I'm trying to migrate our ingress controllers from the old stable/nginx-ingress to the newer kubernetes/ingress-nginx
I have followed their instructions for zero downtime deployments.
Create a second nginx-controller with the kubernetes/ingress-nginx helm chart.
The instanceClassName has to be different than the original.
original instanceClassName: nginx
new instanceClassName: nginx2
Update dns to point to the new nginx 2 ELB.
Get rid of the old nginx-controller
This is all great, but all of our services/deployments are attached to instanceClassName: nginx. We can update the DNS, but then the services attached to it won't receive traffic. We can update the services at the same time, but they update at different times. This will cause an outage of some type while updating.
All of the research I have done seems to stop at that controller level. It doesn't go deeper and explain how to keep all the services connected during the switch.
How can I get both nginx controllers to route traffic to the application at the same time? I have not been able to get that to happen at the service or nginx controller level.
Or maybe I'm thinking about incorrectly, and it can work in a different way.
thanks.
There are multiple methods and I have given below with Istio and providing alternate method documentations for your reference.
You can avoid down time while migrating via splitting the traffic. There are few traffic splitting tools. Kubernetes has traffic splitting in-built feature with Istio and it will help you to direct a percentage of traffic to the new ingress controller while keeping the rest of the traffic on the old ingress controller.
Install Istio in your cluster and configure your ingress resources to use Istio gateway instead of the ingress controllers directly.
Install Istio in your cluster.
Configure your ingress resources to use the Istio gateway.
Create virtual service for your ingress resources and gradually increase the traffic to the new ingress controller and also make sure to update your DNS records to point to the new ingress controllers IP.
Reference and for further information please check the official Istio page and Istio Service Mesh Workshop.
For alternative methods please refer below options:
Canary Deployments and Type Loadbalancer
Related
According to this, it is possible to configure mirroring for a Traefik server.
Now I am using a Traefik ingress controller and want to configure mirroring. One possible solution seems to be using the CRD IngressRoute. While that would probably work, it is possible to configure mirroring also per annotation? This would allow me to rely on the Kubernetes Ingress abstraction instead of using CRDs.
The background of that is, that I don't want to make assumptions about which technology is used an ingress controller.
Currently, we are using a loadbalancer type srevice for routing external requests to one of our pods.
We would like to move this to an ingress type service ( there is already an external load balancer setup along with an ingress controller - and we do have other pods configured to receive external requests via this ingress controller)
What we have now is the below url, used by the clients to connect externally:
ws://streamevents.app.com:7080/stomp
wss://streamevents.app.com:7443/stomp
We would like to move it to
ws://streameventsv2.app.com/stomp
wss://streameventsv2.app.com/stomp
This way, we can free up the loadbalancer IP and do not need specific ports. We do want to support both url's together for a while - since clients are already connecting to the old one. How could we achieve this?
Options I can think of (we use helm):
Create a separate chart and deployment with the Ingress service - the old one still uses the LoadBalancer
Same chart - expose the service both ways (is this really possible?)
Change the current one to Ingress - and somehow also make sure we route requests to the old url to the new ingress (how?)
Or any other possible approaches?
I'm guessing you own the helm chart and hence you can make changes to it. If so, you can expose your service both using Ingress and LoadBalancer service. You don't need any changes in any other resources in the helm chart other than adding an Ingress resource. You can remove the LoadBalancer object when you can stop supporting it.
In GKE Ingress documentation
it states that:
When you create an Ingress object, the GKE Ingress controller creates a Google Cloud HTTP(S) Load Balancer and configures it according to the information in the Ingress and its associated Services.
To me it seems that I can not have multiple ingress resources with single GCP ingress controller. Instead, GKE creates a new ingress controller for every ingress resource.
Is this really so, or is it possible to have multiple ingress resources with a single ingress controller in GKE?
I would like to have one GCP LoadBalancer as ingress controller with static IP and DNS configured, and then have multiple applications running in cluster, each application registering its own ingress resource with application specific host and/or path specifications.
Please note that I'm very new to GKE, GCP and Kubernetes in general, so it might be that I have misunderstood something.
I think the question you're actually asking is slightly different than what you have written. You want to know if multiple Ingress resources can be linked to a single GCP Load Balancer, not GKE Ingress controller. Based on the concept of a controller, there is only one GKE Ingress controller in a cluster, which is responsible for fulfilling multiple resources and provisioning multiple load balancers.
