Can IPAM manage the IPs already assigned to a VPC

Question

Parts of the AWS Load Balancer web console UI suggests that certain IP management tasks require setting up an "IPAM" object, but gives no explanation or obvious link to an explanation.  I have tried setting up a "free tier" IPAM, but see no way to make it do anything with the already assigned resources (Elastic public IPv4s, VPC manually assigned private IPv4 subnets under 10.0.0.0/8, EC2 manually assigned individual ENI IPv4s, VPC assigned AWS public IPv6 /56 nets, VPC manually assigned IPv6 /64 subnets and EC2 manually assigned individual ENI IPv6s), nor does it seem to provide me additional information about the AWS assigned Load Balancer IPs .

This is a single organization setup, not a multi-organization management scenario.

So the questions are:
1. Can IPAM manage individual Elastic public IPv4 addresses obtained in the via the usual VPC mechanisms.
2. Can IPAM manage the AWS assigned IPv6 /56 subnet already assigned to a VPC.
3. Can management of existing address resources be moved from VPC and EC2 methods to IPAM based mechanisms without disrupting the services already provided to clients at those addresses.

re:Post Agent · Answer

IPAM (IP Address Manager) is indeed a powerful tool for managing IP addresses across your AWS resources, but it has some limitations when it comes to managing pre-existing IP allocations. Let's address your questions one by one:

1. Regarding individual Elastic public IPv4 addresses: IPAM does not directly manage individual Elastic IP addresses that have been obtained through standard VPC mechanisms. IPAM is primarily designed for managing IP address pools and allocations, rather than individual public IP addresses.

2. For AWS-assigned IPv6 /56 subnets already assigned to a VPC: IPAM can manage and monitor IPv6 address space, including public and private IPv6 addresses. However, it doesn't automatically take control of existing IPv6 allocations. You would need to set up IPAM pools that include your existing IPv6 ranges to start managing them through IPAM.

3. Regarding moving management of existing address resources to IPAM: Unfortunately, IPAM doesn't provide a seamless way to take over management of existing IP allocations without potential disruption. IPAM is most effective when used from the beginning of your IP address planning and allocation process. For existing resources, you would need to manually align your IPAM configuration with your current IP address usage, which could be a complex process.

It's important to note that IPAM is more focused on planning, allocating, and monitoring IP address usage across your AWS organization, rather than managing individual IP addresses assigned to specific resources. While it can provide valuable insights and help prevent IP conflicts, it doesn't replace the existing VPC and EC2 methods for assigning and managing individual IP addresses.

For your single-organization setup, IPAM can still be useful for future planning and allocation of IP addresses, but it won't automatically solve IP management issues for your existing resources. You would need to carefully plan how to incorporate your existing IP allocations into IPAM if you decide to use it going forward.  
**Sources**  
[How IPAM works - Amazon Virtual Private Cloud](https://docs.aws.amazon.com/vpc/latest/ipam/how-it-works-ipam.html)  
[IPAM - AWS Prescriptive Guidance](https://docs.aws.amazon.com/prescriptive-guidance/latest/robust-network-design-control-tower/ipam.html)

Can IPAM manage the IPs already assigned to a VPC

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