​​NLB + Security Groups

https://docs.aws.amazon.com/elasticloadbalancing/latest/network/load-balancer-security-groups.html

✅ You can associate SG with NLB when you create it.

✅ After you create NLB with associated SG, you can change SG associated with NLB at any time.

👉 If you create NLB without associating any SG, you can't associate them with NLB later on.

⚠️ Health checks are subject to outbound rules, but not inbound rules. You must ensure that outbound rules don't block health check traffic. Otherwise, NLB considers the targets unhealthy.

✅ You can control whether PrivateLink traffic is subject to inbound rules. If you enable inbound rules on PrivateLink traffic, the source of the traffic is the private IP address of the client, not the endpoint interface.

#NLB #SG