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Add tip: set --allocate-node-cidrs=false with Calico IPAM #2589

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ctauchen merged 1 commit into from
Mar 12, 2026
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Add tip: set --allocate-node-cidrs=false with Calico IPAM #2589

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10 changes: 10 additions & 0 deletions calico-cloud/networking/ipam/get-started-ip-addresses.mdx
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Expand Up @@ -24,6 +24,16 @@ The **calico-ipam** plugin uses $[prodname]’s IP pool resource to control how

By default, $[prodname] uses a single IP pool for the entire Kubernetes pod CIDR, but you can divide the pod CIDR into several pools. You can assign separate IP pools to particular selections of **nodes**, or to teams, users, or applications within a cluster using **namespaces**.

:::tip

Because Calico IPAM does not use the Kubernetes node CIDR allocations (`Node.spec.podCIDR`), you can set `--allocate-node-cidrs=false` on the kube-controller-manager.
This prevents Kubernetes from allocating unused node CIDRs and avoids `CIDRNotAvailable` events on nodes.

If you bootstrapped your cluster with kubeadm and passed `--pod-network-cidr`, kubeadm enables node CIDR allocation automatically.
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@caseydavenport caseydavenport Mar 12, 2026

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Might want to rephrase this - it sort of implies that you shouldn't pass pod-network-cidr, but that argument is useful for other reasons.

See the [Kubernetes documentation](https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-reconfigure/) for instructions on reconfiguring the controller manager after cluster creation.
Comment on lines +29 to +33
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Copilot AI Mar 12, 2026

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The new tip says Calico IPAM doesn’t use Node.spec.podCIDR, but later this page documents host-local IPAM using Node.Spec.PodCIDR. To avoid readers thinking the tip applies to host-local (or Calico generally), please scope it explicitly to the calico-ipam plugin and use consistent Node field notation (and optionally mention podCIDRs for dual-stack).

Copilot uses AI. Check for mistakes.

:::

You can control which pools $[prodname] uses for each pod using

- node selectors
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10 changes: 10 additions & 0 deletions ...-cloud_versioned_docs/version-22-2/networking/ipam/get-started-ip-addresses.mdx
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Expand Up @@ -24,6 +24,16 @@ The **calico-ipam** plugin uses $[prodname]’s IP pool resource to control how

By default, $[prodname] uses a single IP pool for the entire Kubernetes pod CIDR, but you can divide the pod CIDR into several pools. You can assign separate IP pools to particular selections of **nodes**, or to teams, users, or applications within a cluster using **namespaces**.

:::tip

Because Calico IPAM does not use the Kubernetes node CIDR allocations (`Node.spec.podCIDR`), you can set `--allocate-node-cidrs=false` on the kube-controller-manager.
This prevents Kubernetes from allocating unused node CIDRs and avoids `CIDRNotAvailable` events on nodes.

If you bootstrapped your cluster with kubeadm and passed `--pod-network-cidr`, kubeadm enables node CIDR allocation automatically.
See the [Kubernetes documentation](https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-reconfigure/) for instructions on reconfiguring the controller manager after cluster creation.
Comment on lines +29 to +33
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Copilot AI Mar 12, 2026

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This new tip references Node.spec.podCIDR and is phrased as “Calico IPAM”, but later the page states host-local IPAM uses Node.Spec.PodCIDR. Please reword the tip to explicitly apply only to the calico-ipam plugin and align the Node field notation/capitalization (and optionally mention podCIDRs for dual-stack).

Copilot uses AI. Check for mistakes.

:::

You can control which pools $[prodname] uses for each pod using

- node selectors
Expand Down
10 changes: 10 additions & 0 deletions calico-enterprise/networking/ipam/get-started-ip-addresses.mdx
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Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,16 @@ The **calico-ipam** plugin uses $[prodname]’s IP pool resource to control how

By default, $[prodname] uses a single IP pool for the entire Kubernetes pod CIDR, but you can divide the pod CIDR into several pools. You can assign separate IP pools to particular selections of **nodes**, or to teams, users, or applications within a cluster using **namespaces**.

:::tip

Because Calico IPAM does not use the Kubernetes node CIDR allocations (`Node.spec.podCIDR`), you can set `--allocate-node-cidrs=false` on the kube-controller-manager.
This prevents Kubernetes from allocating unused node CIDRs and avoids `CIDRNotAvailable` events on nodes.

