I have the zipkin deployment and service below as you can see zipkin is located under monitoring namespace the, i have an env variable called ZIPKIN_URL in each of my pods which are running under default namespace, this varibale takes this URL http://zipkin:9411/api/v2/spans but since zipkin is running in another namespace i tried this :
http://zipkin.monitoring.svc.cluster.local:9411/api/v2/spans
i also tried this format :
http://zipkin.monitoring:9411/api/v2/spans
but when i check the logs of my pods, i see connection refused exception
when i exec into one of my pods and try curl http://zipkin.tools.svc.cluster.local:9411/api/v2/spans
its shows me Mandatory parameter is missing: serviceNameroot
Here is zipkin resource :
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: zipkin
namespace: monitoring
spec:
template:
metadata:
labels:
app: zipkin
spec:
containers:
- name: zipkin
image: openzipkin/zipkin:2.19.3
ports:
- containerPort: 9411
---
apiVersion: v1
kind: Service
metadata:
name: zipkin
namespace: monitoring
spec:
selector:
app: zipkin
ports:
- name: http
port: 9411
protocol: TCP
type: ClusterIP
What you have is correct, your issue is likely not DNS. You can confirm by doing just a DNS lookup and comparing that to the IP of the Service.
Related
I am attaching the image of my application flow. Here the Gateway and other services are created using NestJS. The request for any API comes through the gateway.
The Gateway-pod and API-pod communicate using TCP protocol.
After deployment the Gateway is not able to discover any API pods.
I am attaching the YAML image file also for both Gateway & Pods.
Please do let me know what mistake I am doing in the YAML file.
**APPLICATION DIAGRAM**
Gateway YAML
apiVersion: apps/v1
kind: Deployment
metadata:
namespace: roushan
name: gateway-deployment
spec:
replicas: 1
selector:
matchLabels:
app: roushan-app
template:
metadata:
labels:
app: roushan-app
spec:
containers:
- name: gateway-container
image: nest-api-gateway:v8
ports:
- containerPort: 1000
apiVersion: v1
kind: Service
metadata:
namespace: roushan
name: gateway-svc
spec:
selector:
app: roushan-app
ports:
- name: gateway-svc-container
protocol: TCP
port: 80
targetPort: 1000
type: LoadBalancer
Pod YAML
apiVersion: apps/v1
kind: Deployment
metadata:
namespace: roushan
name: pod1-deployment
spec:
replicas: 1
selector:
matchLabels:
app: roushan-app
template:
metadata:
labels:
app: roushan-app
spec:
containers:
- name: pod1-container
image: nest-api-pod1:v2
ports:
- containerPort: 4000
apiVersion: v1
kind: Service
metadata:
namespace: roushan
name: pod1-srv
spec:
selector:
app: roushan-app
ports:
- name: pod1-svc-container
protocol: TCP
port: 80
targetPort: 4000
the gateway should be able to access the services by their DNS name. for example pod1-srv.svc.cluster.local, if this does not work you may need to look at the Kubernetes DNS setup.
I have not used AKS, they may use a different domain name for the cluster other than svc.cluster.local
YAML Points
Ideally, you should be keeping the different selectors across the deployment.
You are using the same selectors for both deployments. Gateway and application deployment.
Service will forward the traffic to deployment based on selectors and labels, this might redirect the service-2 request to POD-1.
Networking
You gateway service(Pods) connect to internal service by just service-name like : pod1-srv if in same namespaces.
if gateway and application in different namespaces you have to call each other like http://<servicename>.<namespace>.svc.cluster.local
Setup
I have a federated k8s cluster that each cluster has master and workers.
In a federation, each cluster has a different domain for accessing image registry. (e.g. myregistry-1, myregistry-2).
In other words, each cluster has its own registry.
Question
I don't want to change domain for each cluster. Basically, I would like to create a common endpoint that matches to each inner registry, which is internal to that cluster.
Example: Below deployment on all clusters.
