Kubernetes (docker-desktop) with multiple LoadBalancer services - docker

Question

Is it true that I cannot have two LoadBalancer services on a docker-desktop cluster (osx), because they would both use localhost (and all ports are forwarded)?
I created an example and the latter service is never assigned an external IP address but stays in state pending. However, the former is accessible on localhost.
> kubectl get all
NAME READY STATUS RESTARTS AGE
pod/whoami-deployment-9f9c86c4f-l5lkj 1/1 Running 0 28s
pod/whoareyou-deployment-b896ddb9c-lncdm 1/1 Running 0 27s
pod/whoareyou-deployment-b896ddb9c-s72sc 1/1 Running 0 27s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 95s
service/whoami-service LoadBalancer 10.97.171.139 localhost 80:30024/TCP 27s
service/whoareyou-service LoadBalancer 10.97.171.204 <pending> 80:32083/TCP 27s
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/whoami-deployment 1/1 1 1 28s
deployment.apps/whoareyou-deployment 2/2 2 2 27s
NAME DESIRED CURRENT READY AGE
replicaset.apps/whoami-deployment-9f9c86c4f 1 1 1 28s
replicaset.apps/whoareyou-deployment-b896ddb9c 2 2 2 27s
Detailed state fo whoareyou-service:
kubectl describe service whoareyou-service
Name: whoareyou-service
Namespace: default
Labels: <none>
Annotations: kubectl.kubernetes.io/last-applied-configuration:
{"apiVersion":"v1","kind":"Service","metadata":{"annotations":{},"name":"whoareyou-service","namespace":"default"},"spec":{"ports":[{"name...
Selector: app=whoareyou
Type: LoadBalancer
IP: 10.106.5.8
Port: http 80/TCP
TargetPort: 80/TCP
NodePort: http 30333/TCP
Endpoints: 10.1.0.209:80,10.1.0.210:80
Session Affinity: None
External Traffic Policy: Cluster
Events: <none>

Answer 1

I decided to copy my comments, as they partially explain the problem, and make a Community Wiki answer out of them so it is more clearly seen and available for possible further edits by the Community:
It works probably exactly the same way as in Minikube. As docker-desktop is unable to provision real LoadBalancer it can still "simulate" creating Service of such type using NodePort (this can easily be seen from port range it uses). I'm pretty sure you cannot use same IP address as the ExternalIP of the LoadBalancer Service and if you create one more Service of such type, your docker-desktop has no other choice than to use your localhost one more time. As it is already used by one Service it cannot be used by another one and that's why it remains in a pending state.
Note that if you create real LoadBalancer in a cloud environment, each time new IP is provisioned and there is no situation that next LoadBalancer you create gets the same IP that is already used by the existing one. Apparently here it cannot use any other IP then one of localhost, and this one is already in use. Anyway I would recommend you to simply use NodePort if you want to expose your Deployment to the external world.

Answer 2

Think about using Ingress controller instead.
So basically, it's 3 steps after installing docker-desktop :
Wilcard Certificate locally
SSL certificate For local env
Install Ingress Controller
Detailed here: https://github.com/kubernetes-tn/guideline-kubernetes-enterprise/blob/master/general/desktop-env-setup.md

Answer 3

I came across this question while looking to set up a lightweight local environment with minimal dependencies.
I found that two LoadBalancer work on localhost when using different port numbers.
---
apiVersion: v1
kind: Service
metadata:
name: webapp-one-lb
spec:
ports:
- name: 8081-tcp
port: 8081
protocol: TCP
targetPort: 8080
selector:
name: webapp-one
type: LoadBalancer
status:
loadBalancer: {}
---
apiVersion: v1
kind: Service
metadata:
name: webapp-two-lb
spec:
ports:
- name: 8082-tcp
port: 8082
protocol: TCP
targetPort: 8080
selector:
name: webapp-two
type: LoadBalancer
status:
loadBalancer: {}
As others have said, Ingress is more flexible and allows for sub-domain and path based routing without having to worry about port conflicts, but it comes with an additional learning curve.