If you bootstrapped your cluster with kubeadm and passed `--pod-network-cidr`, kubeadm enables node CIDR allocation automatically.
See the [Kubernetes documentation](https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-reconfigure/) for instructions on reconfiguring the controller manager after cluster creation.
Comment on lines +29 to +33
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Copilot AI Mar 12, 2026

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This tip is phrased as “Calico IPAM” and references Node.spec.podCIDR, but later the host-local section calls out Node.Spec.PodCIDR as being used. To avoid users thinking the recommendation applies to host-local IPAM too, please reword to explicitly scope it to the calico-ipam plugin and use consistent Node field notation (and optionally mention podCIDRs for dual-stack).

Copilot uses AI. Check for mistakes.

:::

You can control which pools $[prodname] uses for each pod using

- node selectors
Expand Down
10 changes: 10 additions & 0 deletions ...rise_versioned_docs/version-3.20-2/networking/ipam/get-started-ip-addresses.mdx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,16 @@ The **calico-ipam** plugin uses $[prodname]’s IP pool resource to control how

By default, $[prodname] uses a single IP pool for the entire Kubernetes pod CIDR, but you can divide the pod CIDR into several pools. You can assign separate IP pools to particular selections of **nodes**, or to teams, users, or applications within a cluster using **namespaces**.

:::tip

Because Calico IPAM does not use the Kubernetes node CIDR allocations (`Node.spec.podCIDR`), you can set `--allocate-node-cidrs=false` on the kube-controller-manager.
This prevents Kubernetes from allocating unused node CIDRs and avoids `CIDRNotAvailable` events on nodes.

If you bootstrapped your cluster with kubeadm and passed `--pod-network-cidr`, kubeadm enables node CIDR allocation automatically.
See the [Kubernetes documentation](https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-reconfigure/) for instructions on reconfiguring the controller manager after cluster creation.
Comment on lines +29 to +33
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Copilot AI Mar 12, 2026

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The tip states Calico IPAM doesn’t use the Kubernetes node CIDR allocation (Node.spec.podCIDR), but the same page later documents host-local IPAM using Node.Spec.PodCIDR. Please clarify the tip applies specifically to the calico-ipam plugin and keep field naming consistent (and optionally mention podCIDRs for dual-stack).

Copilot uses AI. Check for mistakes.

:::

You can control which pools $[prodname] uses for each pod using

- node selectors
Expand Down
10 changes: 10 additions & 0 deletions ...rise_versioned_docs/version-3.21-2/networking/ipam/get-started-ip-addresses.mdx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,16 @@ The **calico-ipam** plugin uses $[prodname]’s IP pool resource to control how

By default, $[prodname] uses a single IP pool for the entire Kubernetes pod CIDR, but you can divide the pod CIDR into several pools. You can assign separate IP pools to particular selections of **nodes**, or to teams, users, or applications within a cluster using **namespaces**.

:::tip

Because Calico IPAM does not use the Kubernetes node CIDR allocations (`Node.spec.podCIDR`), you can set `--allocate-node-cidrs=false` on the kube-controller-manager.
This prevents Kubernetes from allocating unused node CIDRs and avoids `CIDRNotAvailable` events on nodes.

If you bootstrapped your cluster with kubeadm and passed `--pod-network-cidr`, kubeadm enables node CIDR allocation automatically.
See the [Kubernetes documentation](https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-reconfigure/) for instructions on reconfiguring the controller manager after cluster creation.
Comment on lines +29 to +33
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Copilot AI Mar 12, 2026

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This new tip is easy to misread as applying to all IPAM modes, but later the host-local IPAM section says it uses Node.Spec.PodCIDR. Please rephrase the tip to explicitly apply only when using the calico-ipam plugin and use consistent Node field notation (and optionally mention podCIDRs for dual-stack).

Copilot uses AI. Check for mistakes.

:::

You can control which pools $[prodname] uses for each pod using

- node selectors
Expand Down
10 changes: 10 additions & 0 deletions ...rise_versioned_docs/version-3.22-2/networking/ipam/get-started-ip-addresses.mdx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,16 @@ The **calico-ipam** plugin uses $[prodname]’s IP pool resource to control how

By default, $[prodname] uses a single IP pool for the entire Kubernetes pod CIDR, but you can divide the pod CIDR into several pools. You can assign separate IP pools to particular selections of **nodes**, or to teams, users, or applications within a cluster using **namespaces**.

