Public IP not allocated after Instance redeployed

[tregin]

Hello I have a following problem.

I have an EC2 instance which I'm deploying to the PUBLIC subnet. I understand by doing this the Instance should be automatically provisioned with Public IP address.

Instance is configured to have primary and secondary ENI.

• Primary to have Public and Private IP
• Secondary to have only Private IP
  When I deploy my instance for the first time it is deployed without any issues and Public IP is assigned to the instance.

But then for example when I make changes to the startup script of the instance and re-deploy again, EC2 Instance is not getting Public IP assigned. (only Private IP for both ENIs)

When I deploy the instance without the secondary ENI the redeployment works fine but with the secondary ENI deployment present it doesn't work and the Public IP is not assigned.

Does someone has similar experience?

Stack is deployed with: cdkVersion: '2.20.0'

Expected Behavior

Public IP should be assigned to instance after CDK redeployment

Current Behavior

Public IP should is only assigned during first deployment

CODE snippet:

      const ec2Instance = new Instance(this, 'instance', {
      instanceName: `${props.stageName}-${componentName}-instance`,
      vpc: props.vpc,
      userData: UserData.custom(readTemplate),
      vpcSubnets: { subnetType: SubnetType.PUBLIC },
      instanceType: new InstanceType(props.instanceType),
      securityGroup: securityGroup,
      machineImage: image,
      role: instanceRole,
      keyName: key.keyPairName,
    });

    // Create additional ENI
    const cfnNetworkInterface = new CfnNetworkInterface(this, 'secondary-eni', {
      subnetId: props.vpc.selectSubnets({ subnetType: SubnetType.PRIVATE_WITH_NAT }).subnetIds[0],
      description: 'secondary ENI',
      groupSet: [securityGroup.securityGroupId],
    });

    new CfnNetworkInterfaceAttachment(this, 'network-attachment', {
      deviceIndex: '1',
      instanceId: ec2Instance.instanceId,
      networkInterfaceId: cfnNetworkInterface.attrId,
      deleteOnTermination: true,
    });`