Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. I would like to avoid using type: "LoadBalancer" for a certain Kubernetes Service, but still to be able to publish it on the Internet. None of the above helped me reach my application using the Kubernetes Service with an externalIPs configuration.
If you don't want to use a LoadBalancer service, other options for exposing your service publicly are:. Create your service with type set to NodePortand Kubernetes will allocate a port on all of your node VMs on which your service will be exposed docs. The cluster endpoint won't work for this because that is only the IP of your Kubernetes master. The public IP of another LoadBalancer service won't work because the LoadBalancer is only configured to route the port of that original service.
I'd expect the node IP to work, but it may conflict if your service port is a privileged port. There are a few idiomatic ways to expose a service externally in Kubernetes see note 1 :.
You can use node selectors or affinity or other tools to influence this choice. Learn more.
Asked 3 years, 10 months ago. Active 28 days ago. Viewed 3k times. Gabriel Petrovay Gabriel Petrovay Active Oldest Votes. If you don't want to use a LoadBalancer service, other options for exposing your service publicly are: Type NodePort Create your service with type set to NodePortand Kubernetes will allocate a port on all of your node VMs on which your service will be exposed docs.
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Is it possible to use the Ingress Controller function in Kubernetes without a load balancer in Digital Ocean. Is there any other mechanism to allow a domain name to map to a Kubernetes service; for instance if I host two WordPress sites on a Kubernetes cluster:.
How does a domain name map to the container port without explicitly entering the port number. DNS doesn't support adding port numbers, you need an ingress controller which essentially acts like a reverse proxy to do this.[ Kube 65.5 ] Kubespray - Configuring external Load Balancer
If you install the digital ocean cloud controller manager you'll be able to provision loadbalancers using services with type LoadBalancer. This then becomes the ingress into your cluster, and you only have a single LoadBalancer, which keeps costs down. Learn more. Asked 1 year, 9 months ago. Active 1 year, 8 months ago.
Viewed 2k times. Any help is appreciated. Rutnet Rutnet 5 5 silver badges 18 18 bronze badges. Active Oldest Votes. Is it possible to point both domain to the ingress controller and let ingress route base on hostname to the correct pod?
Can that eliminate the need of the lb to save cost? It should be possible to map a NodePort external ip to 80 or without going through a load balancer. DatTran i had it setup with a NodePort on the Droplet. Than the Droplet got restarted and changed IP.
That should do the trick. See stackoverflow.For all but the simplest Kubernetes configurations, efficiently distributing client requests across multiple clusters should be a priority.
A load balancer routes requests to clusters in order to optimize performance and ensure the reliability of your application.
With a load balancer, the demands on your application are shared equally across clusters so that all available resources are utilized and no single cluster is overburdened. This level of abstraction insulates the client from the containers themselves. Pods can be created and destroyed by Kubernetes automatically, and they are not expected to be persistent.
Since every new pod is assigned a new IP address, IP addresses for pods are not stable; therefore, direct communication between pods is not generally possible. However, services have their own IP addresses which are relatively stable; thus, a request from an external resource is made to a service rather than a pod, and the service then dispatches the request to an available pod.
An external load balancer will apply logic that ensures the optimal distribution of these requests. In order to create one, your clusters must be hosted by a cloud provider or an environment which supports external load balancers and is configured with the correct cloud load balancer provider package.
You will also need to install and configure the kubectl command-line tool to communicate with your cluster. This provides an externally-accessible IP address that sends traffic to the correct port on your cluster nodes to be accessed by the external load balancer provided by your cloud provider.
Both of these commands will expose the name, cluster IP address, external IP address, port, and age of your load balancer s. Sometimes, a load balancer is not provisioned for a cluster in order to efficiently manage traffic leading into it, but simply to expose it to the internet. Kubernetes will then choose an available port to open on all your nodes so that any traffic sent to this port passes through to your application.
On the other hand, if you are trying to optimize traffic to multiple services, you may consider a more robust method than the LoadBalancer type suggested above. You will be charged by your cloud provider for each service that requires an external load balancer, as well as for each IP address provisioned for your balancers. Another strategy is to use Ingress, which allows you to expose multiple services under the same IP address.
Ingress runs as a controller in a specialized Kubernetes pod that executes a set of rules governing traffic. With Ingress, you only pay for one load balancer.
