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
Related
I'm currently working on a project where we are using Google Cloud. Within the Cloud we are using CloudRun to provide our services. One of these services is rather complex and has many different configuration options. To validate how these configurations affect the quality of the results and also to evaluate the quality of changes to the service, I would like to proceed as follows:
in addition to the existing service I deploy another instance of the service which contains the changes
I mirror all incoming requests and let both services process them, only the responses from the initial service are returned, but the responses from both services are stored
This allows me to create a detailed evaluation of the differences between the two services without having to provide the user with potentially worse responses.
For the implementation I have setup a NGINX which mirrors the requests. This is also deployed as a CloudRun service. This now accepts all requests and takes care of the authentication. The original service and the mirrored version have been configured in such a way that they can only be accessed internally and should therefore be accessed via a VPC network.
I have tried all possible combinations for the configuration of these parts but I always get 403 or 502 errors.
I have tried setting the NGINX service to the HTTP and HTTPS routes from the service, and I have tried all the VPC Connector settings. When I set the ingress from the service to ALL it works perfectly if I configure the service with HTTPS and port 443 in NGINX. As soon as I set the ingress to Internal I get errors with HTTPS -> 403 and with HTTP -> 502.
Does anyone have experience in this regard and can give me tips on how to solve this problem? Would be very grateful for any help.
If your Cloud Run service are internally accessible (ingress control set to internal only), you need to perform your request from your VPC.
Therefore, as you perfectly did, you plugged a serverless VPC connector on your NGINX service.
The set up is correct. Now, why it works when you route ALL the egress traffic and not only the private traffic to your VPC connector?
In fact, Cloud Run is a public resource, with a public URL, and even if you set the ingress to internal. This param say "the traffic must come to the VPC" and not say "I'm plugged to the VPC with a private IP".
So, to go to your VPC and access a public ressource (Your cloud run services), you need to route ALL the traffic to your VPC, even the public one.
I followed this guide: https://www.digitalocean.com/community/tutorials/how-to-set-up-an-nginx-ingress-with-cert-manager-on-digitalocean-kubernetes on how to setup an Nginx Ingress with Cert Manager with Kubernetes having DigitalOcean as a cloud provider.
The tutorial worked fine, I was able to setup everything according to what it was written. Though, (as it is stated) following the tutorial one ends up with three pods of which only one is in "Running 1/1", while the other two are "Down". Also when checking the comments section, it seems that it is quite a problem. Since if all the traffic gets routed to only 1 pods, it is not really scalable. Or am I missing something? Quoting from their tutorial:
Note: By default the Nginx Ingress LoadBalancer Service has
service.spec.externalTrafficPolicy set to the value Local, which
routes all load balancer traffic to nodes running Nginx Ingress Pods.
The other nodes will deliberately fail load balancer health checks so
that Ingress traffic does not get routed to them.
Mainly my question is: Is there a best practice that I am missing in order to have Kubernetes hosting my website? It seems I have to choose either scalability (having all the pods healthy and running) or getting IP of the client visitor.
And for whoever will ever find himself/herself in my situation, this is the reply I got from the DigitaOcean Support:
Unfortunately with that Kubernetes setup it would show those other
nodes as down without additional traffic configuration. It is possible
to skip the nginx ingress part and just use a DigitalOcean load
balancer but this again does require a good deal of setup and can be
more difficult then easy.
The suggestion to have a website with analytics (IP) and scalable was to setup a droplet with Nginx and setup a LoadBalancer to it. More specifically:
As for using a droplet this would be a normal website configuration
with Nginx as your webserver configured to serve content to your app.
You would have full access to your application and the Nginx logs on
the droplet itself. Putting a load balancer in front of this would
require additional configuration as load balancers do not pass the
x-forward header so the IP addresses of clients would not show up in
the logs by default. You would need to configured proxy protocol on
the load balancer and in your nginx configuration to be able to obtain
those IPs.
https://www.digitalocean.com/blog/load-balancers-now-support-proxy-protocol/
This is also a bit more complex unfortunately.
Hope it might save some time to someone
I am a kubernetes newbie, and no matter how much I read about it I cannot get my head around this issue.
