Software Engineering

[Solved] Network interface is in use by another service in AWS

If you have tried to delete a Security Group, or VPC, or various other resources and you get the dreaded Network interface is in use by another service error, then you can resolve this by deleting the resource through the API.

How to delete the Network Interface (ENI)

aws ec2 delete-network-interface --network-interface-id eni-xxxxx

Replace the eni-xxxxx with the ENI id that you are struggling to delete.

How to find what services are using the ENI

aws ec2 describe-internet-gateways --filters 'Name=attachment.vpc-id,Values='$vpc | grep InternetGatewayId
aws ec2 describe-subnets --filters 'Name=vpc-id,Values='$vpc | grep SubnetId
aws ec2 describe-route-tables --filters 'Name=vpc-id,Values='$vpc | grep RouteTableId
aws ec2 describe-network-acls --filters 'Name=vpc-id,Values='$vpc | grep NetworkAclId
aws ec2 describe-vpc-peering-connections --filters 'Name=requester-vpc-info.vpc-id,Values='$vpc | grep VpcPeeringConnectionId
aws ec2 describe-vpc-endpoints --filters 'Name=vpc-id,Values='$vpc | grep VpcEndpointId
aws ec2 describe-nat-gateways --filter 'Name=vpc-id,Values='$vpc | grep NatGatewayId
aws ec2 describe-security-groups --filters 'Name=vpc-id,Values='$vpc | grep GroupId
aws ec2 describe-instances --filters 'Name=vpc-id,Values='$vpc | grep InstanceId
aws ec2 describe-vpn-connections --filters 'Name=vpc-id,Values='$vpc | grep VpnConnectionId
aws ec2 describe-vpn-gateways --filters 'Name=attachment.vpc-id,Values='$vpc | grep VpnGatewayId
aws ec2 describe-network-interfaces --filters 'Name=vpc-id,Values='$vpc | grep NetworkInterfaceId