ipam: Wire AllowFirstLastIPs option into cidrPool#45082
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Add an `allowFirstLastIPs` parameter to `cidrPool` that propagates the `WithAllowFirstLastIPs` option to `ipallocator.NewCIDRRange` when creating new CIDR allocators in `updatePool`. This allows pools used for delegated prefixes (e.g. AWS /28 prefix delegation) to allocate all IPs in the range without reserving the first and last addresses. Existing multi-pool callers pass false to preserve current behavior. Relates to [cilium/design-cfps#87](cilium/design-cfps#87) This is a direct followup to #45025 and a small setup step before the larger migration or ENI IPAM from the CRD allocator to the multipool allocator. Signed-off-by: Hadrien Patte <hadrien.patte@datadoghq.com>
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Replace the CRD allocator with the multi-pool allocator for ENI IPAM mode on the agent side. Previous PRs cilium#45110 and cilium#45124 ensure the operator already supports this new agent setup. The new `eniMultiPoolAllocator` is a light wrapper on the standard `multiPoolAllocator` that enriches `AllocationResult` with ENI-specific required metadata via `buildENIAllocationResult` (see cilium#45089). Key differences from the standard multi-pool allocator: * `AllowFirstLastIPs` is enabled so /28 prefix delegation ranges are fully allocatable (see cilium#45025 and cilium#45082). * `LinearPreAlloc` uses a simple `inUse + preAlloc` formula for demand computation instead of `neededIPCeil` rounding. This matches the CRD allocator's `calculateNeededIPs` semantics and is necessary to ensure the operator can recover the exact IP usage from the demand signal (requested - preAllocate) (see cilium#45124). * No dependency on `CiliumPodIPPool` CRDs, pools are managed by the operator via Spec.IPAM.Pools.Allocated (see cilium#45110). The agents now read CIDRs from `Spec.IPAM.Pools.Allocated`, allocate IPs locally, and write aggregate demand to `Spec.IPAM.Pools.Requested`. They no longer writes per-IP usage to `Status.IPAM.Used`, achieving a reduction of kubernetes API pressure. Relates to cilium/design-cfps#87 Signed-off-by: Hadrien Patte <hadrien.patte@datadoghq.com>
HadrienPatte
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Replace the CRD allocator with the multi-pool allocator for ENI IPAM mode on the agent side. Previous PRs cilium#45110 and cilium#45124 ensure the operator already supports this new agent setup. The new `eniMultiPoolAllocator` is a light wrapper on the standard `multiPoolAllocator` that enriches `AllocationResult` with ENI-specific required metadata via `buildENIAllocationResult` (see cilium#45089). Key differences from the standard multi-pool allocator: * `AllowFirstLastIPs` is enabled so /28 prefix delegation ranges are fully allocatable (see cilium#45025 and cilium#45082). * `LinearPreAlloc` uses a simple `inUse + preAlloc` formula for demand computation instead of `neededIPCeil` rounding. This matches the CRD allocator's `calculateNeededIPs` semantics and is necessary to ensure the operator can recover the exact IP usage from the demand signal (requested - preAllocate) (see cilium#45124). * No dependency on `CiliumPodIPPool` CRDs, pools are managed by the operator via Spec.IPAM.Pools.Allocated (see cilium#45110). The agents now read CIDRs from `Spec.IPAM.Pools.Allocated`, allocate IPs locally, and write aggregate demand to `Spec.IPAM.Pools.Requested`. They no longer writes per-IP usage to `Status.IPAM.Used`, achieving a reduction of kubernetes API pressure. Relates to cilium/design-cfps#87 Signed-off-by: Hadrien Patte <hadrien.patte@datadoghq.com>
HadrienPatte
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Apr 3, 2026
Replace the CRD allocator with the multi-pool allocator for ENI IPAM mode on the agent side. Previous PRs #45110 and #45124 ensure the operator already supports this new agent setup. The new `eniMultiPoolAllocator` is a light wrapper on the standard `multiPoolAllocator` that enriches `AllocationResult` with ENI-specific required metadata via `buildENIAllocationResult` (see #45089). Key differences from the standard multi-pool allocator: * `AllowFirstLastIPs` is enabled so /28 prefix delegation ranges are fully allocatable (see #45025 and #45082). * `LinearPreAlloc` uses a simple `inUse + preAlloc` formula for demand computation instead of `neededIPCeil` rounding. This matches the CRD allocator's `calculateNeededIPs` semantics and is necessary to ensure the operator can recover the exact IP usage from the demand signal (requested - preAllocate) (see #45124). * No dependency on `CiliumPodIPPool` CRDs, pools are managed by the operator via Spec.IPAM.Pools.Allocated (see #45110). The agents now read CIDRs from `Spec.IPAM.Pools.Allocated`, allocate IPs locally, and write aggregate demand to `Spec.IPAM.Pools.Requested`. They no longer writes per-IP usage to `Status.IPAM.Used`, achieving a reduction of kubernetes API pressure. Relates to cilium/design-cfps#87 Signed-off-by: Hadrien Patte <hadrien.patte@datadoghq.com>
HadrienPatte
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Apr 4, 2026