I have a simple deployment , which is creating a pod with a not so complex app.
I know what an ingress and an ingress controller is doing ,but as far as I understand it is not required for me to expose my pod-app externally. Only a LoadBalancer service should be enough.
I do not have need of more than one rule for traffic routing.
Am I wrong about that?
Traditionally, you would create a LoadBalancer service for each service you want to expose externally. This can get rather expensive. Ingress gives you a way to route requests to services based on the request host or path, centralizing a number of services into a single entrypoint.
Also load balancer provisioning takes time and works only in supported cloud providers such as AWS, GCP etc.
One more thing to consider is the need of L4(TCP/UDP) layer routing because kubernetes Ingress API is primarily L7 layer but some of the ingress controllers such as traefik, nginx supports L4 layer(TCP/UDP) along with L7 layer(HTTP) routing.
So answer to your question is it depends based on your environment and use cases.
Ingress and IngressControllers are used for traffic routing at layer 7 i.e., if your backends talk L7 protocols like HTTP, GRPC etc. You can route requests based on request path to different backend services using Ingress.
If your app doesn't operate at Layer 7, you might not need an Ingress.
Another question you could ask yourself if your migrating your app from non-kubernetes environment to kuberneters is - are you using a reverse proxy like nginx already? If so, you might want to use Ingress. I say might because it is not necessary. You can achieve the same affect of using an Ingress by running the nginx container as a pod, writing the nginx.conf yourself and making it available externally(using a LoadBalancer service for example). Instead by using IngressController you need not maintain the nginx pod or write nginx.conf. You can instead express the same configuration as Ingress resource which is much simpler.
Ingress is needed if you want to expose your service to external. Especially for layer 7 in OSI model (HTTP transport). Ingress also provide the mechanism to enable TLS support in your load balancer. Traffic routing is controlled by rules defined on the Ingress resource. An Ingress can be configured to give Services externally-reachable URLs, load balance traffic, terminate SSL / TLS, and offer name based virtual hosting. An Ingress controller is responsible for fulfilling the Ingress, usually with a load balancer, though it may also configure your edge router or additional frontends to help handle the traffic.
By default Ingress controller depends on which kind of cloud provider you're using, or if you're using on premise you'll need to set it up based on what you need. In one cluster, you can create multiple Ingress controller as well. There's many kinds of Ingress controller, you can take a look on this article.
I think this article about Load Balancer and Ingress may also help.
my k8s master node has Public network IP, and worker node deploy in private net. worker node can connect to master but master cannot connect to worker node.
I have tested that can deploy a pod by kubectl, the pod running on worker node and master can watch pod status. but when I deploy a ingress, and access the ingress on master node, traffic cannot go to worker node.
I use flannel network.
I have tried use ssh tunnel, but it hard to management
I don't know if there are some suggests, thanks.
If you are deployed in a cloud environment, the most likely cause is incorrect firewall settings or route configurations. However, ingress configuration errors also may appear to look like infrastructure problems at times.
The Ingress will redirect your requests to the different services that it is registered with. The endpoint health is also monitored and requests will only be sent to active and healthy endpoints. My troubleshooting flow is as follows:
Hit an unregistered path on your url and check if you get the default backend response. If no, then your ingress controller may not be correctly set up (whether it be domain name, access rules, or just configuration). If yes, then your ingress controller should be correctly set up, and this is a problem with the Ingress definition or backend.
Try hitting your registered path on your url. If you get a 504 gateway timeout, then your endpoint is accepting the request, but not responding correctly. You can follow the target pod logs to figure out whether it is behaving properly.
If you get a 503 Service Unavailable, then your service might be down or deemed unhealthy by the ingress. In this case, you should definitely verify that your pods are running properly.
Check your nginx-ingress-controller logs to see how the requests are being redirected and what the internal responses are.
All your nodes and master should have communication with each other, without this you are going to have problems on cluster functionalities.
The ingress creates a load balancer pointing to your nodes machines.
Why your master cannot connect to your nodes?
Give a check on:
https://kubernetes.io/docs/concepts/architecture/master-node-communication/
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.