Question

How to reuse DO LoadBalancer previously created through Kubernetes?

Posted on November 15, 2018
Load Balancing Kubernetes
Asked by Dennis Stritzke

Hi,

when creating a Kubernetes cluster and using a load balancer to host any public service, its easy to imagine that there would be anything going terribly wrong with the cluster. In that case I would like to create a new cluster and reuse the LoadBalancer to still have the same Public IP has before. Is there a possibility to request a specific load balancer name to be reused within the service definition? Or is elastic ip support for LoadBalancers planned?

This would increase fix possibilities in cases where there are infrastructure issues.

Dennis

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Tyler C

DigitalOcean Employee

• November 16, 2018

Accepted Answer

Hi Dennis,

Thanks for your question. I’m Tyler, the product manager for our Load Balancer product. At this point in time, it’s not possible to re-use an existing LB. It has to be generated as a new LB in order to get registered in k8s properly and things to be routed correctly. This wouldn’t be impossible, per se, but it’s not something we’re looking to add soon, unfortunately.

I will say that we are considering working on adding floating IP support to Load Balancers, which completes part of your request. This would be something that would likely happen in mid-2019.

3fc8c30ccd8d45fbaa476a72534ce7 • January 3, 2021

I tried the following approach to resolve the issue with keeping the same DOLB its IP and so on. Looks like works for me.

Setup your DOLB manually
Change service type to NodePort, provide prefered nodePort values.
Provide your externalIP for DOLB, you can probably provide it using properties
On your DOLB setup forwarding rules, in my case is

TCP on port 443  TCP on port 30443
TCP on port 80  TCP on port 30080

On yor DOLB setup health checks, in my case is

tcp://0.0.0.0:30080

Enjoy your Load Balancer and not-changing IP you can use to configure DNS.

apiVersion: v1
kind: Service
metadata:
  annotations:
    service.beta.kubernetes.io/aws-load-balancer-backend-protocol: tcp
    service.beta.kubernetes.io/aws-load-balancer-type: nlb
  name: kong-proxy
  namespace: kong
spec:
  ports:
    - name: proxy
      **nodePort: 30080**
      port: 80
      protocol: TCP
      targetPort: 8000
    - name: proxy-ssl
      **nodePort: 30443** 
      port: 443
      protocol: TCP
      targetPort: 8443
  externalIPs: 
    - 111.111.111.111 # IP of your DO manually created load balancer 
  selector:
    app: ingress-kong
  **type: NodePort**

Alexis Charytonow • October 26, 2019

Hi, I’m analyzing k8s infrastructure in DO to start using it as a permanent solution. I’m facing this issue now and it doesn’t look good to not be able to reuse a previous IP address. If the cluster has any issues and there’s a need to regenerate it (or maybe there’s a need to do a cleanup), the traffic will be “dead” until DNS change takes effect for the new load balancer. Is there any fix planned for this situation?