Weighted allocation

When multiple resources can be allocated from a pool, you can control the allocation order using weights. Resources with higher weights are allocated first.

Prefix pool & Address pool

While this guide uses IP address pools, the same principles apply to IP prefix pools.

Prerequisites

A running Infrahub instance
Basic familiarity with IP address pools (see Allocate IP addresses)

The examples on this page require your IP prefix node to inherit from CoreWeightedPoolResource. This adds an allocation_weight attribute to the node.

nodes:
  - name: IPPrefix
    namespace: Ipam
    inherit_from:
      - "BuiltinIPPrefix"
      - "CoreWeightedPoolResource"

Step 1: Create a low-weight prefix

Create a prefix with a lower allocation weight:

Web interface
GraphQL

Navigate to IPAM → IP Prefixes and create a new prefix with:

Prefix: 10.100.5.0/24
Member Type: address
Allocation Weight: 100

Click Save.

mutation {
  IpamIPPrefixCreate(
    data: {
      prefix: {value: "10.100.5.0/24"}
      member_type: {value: "address"}
      allocation_weight: {value: 100}
    }
  ) {
    ok
    object {
      id
    }
  }
}

important

Save the prefix ID for the next step!

Step 2: Create a high-weight prefix

Create a second prefix with a higher allocation weight:

Web interface
GraphQL

Navigate to IPAM → IP Prefixes and create a new prefix with:

Prefix: 10.100.6.0/24
Member Type: address
Allocation Weight: 200

Click Save.

mutation {
  IpamIPPrefixCreate(
    data: {
      prefix: {value: "10.100.6.0/24"}
      member_type: {value: "address"}
      allocation_weight: {value: 200}
    }
  ) {
    ok
    object {
      id
    }
  }
}

important

Save the prefix ID for the next step!

Step 3: Create a pool with both prefixes

Create a CoreIPAddressPool Resource Manager referencing both prefixes:

Web interface
GraphQL

Navigate to Object Management → Resource Manager and create a new IP Address Pool with:

Name: My Weighted IP address pool
Default Address Type: IpamIPAddress
Default Prefix Length: 24
Resources: Select the 10.100.5.0/24 and 10.100.6.0/24 prefixes
IP Namespace: default

mutation {
  CoreIPAddressPoolCreate(
    data: {
      name: {value: "My Weighted IP address pool"}
      default_address_type: {value: "IpamIPAddress"}
      default_prefix_length: {value: 24}
      resources: [
        {id: "<prefix01-id>"},
        {id: "<prefix02-id>"}
      ]
      ip_namespace: {id: "default"}
    }
  ) {
    ok
    object {
      id
      hfid
    }
  }
}

Step 4: Allocate from the pool

mutation {
  InfrahubIPAddressPoolGetResource(
    data: {
      hfid: ["My Weighted IP address pool"]
      data: {description: "my first allocated ip"}
    }
  ) {
    ok
    node {
      id
      display_label
    }
  }
}

Weighted allocation

You should have received an IP address from the 10.100.6.0/24 prefix, as it has a higher weight (200) than 10.100.5.0/24 (100).

Prerequisites​

Step 1: Create a low-weight prefix​

Step 2: Create a high-weight prefix​

Step 3: Create a pool with both prefixes​

Step 4: Allocate from the pool​

Next​

Prerequisites

Step 1: Create a low-weight prefix

Step 2: Create a high-weight prefix

Step 3: Create a pool with both prefixes

Step 4: Allocate from the pool

Next