:::tip

Because Calico IPAM does not use the Kubernetes node CIDR allocations (`Node.spec.podCIDR`), you can set `--allocate-node-cidrs=false` on the kube-controller-manager.
This prevents Kubernetes from allocating unused node CIDRs and avoids `CIDRNotAvailable` events on nodes.

If you bootstrapped your cluster with kubeadm and passed `--pod-network-cidr`, kubeadm enables node CIDR allocation automatically.
See the [Kubernetes documentation](https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-reconfigure/) for instructions on reconfiguring the controller manager after cluster creation.
Comment on lines +29 to +33
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Copilot AI Mar 12, 2026

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The new tip says Calico IPAM doesn’t use Node.spec.podCIDR, but later on the page host-local IPAM is documented as using Node.Spec.PodCIDR. To avoid a confusing contradiction, please scope the tip text to the calico-ipam plugin and keep the Node field naming consistent (and optionally mention podCIDRs for dual-stack).

Copilot uses AI. Check for mistakes.

:::

You can control which pools $[prodname] uses for each pod using

- node selectors
Expand Down
10 changes: 10 additions & 0 deletions ...rise_versioned_docs/version-3.23-1/networking/ipam/get-started-ip-addresses.mdx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,16 @@ The **calico-ipam** plugin uses $[prodname]’s IP pool resource to control how

By default, $[prodname] uses a single IP pool for the entire Kubernetes pod CIDR, but you can divide the pod CIDR into several pools. You can assign separate IP pools to particular selections of **nodes**, or to teams, users, or applications within a cluster using **namespaces**.

:::tip

Because Calico IPAM does not use the Kubernetes node CIDR allocations (`Node.spec.podCIDR`), you can set `--allocate-node-cidrs=false` on the kube-controller-manager.
This prevents Kubernetes from allocating unused node CIDRs and avoids `CIDRNotAvailable` events on nodes.

If you bootstrapped your cluster with kubeadm and passed `--pod-network-cidr`, kubeadm enables node CIDR allocation automatically.
See the [Kubernetes documentation](https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-reconfigure/) for instructions on reconfiguring the controller manager after cluster creation.
Comment on lines +29 to +33
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Copilot AI Mar 12, 2026

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This tip references Node.spec.podCIDR and is phrased generally as “Calico IPAM”, but later the same page describes host-local IPAM using Node.Spec.PodCIDR. Please make the tip explicitly about the calico-ipam plugin and align the Node field notation/capitalization (and optionally mention podCIDRs for dual-stack).

Copilot uses AI. Check for mistakes.

:::

You can control which pools $[prodname] uses for each pod using

- node selectors
Expand Down
10 changes: 10 additions & 0 deletions calico/networking/ipam/get-started-ip-addresses.mdx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,16 @@ The **calico-ipam** plugin uses Calico’s IP pool resource to control how IP ad

By default, Calico uses a single IP pool for the entire Kubernetes pod CIDR, but you can divide the pod CIDR into several pools. You can assign separate IP pools to particular selections of **nodes**, or to teams, users, or applications within a cluster using **namespaces**.

:::tip

Because Calico IPAM does not use the Kubernetes node CIDR allocations (`Node.spec.podCIDR`), you can set `--allocate-node-cidrs=false` on the kube-controller-manager.
This prevents Kubernetes from allocating unused node CIDRs and avoids `CIDRNotAvailable` events on nodes.

If you bootstrapped your cluster with kubeadm and passed `--pod-network-cidr`, kubeadm enables node CIDR allocation automatically.
See the [Kubernetes documentation](https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-reconfigure/) for instructions on reconfiguring the controller manager after cluster creation.
Comment on lines +29 to +33
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Copilot AI Mar 12, 2026

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The tip calls this out as "Calico IPAM" and references Node.spec.podCIDR, but later on this page the host-local IPAM section explicitly states it does use Node.Spec.PodCIDR. To avoid a confusing contradiction, consider rewording the tip to explicitly scope it to the calico-ipam plugin and align the field notation/capitalization (and optionally mention podCIDRs for dual-stack).

Copilot uses AI. Check for mistakes.

:::

You can control which pools Calico uses for each pod using

- node selectors
Expand Down
10 changes: 10 additions & 0 deletions calico_versioned_docs/version-3.29/networking/ipam/get-started-ip-addresses.mdx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,16 @@ The **calico-ipam** plugin uses Calico’s IP pool resource to control how IP ad

By default, Calico uses a single IP pool for the entire Kubernetes pod CIDR, but you can divide the pod CIDR into several pools. You can assign separate IP pools to particular selections of **nodes**, or to teams, users, or applications within a cluster using **namespaces**.

