KEP-1880 MultiCIDRServiceAllocator

Signed-off-by: Antonio Ojea <[email protected]>

Author: aojea

content/en/docs/concepts/services-networking/service.md

@@ -1424,6 +1424,12 @@ Services with static IPs assigned with a very low risk of running into conflicts
 
 ### Service IP addresses {#ips-and-vips}
 
+{{< feature-state for_k8s_version="v1.27" state="alpha" >}}
+If you enable the `MultiCIDRServiceAllocator`
+[feature gate](/docs/reference/command-line-tools-reference/feature-gates/),
+the `ClusterIP` address associated to each server will have its own cluster
+representation as an `IPAddress` object.
+
 Unlike Pod IP addresses, which actually route to a fixed destination,
 Service IPs are not actually answered by a single host.  Instead, kube-proxy
 uses iptables (packet processing logic in Linux) to define _virtual_ IP addresses

content/en/docs/reference/command-line-tools-reference/feature-gates.md

@@ -150,6 +150,7 @@ For a reference to old feature gates that are removed, please refer to
 | `MixedProtocolLBService` | `false` | Alpha | 1.20 | 1.23 |
 | `MixedProtocolLBService` | `true` | Beta | 1.24 | |
 | `MultiCIDRRangeAllocator` | `false` | Alpha | 1.25 | |
+| `MultiCIDRServiceAllocator` | `false` | Alpha | 1.27 | |
 | `NetworkPolicyStatus` | `false` | Alpha | 1.24 |  |
 | `NodeInclusionPolicyInPodTopologySpread` | `false` | Alpha | 1.25 | |
 | `NodeOutOfServiceVolumeDetach` | `false` | Alpha | 1.24 | |
@@ -624,6 +625,8 @@ Each feature gate is designed for enabling/disabling a specific feature:
 - `MixedProtocolLBService`: Enable using different protocols in the same `LoadBalancer` type
   Service instance.
 - `MultiCIDRRangeAllocator`: Enables the MultiCIDR range allocator.
+- `MultiCIDRServiceAllocator`: Enables a new IPAddress object kind, and a new Service ClusterIP allocator.
+  The new allocator removes previous Service CIDR block size limitations for IPv4, and limits IPv6 size to a /64.
 - `NetworkPolicyEndPort`: Enable use of the field `endPort` in NetworkPolicy objects,
   allowing the selection of a port range instead of a single port.
 - `NetworkPolicyStatus`: Enable the `status` subresource for NetworkPolicy objects.