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: nginx
spec:
replicas: 3
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: harbor.default:5000/nginx:1.14.2
ports:
- containerPort: 80
I tried to implement "Services without selectors" and created an endpoint and updated deployment.yaml but didn't work.
harbor.yaml
apiVersion: v1
kind: Service
metadata:
name: harbor-service
spec:
ports:
- protocol: TCP
port: 5000
targetPort: 5000
harbor-endpoint.yaml
apiVersion: v1
kind: Endpoints
metadata:
name: harbor-service
subsets:
- addresses:
- ip: <INTERNAL_IP_OF_REGISTRY>
ports:
- port: 5000
With kubernetes, I created an ingress with a service like these :
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
name: syntaxmap2
spec:
backend:
serviceName: testsvc
servicePort: 3000
The service testsvc is already created.
I created a frontend service like these :
apiVersion: v1
kind: Service
metadata:
name: syntaxmapfrontend
spec:
selector:
app: syntaxmap
tier: frontend
ports:
- protocol: "TCP"
port: 7000
targetPort: 7000
type: LoadBalancer
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: syntaxmapfrontend
spec:
selector:
matchLabels:
app: syntaxmap
tier: frontend
track: stable
replicas: 1
template:
metadata:
labels:
app: syntaxmap
tier: frontend
track: stable
spec:
containers:
- name: nginx
image: "gcr.io/google-samples/hello-frontend:1.0"
lifecycle:
preStop:
exec:
command: ["/usr/sbin/nginx","-s","quit"]
When I do these command :
kubectl describe ingress syntaxmap2
I have an Ip adress than i can put in my browser and I have an answer
But when I do these command :
kubctl describe service syntaxmapfrontend
I have an Ip adress with a port and when I try to connect to it with curl, I have a time out.
How can I connect to my kubernet frontend with curl ?
The service is accessible only from within the k8s cluster. You either need to change the type of address from ClusterIP to NodeIP, or use something like kubectl port-forward or kubefwd.
If you need more detailed advice, you'll need to post the output of those commands, or even better, show us how you created the objects.
I have found a way.
I write :
minikube service syntaxmapfrontend
And it open a browser with the right URL.
I have Kubernetes cluster, istio service mesh and MetalLB. Default namespace with istio-injection enabled.
I am trying to install Gravitee API gateway in my K8.
gravitee.yaml (deployment)
apiVersion: apps/v1
kind: Deployment
metadata:
name: gravitee-gateway-test
#labels:
#app: ratings
# version: v1
spec:
replicas: 1
selector:
matchLabels:
app: gravitee-gateway
#version: v1
template:
metadata:
labels:
app: gravitee-gateway
#version: v1
spec:
containers:
- name: gravitee-container
image: graviteeio/gateway:latest
ports:
- containerPort: 8082
gravity-service.yaml
apiVersion: v1
kind: Service
metadata:
name: gravitee-gateway-service
#labels:
#app: reviews
#service: reviews
spec:
ports:
- port: 9080
name: http
protocol: TCP
selector:
app: gravitee-gateway
type: LoadBalancer
Both ran with kubectl apply -f
MetalLB assigns a new IP address for Gravitee service 123.456.789.11 and port is 9080, when I logged to 123.456.789.11:9080, I get following error :
upstream connect error or disconnect/reset before headers. reset reason: connection failure
What am I missing here?
Referred :
503 upstream issue : istio
Random upstream error
We are facing an unexpected behavior in Kubernetes. When we are running the command:
kubectl apply -f my-service_deployment.yml
It's noticed that the associated existing service of the same pod getting deleted automatically. Also, we noticed that when we are applying the deployment file, instead of giving the output as the "deployment got configured" (as its already running), its showing output as "deployment created".. is some problem here?
Also sometimes we have noticed that the service is recreated with different timestamps than we created with different Ip.
What may be the reasons for this unexpected behavior of this service?
Note:- it's noticed that there is another pod and service running in the same cluster with pod name as "my-stage-my-service" and service name as my-stage-service-v1. will this have any impact?
Deployment file:-
apiVersion: apps/v1
kind: Deployment
metadata:
name: my-service
labels:
app: my-service
spec:
replicas: 1
selector:
matchLabels:
app: my-service
template:
metadata:
labels:
app: my-service
spec:
containers:
- name: my-service
image: myacr/myservice:v1-dev
ports:
- containerPort: 8080
imagePullSecrets:
- name: my-az-secret
Service file:
apiVersion: v1
kind: Service
metadata:
name: my-stage-service
spec:
selector:
app: my-service
ports:
- protocol: TCP
port: 8880
targetPort: 8080
type: LoadBalancer