---
title: "Block affinity"
description: "Reference for the BlockAffinity resource in Calico Enterprise that records which node owns each IP address management block."
product: "Calico Enterprise"
version: "3.23 (latest)"
section: "Reference"
canonical_url: "https://docs.tigera.io/calico-enterprise/latest/reference/resources/blockaffinity"
---

# Block affinity

A block affinity resource (`BlockAffinity`) represents the affinity for an IPAM block. These are managed by Calico IPAM.

## Block affinity definition

### Metadata

| Field | Description                                                        | Accepted Values                                     | Schema |
| ----- | ------------------------------------------------------------------ | --------------------------------------------------- | ------ |
| name  | Unique name to describe this resource instance. Must be specified. | Alphanumeric string with optional `.`, `_`, or `-`. | string |

### Spec

| Field   | Description                                                                | Accepted Values                     | Schema  | Default |
| ------- | -------------------------------------------------------------------------- | ----------------------------------- | ------- | ------- |
| state   | State of the affinity with regard to any referenced IPAM blocks.           | confirmed, pending, pendingDeletion | string  |         |
| node    | The node that this affinity is assigned to.                                | The hostname of the node            | string  |         |
| cidr    | The CIDR range this block affinity references.                             | A valid IPv4 or IPv6 CIDR.          | string  |         |
| deleted | When set to true, clients should treat this block as if it does not exist. | true, false                         | boolean | `false` |

## Supported operations

| Datastore type        | Create | Delete | Update | Get/List | Watch |
| --------------------- | ------ | ------ | ------ | -------- | ----- |
| etcdv3                | No     | No     | No     | Yes      | Yes   |
| Kubernetes API server | No     | No     | No     | Yes      | Yes   |