:::tip

Because Calico IPAM does not use the Kubernetes node CIDR allocations (`Node.spec.podCIDR`), you can set `--allocate-node-cidrs=false` on the kube-controller-manager.
This prevents Kubernetes from allocating unused node CIDRs and avoids `CIDRNotAvailable` events on nodes.

If you bootstrapped your cluster with kubeadm and passed `--pod-network-cidr`, kubeadm enables node CIDR allocation automatically.
See the [Kubernetes documentation](https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-reconfigure/) for instructions on reconfiguring the controller manager after cluster creation.
Comment on lines +29 to +33
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Copilot AI Mar 12, 2026

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The page later states host-local IPAM uses Node.Spec.PodCIDR, so the new tip (“Calico IPAM does not use… Node.spec.podCIDR”) can read as contradictory. Please reword to explicitly apply only to the calico-ipam plugin and use a consistent field notation (and optionally mention podCIDRs for dual-stack).

Copilot uses AI. Check for mistakes.

:::

You can control which pools Calico uses for each pod using

- node selectors
Expand Down
10 changes: 10 additions & 0 deletions calico_versioned_docs/version-3.30/networking/ipam/get-started-ip-addresses.mdx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,16 @@ The **calico-ipam** plugin uses Calico’s IP pool resource to control how IP ad

By default, Calico uses a single IP pool for the entire Kubernetes pod CIDR, but you can divide the pod CIDR into several pools. You can assign separate IP pools to particular selections of **nodes**, or to teams, users, or applications within a cluster using **namespaces**.

:::tip

Because Calico IPAM does not use the Kubernetes node CIDR allocations (`Node.spec.podCIDR`), you can set `--allocate-node-cidrs=false` on the kube-controller-manager.
This prevents Kubernetes from allocating unused node CIDRs and avoids `CIDRNotAvailable` events on nodes.

If you bootstrapped your cluster with kubeadm and passed `--pod-network-cidr`, kubeadm enables node CIDR allocation automatically.
See the [Kubernetes documentation](https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-reconfigure/) for instructions on reconfiguring the controller manager after cluster creation.
Comment on lines +29 to +33
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Copilot AI Mar 12, 2026

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This tip says Calico IPAM doesn’t use Kubernetes node CIDR allocations and references Node.spec.podCIDR, but the same page later describes host-local IPAM using Node.Spec.PodCIDR. To avoid confusion, please explicitly scope the tip to the calico-ipam plugin and keep the Node field notation consistent (and optionally mention podCIDRs for dual-stack).

Copilot uses AI. Check for mistakes.

:::

You can control which pools Calico uses for each pod using

- node selectors
Expand Down
10 changes: 10 additions & 0 deletions calico_versioned_docs/version-3.31/networking/ipam/get-started-ip-addresses.mdx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,16 @@ The **calico-ipam** plugin uses Calico’s IP pool resource to control how IP ad

By default, Calico uses a single IP pool for the entire Kubernetes pod CIDR, but you can divide the pod CIDR into several pools. You can assign separate IP pools to particular selections of **nodes**, or to teams, users, or applications within a cluster using **namespaces**.

:::tip

Because Calico IPAM does not use the Kubernetes node CIDR allocations (`Node.spec.podCIDR`), you can set `--allocate-node-cidrs=false` on the kube-controller-manager.
This prevents Kubernetes from allocating unused node CIDRs and avoids `CIDRNotAvailable` events on nodes.

If you bootstrapped your cluster with kubeadm and passed `--pod-network-cidr`, kubeadm enables node CIDR allocation automatically.
See the [Kubernetes documentation](https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-reconfigure/) for instructions on reconfiguring the controller manager after cluster creation.
Comment on lines +29 to +33
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Copilot AI Mar 12, 2026

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The tip calls this out as "Calico IPAM" and references Node.spec.podCIDR, but later on this page the host-local IPAM section states it uses Node.Spec.PodCIDR. To prevent readers from thinking this applies to host-local too, reword the tip to explicitly scope it to the calico-ipam plugin and use consistent field notation (and optionally mention podCIDRs for dual-stack).

Copilot uses AI. Check for mistakes.

:::

You can control which pools Calico uses for each pod using

- node selectors
Expand Down
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