We have a central monitoring cluster that monitors different k8s clusters (running various micro services)
Currently we’ve deployed prometheus using manifests but we plan to move to a prometheus operator.
My question is, is service discovery possible for prometheus in this kind of a set up? Will I be able to annotate my pods?
Of course, you'll be able to do service discovery with the Prometheus operator for Kubernetes.
However, it does not work as it does with a standalone Pormetheus server and the kubernetes_sd_config configuration.
With the operator, the service discovery works with a custom resource called ServiceMonitor. This resource works with label selector that target services with specific label. You can find an example here, in the official github page
Related
Got it:
running kubernetes cluster
installed by bitnami/kube-prometheus
added custom metrics for my services in kubernetes and they are visible in prometheus targets and service discovery
Problem:
I don't see any custom metrics for my services at http://localhost/graph and therefore I can not use any of the metrics to build graphs.
What is the search algorithm and solve this problem?
In some project there are scaling and orchestration implemented using technologies of a local cloud provider, with no Docker & Kubernetes. But the project has poor logging and monitoring, I'd like to instal Prometheus, Loki, and Grafana for metrics, logs, and visualisation respectively. Unfortunately, I've found no articles with instructions about using Prometheus without K8s.
But is it possible? If so, is it a good way? And how to do this? I also know that Prometheus & Loki can automatically detect services in the K8s to extract metrics and logs, but will the same work for a custom orchestration system?
Can't comment about Loki, but Prometheus is definitely doable.
Prometheus supports a number of service discovery mechanisms, k8s being just on of them. If you look at the list of options (the ones ending with _sd_config) you can see if your provider is there.
If it is not then a generic service discovery can be used. Maybe DNS-based discovery will work with your custom system? If not then with some glue code a file based service discovery will almost certainly work.
Yes, I'm running Prometheus, Loki etc. just fine in a AWS ECS cluster. It just requires a bit more configuration especially regarding service discovery (if you are not already using something like ECS Service Disovery or Hashicorp Consul)
I have two Kubernetes clusters representing dev and staging environments.
Separately, I am also deploying a custom DevOps dashboard which will be used to monitor these two clusters. On this dashboard I will need to show information such as:
RAM/HD Space/CPU usage of each deployed Pod in each environment
Pod health (as in if it has too many container restarts etc)
Pod uptime
All these stats have to be at a cluster level and also per namespace, preferably. As in, if I query a for a particular namespace, I have to get all the resource usages of that namespace.
So the webservice layer of my dashboard will send a service request to the master node of my respective cluster in order to fetch this information.
Another thing I need is to implement real time notifications in my DevOps dashboard. Every time a container fails, I need to catch that event and notify relevant personnel.
I have been reading around and two things that pop up a lot are Prometheus and Metric Server. Do I need both or will one do? I set up Prometheus on a local cluster but I can't find any endpoints it exposes which could be called by my dashboard service. I'm also trying to set up Prometheus AlertManager but so far it hasn't worked as expected. Trying to fix it now. Just wanted to check if these technologies have the capabilities to meet my requirements.
Thanks!
I don't know why you are considering your own custom monitoring system. Prometheus operator provides all the functionality that you mentioned.
You will end up only with your own grafana dashboard with all required information.
If you need custom notification you can set it up in Alertmanager creating correct prometheusrules.monitoring.coreos.com, you can find a lot of preconfigured prometheusrules in kubernetes-mixin
.
Using labels and namespaces in Alertmanager you can setup a correct route to notify person responsible for a given deployment.
Do I need both or will one do?, yes, you need both - Prometheus collects and aggregates metric when Metrick server exposes metrics from your cluster node for your Prometheus to scrape it.
If you have problems with Prometheus, Alertmanger and so on consider using helm chart as entrypoint.
Prometheus + Grafana are a pretty standard setup.
Installing kube-prometheus or prometheus-operator via helm will give you
Grafana, Alertmanager, node-exporter and kube-state-metrics by default and all be setup for kubernetes metrics.
Configure alertmanager to do something with the alerts. SMTP is usually the first thing setup but I would recommend some sort of event manager if this is a service people need to rely on.
Although a dashboard isn't part of your requirements, this will inform how you can connect into prometheus as a data source. There is docco on adding prometheus data source for grafana.
There are a number of prebuilt charts available to add to Grafana. There are some charts to visualise alertmanager too.
Your external service won't be querying the metrics directly with prometheus, in will be querying the collected data in prometheus stored inside your cluster. To access the API externally you will need to setup an external path to the prometheus service. This can be configured via an ingress controller in the helm deployment:
prometheus.ingress.enabled: true
You can do the same for the alertmanager API and grafana if needed.
alertmanager.ingress.enabled: true
grafana.ingress.enabled: true
You could use Grafana outside the cluster as your dashboard via the same prometheus ingress if it proves useful.
I am new to Kubernetes and trying to move from VM based services to Kubernetes.
Current approach,
Have multiple VM's and running services on each VM. Services are running on multiple VM's and have VIP in front of them. Clients will be accessing VIP and VIP will be doing round robin on available services.
I read ISTIO and ingress and hope, the same thing can be done using ISTIO. I have setup a local minikube cluster and exploring all the use cases. I was able to deploy my service with scaling factor 2. Now, I would like to access my service using VIP. I was not sure how to create VIP and expose to other service in the Kubernetes cluster and services running outside the Kubernetes cluster? Can i use the same existing VIP? Or, Do i need to do any extra setting create a VIP in Kubenetes with any service name?
Thanks
Please note that Istio is an additional layer on top of other frameworks, including Kubernetes. In your case you should port your application to Kubernetes first, and then add Istio if needed.
Porting to Kubernetes:
Instead of a VIP, you define a Kubernetes service. You change the code or configure your microservices to use the defined Kubernetes services instead of the VIPs.
To access your services from the outside, you define a Kubernetes Ingress.
This probably should be enough to make your application run on Kubernetes.
Once you ported your application to Kubernetes, you can add Istio, see Istio Quick Start Guide. Istio can provide you advanced routing, logging and monitoring, policy enforcement, traffic encryption between services, and also support for various microservices patterns. See more at istio.io.
We run our stack on the Google Cloud Platform (hosted Kubernetes, GKE) and have a Consul cluster running outside of K8s (regular GCE instances).
Several services running in K8s use Consul, mostly for it's CP K/V Store and advanced locking, not so much for service discovery so far.
We recently ran into some issues with using the Consul service discovery from within K8s. Right now our apps talk directly to the Consul Servers to register and unregister services they provide.
This is not recommended best-practice, usually Consul clients (i.e. apps using Consul) should talk to the local Consul agent. In our setup there are no local Consul agents.
My Question: Should we run local Consul agents as sidekick containers in each pod?
IMHO this would be a huge waste of ressources, but it would match the Consul best-practies better.
I tried searching on Google, but all posts about Consul and Kubernetes talk about running Consul in K8s, which is not what I want to do.
As the official Consul Helm chart and the documentation suggests the standard approach is to run a DaemonSet of Consul clients and then use a connect-side-car injector to inject sidecars into your node simply by providing an annotation of the pod spec. This should handle all of the boilerplate and will be inline with best practices.
Consul: Connect Sidecar; https://www.consul.io/docs/platform/k8s/connect.html