="{instance_id from created_resources}"
```
GET /cloud/v1/tasks/{task_id} every 5 seconds until `state` is `FINISHED`.
GET /cloud/v1/tasks/{task_id} every 5 seconds until `state` is `FINISHED`.
GET /cloud/v1/tasks/{task_id} until each `state` is `FINISHED`.
Deleting a placement group does not delete the VMs in it — the VMs keep running without a placement constraint.
GET /cloud/v1/tasks/{task_id} every 5 seconds until `state` is `FINISHED`.
Group Virtual Machines by scheduling policy — `affinity` to co-locate, `anti-affinity` to spread across hosts. The [`gcore_cloud_placement_group`](https://registry.terraform.io/providers/G-Core/gcore/latest/docs/resources/cloud_placement_group) resource manages the group and its membership.
## Create a placement groupDeclares a placement group with the selected policy. Choose `affinity` to co-locate VMs on the same host, `anti-affinity` to spread them across different hosts, or `soft-anti-affinity` to prefer separation but allow sharing when resources are constrained.
```hcl theme={null} resource "gcore_cloud_placement_group" "example" { project_id = var.project_id region_id = var.region_id name = "my-group" policy = "anti-affinity" } output "group_id" { value = gcore_cloud_placement_group.example.id } ```Set the `instances` attribute to a list of VM IDs. Terraform manages the full membership declaratively — adding an entry assigns the VM to the group, removing an entry removes it.
```hcl theme={null} resource "gcore_cloud_placement_group" "example" { project_id = var.project_id region_id = var.region_id name = "my-group" policy = "anti-affinity" instances = [ { instance_id = var.instance_id }, ] } ```To assign a VM to a group at creation time, set `servergroup_id = gcore_cloud_placement_group.example.id` in the [Virtual Machine](/cloud/virtual-instances/create-an-instance) resource instead.
## Delete a placement groupRemove the resource block — Terraform detects the missing declaration and deletes the group on the next `terraform apply`. VMs keep running; the placement constraint no longer applies.
```hcl theme={null} # Remove or comment out this block: # resource "gcore_cloud_placement_group" "example" { # name = "my-group" # policy = "anti-affinity" # project_id = var.project_id # region_id = var.region_id # } ``` ```bash theme={null} terraform apply ``` ## Import a placement groupUse when a placement group was created outside Terraform and needs to be managed as code.
```hcl theme={null} resource "gcore_cloud_placement_group" "example" { project_id = var.project_id region_id = var.region_id name = "my-group" policy = "anti-affinity" } ``` ```bash theme={null} terraform import gcore_cloud_placement_group.example '