I have a k8s cluster that I run. I have the necessary scripts that can create the cluster and destroy it as necessary. I have some of my applications running on this cluster. Recently I configured Ingress controller service and I'm routing my traffic to the application services via this Ingress controller.
I would like to access the application using a hostname where I have defined this in my Ingress rules. For example., when I need to access application A, which has a service IP like 192.168.0.100, I would use the hostname application.a.local. For this I need to edit the /etc/hosts file on the machine that is running the cluster and add an entry there. This is a manual approach. How could I automate this?
Is there a better approach to configure hostname mapping? Any suggestions?
Related
I understand there are various ways to get external traffic into the cluster - Ingress, cluster IP, node port and load balancer. I am particularly looking into the Ingress and k8s and from the documentation k8s supports AKS, EKS & Nginx controllers.
https://kubernetes.io/docs/concepts/services-networking/ingress-controllers/
To implement Ingress, understand that we need to configure an Ingress Controller in the cluster. My query is whether Nginx ingress & proxy are an offering of core k8s (packaged / embedded)? Might have overlooked, did not find any documentation where it is mentioned. Any insight or pointer to documentation if stated above is true is highly appreciated.
Just reading the first rows of the page you linked, it states that no controller are started automatically with a cluster and that you must choose the one of your preference, depending on your requirements
Ingress controllers are not started automatically with a cluster. Use
this page to choose the ingress controller implementation that best
fits your cluster.
Kubernetes defines Ingress, IngressClass and other ingress-related resources but a fresh installation does not come with any default.
Some prepackaged installation of Kubernetes (like microk8s, minikube etc...) comes with ingress controller that, usually, needs to be enabled manually during the installation/configuration phase.
As far as I know, Instance Management and the Controller have the same functions, which managing NGINX Plus and the Instances. but it does not make more sense.
So my question is
What are the differences between Instance Management and Controller?
What is Ingress Controller?
Nginx Instance Management: NGINX Instance Manager empowers you to
Automate configuration and monitoring using APIs.
For example, if you have multiple servers using Nginx then in Nginx Plus service provides a dashboard where all the events can be monitored, Including spikes on specific events, Or think as one of the servers has not been updated from having multiple VM, monitor the list of inventory. To achieve nginx-agant needs to install along with Nginx server on the host.
Ensure your fleet of NGINX web servers and proxies have fixes for
active CVEs
Seamlessly integrate with third‑party monitoring solutions such as
Prometheus and Grafana for insights
Nginx Controller: NGINX Controller is cloud‑agnostic and includes a set of enterprise‑grade services that give you a clear line of sight to apps in development, test, or production. With per‑app analytics, you gain new insights into app performance and reliability so you can pinpoint performance issues before they impact production.
Example: To enable the ingress you did need an Ingress Controller to enabled first.
Nginx Ingress: Each LoadBalancer service requires its own load balancer with its own public IP address, whereas an Ingress only requires one, even when providing access to dozens of services. When a client sends an HTTP request to the Ingress, the host and path in the request determine which service the request is forwarded to.
For example Google Kubernetes Controller
I have a Load Balancer IP provided by OVH that I want to use with Nginx Ingress Controller but on a on-premises cluster. There are several guide s to do that using OVH Managed Kubernetes but it is not possible for me since I already a cluster.
I tried to use the LoadBalancerIP option using Helm and without Helm as well...
You should expose Nginx Ingress Controller as NodePort and point your OVH Load Balancer to your workers as endpoints.
User ---> OVH LB ----> Nginx Ingress on workers
Thank you for both you answer. I tried what you recommended but I think I'm missing a point. TO be more clear :
1/ The user part -> I have a OVH LB connected to a server of 3 node, this LB selects a node to be used by a user (round robin)
2/ Once a node had been selected, the user should be able to access to whatever service inside Kubernetes even if the service is not on this node by using the LoadBalancer IP.
For the 2nd point, I tried to expose/create an endpoint for the Nginx Ingress Controller where I gave the LB's IP, but I don't know if I have to create an Ingress object for each service (only 2-3 like grafana, prometheus..). I tried it but it didn't work. I also tried to create an Ingress for the service where I gave the LB IP but it didn't work. Note that my k8s cluster is on LXD containers which are inside 3 connected servers (one LXD container by server node). Also, concerning the OVH LoadBalancer, I'm not very confident with the purpose of Outbound IPs (which is a CIDR range)..
I understand that my OVH LB cannot be auto provisioned, but since its job is done outside of k8s (just attributing a node to a user), the problem is : how does the node can access the service based on a URL like grafana.example.com? I was using MetalLB as an internal LB and it worked fine but now i'm struggling with the OVH LB..
I want to use Nginx to load balance a kubernetes deployment.
The deployment is part of a service. It contains pod which can be scaled. I want NGINX to be part of the service without being scaled.
I know that I can use NGINX as an external load balancer by configuring it with external dns resolver. With that it can get the IP of the pods scaled and apply its own load balanced rules.
Is it possible to make NGINX part of the service? Then how to do the DNS resolution to the pods? In that case, which pods the service name is refered to?
I would like to avoid the declaration of two services to keep a single definition of the setup which represent a microservice.
More generally, how can I declare in a same service:
a unit which is scaled
a backend, not scaled
a database, not scaled
Thanks all
You can't have NGINX as part of the service. Service doesn't contain any pods, deployment does. It sounds like you want an ingress service, that would be a load balancer any and all services on the cluster
EDIT:
An ingress controller in essence is a deployment of NGINX exposed publicly as a service acting as a load balancer/fan out. The deployment scans your cluster for ingress resources and reconfigures NGINX to forward requests to appropriate services.
Typically people deploy a single controller that acts as the load balancer for all of your microservices. You can fan out based on DNS, URI, other headers and so on. You can also do TLS termination, add basic auth to specific services, it's even possible to splice in NGINX config snippets directly into the ingress resources.
I'm looking for a way, if possible to route a request to for eg. team.mysite.com to team.default.svc.cluster.local using nginx. This way I could have multiple wordpress sites using different sub domains on my domains and working as explained above. Basically calling xyz.mysite.com would have the request forwarded to xyz.default.svc.cluster.local, provided the service exists.
Note:
I have the kube-dns service running at 10.254.0.2
Is this possible? And how exactly would I do this?
Thanks.
Edit:
Going over this again I could possibly use variables in the ngonx.conf i.e $host.$host.default.svc.cluster.conf where $host is $host.mydomain.com.
I'd need a way to let nginx resolve the kube dns services also a way to part out the xyz in xyz.mydomain.com in the nginx.conf and assigning it to $host
If your nodes have a public IP address you could use an Ingress resource to do exactly what you describe. An Ingress usually defines a list of paths and their target Service, so your service should be running before you try to expose it.
Ingress controllers then dynamically configure Web servers that listen on a defined list of ports for you (typically the host ports 80 and 443 as you may have guessed) using the Ingress configuration mentioned above, and can be deployed using the Kubernetes resource type of your choice: Pod, ReplicationController, DaemonSet.
Once your Ingress rules are configured and your Ingress controller is deployed, your can point the A or CNAME DNS records of your domain to the node(s) running the actual Web server(s).