So, to answer the question directly (because I've been searching for a straight answer for a long time!):
Combining multiple Ingress resources into a single Google Cloud load
balancer is not supported.
Source: https://cloud.google.com/kubernetes-engine/docs/concepts/ingress
Sad.
However, using the nginx-ingress controller is one way to at least minimize the number of external (GCP) load balancers provisioned (it only provisions a single TCP load balancer), but since the load balancer is for TCP traffic, it cannot terminate SSL, or apply Firewall rules for you (Cloud Armor cannot be used, for instance).
The only way I know of to have a single HTTPS load-balancer in GCP terminate SSL and route traffic to multiple services in GKE is to combine the ingresses into a single resource with all paths and certificates defined in one place.
(If anybody figures out a way to do it with multiple separate ingress resources, I'd love to hear it!)
Yes it is possible to have the single ingress controller for multiple ingress resources.
You can create multiple ingress resources as per path requirement and all will be managed by single ingress controller.
There are multiple ingress controller options also available you can use Nginx also that will create one LB and manage the paths.
Inside Kubernetes if you are creating a service with type LoadBalancer it will create the new LB resource in GCP so make sure your microservice type is ClusterIP and your all traffic goes inside K8s cluster via ingress path.
When you setup the ingress controller it will create one service with type LoadBalancer you can can use that IP in DNS servers to forward the subdomain and path to K8s cluster.
Good morning guys, so I took down a staging environment for a product on GCP and ran the deployment scripts again, the backend and frontend service have been setup. I have an ingress resource and a load balancer up, however, the service is not running. A look at the production app revealed there was something like an nginx-ingress-controller. I really don't understand all these and how it was created. Can someone help me understand because I have not seen anything online that makes it clear for me. Am I missing something?
loadBalancer: https://gist.github.com/davidshare/5a571e56febe7dacd580282b373f3095
Ingress Resource: https://gist.github.com/davidshare/d0f53912bc7da8310ec3d64f1c8a44f1
Ingress allows access to your Kubernetes services from outside the Kubernetes cluster. There are different kubernetes aka K8 resources alternatively you can use like (Node Port / Loadbalancer) which you can use to expose.
Ingress is independent resource to your service , you can specify routing rules declaratively, so each url with some context can be mapped to different services.
This makes it decoupled and isolated from the services you want to expose.
So to work ingress it needs an Ingress Controller for your cluster.
Like deployment resource in K8, ingress can be created simply by
kubectl create -f ingress.yaml
First, you have to implement Ingress Controller in order to apply Ingress resource, as described in #Shubhu answer. Ingress controller, as an edge router, applies specific logical structure with aim to route external traffic to your Kubernetes cluster underlying services via basic pattern routing rules defined in Ingress resource.
If you select Nginx Ingress Controller then it might be useful to proceed with installation guide approaching some specific prerequisites based on cloud provider environment. In order to simplify Nginx Ingress controller installation procedure it is also possible to use Helm package manager and install appropriate stable/nginx-ingress Helm chart.
I am new to Kubernetes and wanted to understand how I can expose a service running in Kubernetes to the outside world. I have exposed it using a NodePort on the cluster.
So, for example: A service exposes port 31234 on the host and I can get to the service from another server through https://kubeserverIP:31234.
What I want to achieve is serve this service through nginx (on a different server, out of Kube control) via a url,say, http://service.example.com. I have tried deploying nginx with an upstream pointing to the service but that is not working and get a bad gateway error.
Is there something which I am missing here? Or is there a neater way of achieving this.
I have a baremetal installation of Kubernetes cluster and have no access to gce load balancer or other vendor LBs.
Thanks
Thanks for pointing in the right direction.
Essential steps broadly were:
Create an app and its service definition.
Create a namespace for ingress.
Create a default backend deployment and service for redirecting all requests not defined in Ingress rules. Create these in the ingress space
Create the nginx ingress controller deployment.
Create RBAC rules.
Finally create the ingress rule for the applications with the paths and the ports.
Found a very useful guide which explained things in details:
https://akomljen.com/kubernetes-nginx-ingress-controller/
You're almost there! Your next step will be to setup a ingress controller. There is an NGINX Ingress controller plugin that you can checkout here.
Edit: Here's an example configuration: https://github.com/nginxinc/kubernetes-ingress/tree/master/examples/complete-example