There are many types of Ingress controllers and your implementation will depend on your environment, but it is safe to say that deploying Ingress requires a more complicated configuration than the process given above. Thus, you must weigh the potential cost savings against the increased complexity.
gRPC Load Balancing on Kubernetes without Tears
With your load balancer configured, you can trust that requests to your services will be dispatched efficiently, ensuring smoother performance and enabling you to handle greater loads. The Sumo Logic Kubernetes App provides visibility on all your nodes, allowing you to monitor and troubleshoot load balancing as well as myriad other metrics to track the health of your clusters.
You can track the loads being placed on each service to verify that resources are being shared evenly, and you can also monitor the load balancing service itself from a series of easy-to-understand dashboards. If your application must handle an unpredictable number of requests, a load balancer is essential for ensuring reliable performance without the cost of over-provisioning.
Depending on the number of services you need to route traffic to, as well as the level of complexity you are willing to accept, you might choose to use Ingress or the external load balancing service offered by your cloud provider. Regardless of how you implement your load balancing, monitoring its performance through the Sumo Logic Kubernetes App will allow you to measure its benefits and quickly react when it is not operating as it should.
What is Load Balancing on Kubernetes? External Load Balancer Alternatives Sometimes, a load balancer is not provisioned for a cluster in order to efficiently manage traffic leading into it, but simply to expose it to the internet. Monitoring your Load Balancer With your load balancer configured, you can trust that requests to your services will be dispatched efficiently, ensuring smoother performance and enabling you to handle greater loads.
But, when ingress was created, it doesn't show its address and it seems not running properly, I cannot get anything from port 80 on curl :. Learn more.
Load-Balancing in Kubernetes
How to setup kubernetes nginx ingress without load balancer? Ask Question. Asked 1 year, 2 months ago. Active 1 year, 2 months ago.
Viewed times. Justinus Hermawan Justinus Hermawan 1 1 gold badge 10 10 silver badges 28 28 bronze badges. It would be better if you provide enough info for your question i.
Then it is easy to answer to your question. Shudipta is right, we need some more information. Also any more steps you have done? You mention ingress controller, did you deploy it at all? Active Oldest Votes. If you try to define path? Didier Didier 31 2 2 bronze badges.Edit This Page.
When creating a service, you have the option of automatically creating a cloud network load balancer. This provides an externally-accessible IP address that sends traffic to the correct port on your cluster nodes provided your cluster runs in a supported environment and is configured with the correct cloud load balancer provider package.
For information on provisioning and using an Ingress resource that can give services externally-reachable URLs, load balance the traffic, terminate SSL etc. You need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. If you do not already have a cluster, you can create one by using Minikubeor you can use one of these Kubernetes playgrounds:.
To create an external load balancer, add the following line to your service configuration file :. This command creates a new service using the same selectors as the referenced resource in the case of the example above, a replication controller named example. For more information, including optional flags, refer to the kubectl expose reference. You can find the IP address created for your service by getting the service information through kubectl :. Due to the implementation of this feature, the source IP seen in the target container is not the original source IP of the client.
Setting externalTrafficPolicy to Local in the Service configuration file activates this feature. In usual case, the correlating load balancer resources in cloud provider should be cleaned up soon after a LoadBalancer type Service is deleted. But it is known that there are various corner cases where cloud resources are orphaned after the associated Service is deleted. Finalizer Protection for Service LoadBalancers was introduced to prevent this from happening. By using finalizers, a Service resource will never be deleted until the correlating load balancer resources are also deleted.
Specifically, if a Service has type LoadBalancer, the service controller will attach a finalizer named service. The finalizer will only be removed after the load balancer resource is cleaned up.
This prevents dangling load balancer resources even in corner cases such as the service controller crashing.
It is important to note that the datapath for this functionality is provided by a load balancer external to the Kubernetes cluster. When the Service type is set to LoadBalancer, Kubernetes provides functionality equivalent to type equals ClusterIP to pods within the cluster and extends it by programming the external to Kubernetes load balancer with entries for the Kubernetes pods. The Kubernetes service controller automates the creation of the external load balancer, health checks if neededfirewall rules if needed and retrieves the external IP allocated by the cloud provider and populates it in the service object.
This was not an issue with the old LB kube-proxy rules which would correctly balance across all endpoints.
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Once the external load balancers provide weights, this functionality can be added to the LB programming path. Future Work: No support for weights is provided for the 1. Internal pod to pod traffic should behave similar to ClusterIP services, with equal probability across all pods. Thanks for the feedback. If you have a specific, answerable question about how to use Kubernetes, ask it on Stack Overflow. Open an issue in the GitHub repo if you want to report a problem or suggest an improvement.
