Lambda in VPC won't create new ENI after an ENI has been manually detached from subnet

Question

I have run into a problem where my Lambda functions can no longer create new ENI\'s in a VPC subnet once an ENI has been detached and deleted from that subnet. I have reproduced

Answer 1

I recently faced a similar issue. I couldn't delete sg or subnets since they were being used by other stacks. I figured out if I force lambda to cold start, it might create new eni. To test this I allocated max memory and timeout. It worked.