Replace the CRD allocator with the multi-pool allocator for ENI IPAM mode on the agent side. Previous PRs #45110 and #45124 ensure the operator already supports this new agent setup. The new `eniMultiPoolAllocator` is a light wrapper on the standard `multiPoolAllocator` that enriches `AllocationResult` with ENI-specific required metadata via `buildENIAllocationResult` (see #45089). Key differences from the standard multi-pool allocator: * `AllowFirstLastIPs` is enabled so /28 prefix delegation ranges are fully allocatable (see #45025 and #45082). * `LinearPreAlloc` uses a simple `inUse + preAlloc` formula for demand computation instead of `neededIPCeil` rounding. This matches the CRD allocator's `calculateNeededIPs` semantics and is necessary to ensure the operator can recover the exact IP usage from the demand signal (requested - preAllocate) (see #45124). * No dependency on `CiliumPodIPPool` CRDs, pools are managed by the operator via Spec.IPAM.Pools.Allocated (see #45110). The agents now read CIDRs from `Spec.IPAM.Pools.Allocated`, allocate IPs locally, and write aggregate demand to `Spec.IPAM.Pools.Requested`. They no longer writes per-IP usage to `Status.IPAM.Used`, achieving a reduction of kubernetes API pressure. Relates to cilium/design-cfps#87 Signed-off-by: Hadrien Patte <hadrien.patte@datadoghq.com>
HadrienPatte
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Apr 4, 2026
Replace the CRD allocator with the multi-pool allocator for ENI IPAM mode on the agent side. Previous PR #45124 ensures the operator already supports this new agent setup. The new `eniMultiPoolAllocator` is a light wrapper on the standard `multiPoolAllocator` that enriches `AllocationResult` with ENI-specific required metadata via `buildENIAllocationResult` (see #45089). Key differences from the standard multi-pool allocator: * `AllowFirstLastIPs` is enabled so /28 prefix delegation ranges are fully allocatable (see #45025 and #45082). * `LinearPreAlloc` uses a simple `inUse + preAlloc` formula for demand computation instead of `neededIPCeil` rounding. This matches the CRD allocator's `calculateNeededIPs` semantics and is necessary to ensure the operator can recover the exact IP usage from the demand signal (requested - preAllocate) (see #45124). * No dependency on `CiliumPodIPPool` CRDs, pools are instead populated by the agent from `Status.ENI.ENIs` which is maintained by the operator. The agents now read CIDRs from `Status.ENI.ENIs`, allocate IPs locally, and write aggregate demand to `Spec.IPAM.Pools.Requested`. They no longer writes per-IP usage to `Status.IPAM.Used`, achieving a reduction of kubernetes API pressure. Relates to cilium/design-cfps#87 Signed-off-by: Hadrien Patte <hadrien.patte@datadoghq.com>
HadrienPatte
added a commit
that referenced
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Apr 4, 2026
Replace the CRD allocator with the multi-pool allocator for ENI IPAM mode on the agent side. Previous PR #45124 ensures the operator already supports this new agent setup. The new `eniMultiPoolAllocator` is a light wrapper on the standard `multiPoolAllocator` that enriches `AllocationResult` with ENI-specific required metadata via `buildENIAllocationResult` (see #45089). Key differences from the standard multi-pool allocator: * `AllowFirstLastIPs` is enabled so /28 prefix delegation ranges are fully allocatable (see #45025 and #45082). * `LinearPreAlloc` uses a simple `inUse + preAlloc` formula for demand computation instead of `neededIPCeil` rounding. This matches the CRD allocator's `calculateNeededIPs` semantics and is necessary to ensure the operator can recover the exact IP usage from the demand signal (requested - preAllocate) (see #45124). * No dependency on `CiliumPodIPPool` CRDs, pools are instead populated by the agent from `Status.ENI.ENIs` which is maintained by the operator. The agents now read CIDRs from `Status.ENI.ENIs`, allocate IPs locally, and write aggregate demand to `Spec.IPAM.Pools.Requested`. They no longer writes per-IP usage to `Status.IPAM.Used`, achieving a reduction of kubernetes API pressure. Relates to cilium/design-cfps#87 Signed-off-by: Hadrien Patte <hadrien.patte@datadoghq.com>
HadrienPatte
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that referenced
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Apr 5, 2026
Replace the CRD allocator with the multi-pool allocator for ENI IPAM mode on the agent side. Previous PR #45124 ensures the operator already supports this new agent setup. The new `eniMultiPoolAllocator` is a light wrapper on the standard `multiPoolAllocator` that enriches `AllocationResult` with ENI-specific required metadata via `buildENIAllocationResult` (see #45089). Key differences from the standard multi-pool allocator: * `AllowFirstLastIPs` is enabled so /28 prefix delegation ranges are fully allocatable (see #45025 and #45082). * `LinearPreAlloc` uses a simple `inUse + preAlloc` formula for demand computation instead of `neededIPCeil` rounding. This matches the CRD allocator's `calculateNeededIPs` semantics and is necessary to ensure the operator can recover the exact IP usage from the demand signal (requested - preAllocate) (see #45124). * No dependency on `CiliumPodIPPool` CRDs, pools are instead populated by the agent from `Status.ENI.ENIs` which is maintained by the operator. The agents now read CIDRs from `Status.ENI.ENIs`, allocate IPs locally, and write aggregate demand to `Spec.IPAM.Pools.Requested`. They no longer writes per-IP usage to `Status.IPAM.Used`, achieving a reduction of kubernetes API pressure. Relates to cilium/design-cfps#87 Signed-off-by: Hadrien Patte <hadrien.patte@datadoghq.com>
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Add an
allowFirstLastIPsparameter tocidrPoolthat propagates theWithAllowFirstLastIPsoption toipallocator.NewCIDRRangewhen creating new CIDR allocators inupdatePool. This allows pools used for delegated prefixes (e.g. AWS /28 prefix delegation) to allocate all IPs in the range without reserving the first and last addresses.Existing multi-pool callers pass false to preserve current behavior.
Relates to cilium/design-cfps#87
This is a direct followup to #45025 and a small setup step before the larger migration or ENI IPAM from the CRD allocator to the multipool allocator.