kubectl describe svc ingress-nginx-controller -n ingress-nginx
Events: Type Reason Age From Message
Warning SyncLoadBalancerFailed 50m (x19 over 4d13h) service-controller Error syncing load balancer: failed to ensure load balancer: Multiple untagged security groups found for instance i-075eead94185e5783; ensure the k8s security group is tagged Warning SyncLoadBalancerFailed 45m (x48 over 11d) service-controller Error syncing load balancer: failed to ensure load balancer: Multiple untagged security groups found for instance i-04524256cf8e67e1c; ensure the k8s security group is tagged Warning SyncLoadBalancerFailed 35m (x39 over 5d14h) service-controller Error syncing load balancer: failed to ensure load balancer: Multiple untagged security groups found for instance i-04c7e38857adb8b81; ensure the k8s security group is tagged Normal EnsuringLoadBalancer 5m1s (x3277 over 11d) service-controller Ensuring load balancer Warning SyncLoadBalancerFailed 5m (x2141 over 11d) service-controller (combined from similar events): Error syncing load balancer: failed to ensure load balancer: Multiple untagged security groups found for instance i-0724b0ac397085d99; ensure the k8s security group is tagged
EKS Service 리소스에서 LoadBalancer 타입을 생성할 때,
Kubernetes Service Controller는 노드에 연결된 보안 그룹(Security Group) 중
Kubernetes 관련 태그(kubernetes.io/cluster/<cluster-name>)가 지정된 보안 그룹을 식별하여 로드밸런서와 연결한다.
그러나 해당 노드에 여러 개의 태그되지 않은(Security Group Tag 누락) 보안 그룹이 동시에 연결되어 있어,
컨트롤러가 어떤 SG를 사용해야 할지 판단하지 못해 오류가 발생