Note: This feature is only available for cloud providers or environments which support external load balancers. Note: If you are running your service on Minikube, you can find the assigned IP address and port with:. Stable versions of features will appear in released software for many subsequent versions.
Create an Issue Edit This Page.In this blog post, we describe why this happens, and how you can easily fix it by adding gRPC load balancing to any Kubernetes app with Linkerda CNCF service mesh and service sidecar.
Normally, this is great, as it reduces the overhead of connection management. All requests will get pinned to a single destination pod, as shown below:. The client makes a request, e. While that request-response cycle is happening, no other requests can be issued on that connection. Usually, we want lots of requests happening in parallel. Now back to gRPC. How do we accomplish this? There are a couple options. First, our application code could manually maintain its own load balancing pool of destinations, and we could configure our gRPC client to use this load balancing pool.
This approach gives us the most control, but it can be very complex in environments like Kubernetes where the pool changes over time as Kubernetes reschedules pods. Our application would have to watch the Kubernetes API and keep itself up to date with the pods. Alternatively, in Kubernetes, we could deploy our app as headless services. If our gRPC client is sufficiently advanced, it can automatically maintain the load balancing pool from those DNS entries.
Most relevant to our purposes, Linkerd also functions as a service sidecarwhere it can be applied to a single service—even without cluster-wide permissions. What this means is that when we add Linkerd to our service, it adds a tiny, ultra-fast proxy to each pod, and these proxies watch the Kubernetes API and do gRPC load balancing automatically.
Our deployment then looks like this:. Using Linkerd has a couple advantages. First, it works with services written in any language, with any gRPC client, and any deployment model headless or not. This means that everything will just work.
Not only does Linkerd maintain a watch on the Kubernetes API and automatically update the load balancing pool as pods get rescheduled, Linkerd uses an exponentially-weighted moving average of response latencies to automatically send requests to the fastest pods.
If one pod is slowing down, even momentarily, Linkerd will shift traffic away from it. This can reduce end-to-end tail latencies. Linkerd is very easy to try.Edit This Page. An abstract way to expose an application running on a set of Pods The smallest and simplest Kubernetes object.
A Pod represents a set of running containers on your cluster. Kubernetes Pods The smallest and simplest Kubernetes object.
They are born and when they die, they are not resurrected. Each Pod gets its own IP address, however in a Deployment, the set of Pods running in one moment in time could be different from the set of Pods running that application a moment later.
In Kubernetes, a Service is an abstraction which defines a logical set of Pods and a policy by which to access them sometimes this pattern is called a micro-service. The set of Pods targeted by a Service is usually determined by a selector Allows users to filter a list of resources based on labels. For example, consider a stateless image-processing backend which is running with 3 replicas.
Those replicas are fungible—frontends do not care which backend they use. While the actual Pods that compose the backend set may change, the frontend clients should not need to be aware of that, nor should they need to keep track of the set of backends themselves. For non-native applications, Kubernetes offers ways to place a network port or load balancer in between your application and the backend Pods. The name of a Service object must be a valid DNS label name. Port definitions in Pods have names, and you can reference these names in the targetPort attribute of a Service.
This works even if there is a mixture of Pods in the Service using a single configured name, with the same network protocol available via different port numbers. This offers a lot of flexibility for deploying and evolving your Services. For example, you can change the port numbers that Pods expose in the next version of your backend software, without breaking clients. The default protocol for Services is TCP; you can also use any other supported protocol.
As many Services need to expose more than one port, Kubernetes supports multiple port definitions on a Service object. Each port definition can have the same protocolor a different one. Services most commonly abstract access to Kubernetes Pods, but they can also abstract other kinds of backends.
For example:. Because this Service has no selector, the corresponding Endpoint object is not created automatically. The name of the Endpoints object must be a valid DNS subdomain name.
The endpoint IPs must not be: loopback Endpoint IP addresses cannot be the cluster IPs of other Kubernetes Services, because kube-proxy kube-proxy is a network proxy that runs on each node in the cluster.
Accessing a Service without a selector works the same as if it had a selector. In the example above, traffic is routed to the single endpoint defined in the YAML: For more information, see the ExternalName section later in this document. Although conceptually quite similar to Endpoints, EndpointSlices allow for distributing network endpoints across multiple resources.
EndpointSlices provide additional attributes and functionality which is described in detail in EndpointSlices. The AppProtocol field provides a way to specify an application protocol to be used for each Service port. As an alpha feature, this field is not enabled by default. To use this field, enable the ServiceAppProtocol feature gate.