VMware Instances not able to reach to management server

[vishesh92]

ISSUE TYPE

• Bug Report

COMPONENT NAME

VR

CLOUDSTACK VERSION

Checked in 4.18 & 4.19

CONFIGURATION

OS / ENVIRONMENT

CloudStack with VMWare

SUMMARY

Management server is not reachable from the instances. This causes issues especially with CKS not being able to create load balancer.

STEPS TO REPRODUCE

1. Create an isolated network
2. Launch an instance
3. Try to connect to the management server from the instance

EXPECTED RESULTS

Able to reach the management server from the instance

ACTUAL RESULTS

Not able to reach the management server from the instance

[weizhouapache]

@vishesh92
I have updated the title to emphysize this issue happens with VMware only

as Vishesh said, this causes CKS control nodes are not able to create lb rules as they cannot connect to cloudstack management server

[rajujith]

We could add a policy routing rule in VR to forward the traffic to the management server/ enpoint.url from instances via public interface. CC @vishesh92 @weizhouapache

[DaanHoogland]

@rajujith ,
Why do we want VMs be able to reach the MS? they could go through the north net if needed. It does not seem like a good idea to route them directly. I understand that it would be convenient for CKS nodes, but it does not seem like a good idea to me.
cc @weizhouapache @vishesh92

[weizhouapache]

@rajujith , Why do we want VMs be able to reach the MS? they could go through the north net if needed. It does not seem like a good idea to route them directly. I understand that it would be convenient for CKS nodes, but it does not seem like a good idea to me. cc @weizhouapache @vishesh92

@DaanHoogland
I agree we/users should have better network design.
the VM should reach the MS via public network, not private network.

I think we could consider it as a known limitation for CKS on vmware.

[rajujith]

@rajujith , Why do we want VMs be able to reach the MS? they could go through the north net if needed. It does not seem like a good idea to route them directly. I understand that it would be convenient for CKS nodes, but it does not seem like a good idea to me. cc @weizhouapache @vishesh92

@DaanHoogland, consider the management server URL public/intranet. It is expected that all intended users, including guest instances, should be able to access it from their client devices. In this specific case, the client is CKS. If there is a use case to allow access only from the CKS nodes but not regular guest instances even that could be implemented. The traffic traversal is CKS node -> VR guest interface -> VR public interface -> other hopes in the path -> management server public interface directly or via LB. Since the guest instance traffic is not traversing the management networks I believe it is a regular traffic that can be allowed.

[kiranchavala]

@DaanHoogland

To provide further context on this

1. Once a Kubernetes cluster is deployed on the vmware by cloudstack

2. End user downloads the kubernetes config to interact with the kubernetes cluster via the kubectl tool

3. End user populates the kubeconfig file so that kubectl tool can interact with the cluster

vi .kube/config

4. Check the status of the cluster and nodes

kubectl get nodes
NAME                       STATUS   ROLES           AGE     VERSION
test-control-19377251026   Ready    control-plane   4d22h   v1.28.4
test-node-19377261815      Ready    <none>          4d22h   v1.28.4

5. Deploy a sample application (example: nginx) on kubernetes cluster

kubectl apply -f nginx.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 2 # tells deployment to run 2 pods matching the template
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.14.2
        ports:
        - containerPort: 80

6. Check the application status

 kubectl get pods
NAME                                READY   STATUS    RESTARTS   AGE
nginx-deployment-86dcfdf4c6-fvjxp   1/1     Running   0          66m
nginx-deployment-86dcfdf4c6-jqjxw   1/1     Running   0          66m

7. Now end user want to access the application via public IP ( public IP range ) which is provided by cloudstack

kubectl expose deploy/nginx-deployment --port=80 --type=LoadBalancer

8. Now check the external public IP , it will be struck in pending state

k get svc
NAME               TYPE           CLUSTER-IP       EXTERNAL-IP   PORT(S)        AGE
kubernetes         ClusterIP      10.96.0.1        <none>        443/TCP        4d22h
nginx-deployment   LoadBalancer   10.104.200.145   <pending>     80:32333/TCP   66m

9. This is because the controller pods( cloud-controller-manager and kube-controller-manager)

which are responsible for assigning a public IP address to the application fails

kube-system            kube-controller-manager-test-control-19377251026   1/1     Running   79 (6h15m ago)   4d22h   172.30.1.109   test-control-19377251026
kube-system            cloud-controller-manager-574bcb86c-9fcgd           1/1     Running   77 (8h ago)    5d1h

10. On checking the Logs of the cloud-controller pod, we can see a timeout issue.

k logs -f cloud-controller-manager-574bcb86c-9fcgd -n kube-system

47DXsoV%2BOnK945EvKkfLmLj4tU%3D: dial tcp 10.1.35.76:8080: i/o timeout, and error by node name: error retrieving node addresses: Get http://10.1.35.76:8080/client/api?apiKey=m8GvJ-HIcVY9XurofyAvOLn6mV7aAURljtgpCVH13b5O48ej_ewMNjNo32iKe64oeSuYrzI_gEgg7JCTo_UjPA&command=listVirtualMachines&name=test-control-19377251026&response=json&signature=N6Ykg6Es%2BQWJYXIQ5KKXjyAHoiI%3D: dial tcp 10.1.35.76:8080: i/o timeout
E1204 07:44:13.663811       1 controller.go:244] error processing service kube-system/nginx-lb (will retry): failed to ensure load balancer: error retrieving load balancer rules: Get http://10.1.35.76:8080/client/api?apiKey=m8GvJ-HIcVY9XurofyAvOLn6mV7aAURljtgpCVH13b5O48ej_ewMNjNo32iKe64oeSuYrzI_gEgg7JCTo_UjPA&command=listLoadBalancerRules&keyword=ab9e4156d8f724ccfa61f379a8aaa0a6&listall=true&response=json&signature=MYL8q14GpEp5QxnRDg4nRXnkhQg%3D: dial tcp 10.1.35.76:8080: i/o timeout
I1204 07:44:13.664131       1 event.go:278] Event(v1.ObjectReference{Kind:"Service", Namespace:"kube-system", Name:"nginx-lb", UID:"b9e4156d-8f72-4ccf-a61f-379a8aaa0a63", APIVersion:"v1", ResourceVersion:"937", FieldPath:""}): type: 'Warning' reason: 'SyncLoadBalancerFailed' Error syncing load balancer: failed to ensure load balancer: error retrieving load balancer rules: Get http://10.1.35.76:8080/client/api?apiKey=m8GvJ-HIcVY9XurofyAvOLn6mV7aAURljtgpCVH13b5O48ej_ewMNjNo32iKe64oeSuYrzI_gEgg7JCTo_UjPA&command=listLoadBalancerRules&keyword=ab9e4156d8f724ccfa61f379a8aaa0a6&listall=true&response=json&signature=MYL8q14GpEp5QxnRDg4nRXnkhQg%3D: dial tcp 10.1.35.76:8080: i/o timeout
I1204 07:44:13.665040       1 event.go:278] Event(v1.ObjectReference{Kind:"Service", Namespace:"default", Name:"nginx-deployment", UID:"efa6bff6-3d27-411f-a5be-2a94f7416df7", APIVersion:"v1", ResourceVersion:"995877", FieldPath:""}): type: 'Normal' reason: 'EnsuringLoadBalancer' Ensuring load balancer
E1204 07:44:39.309010       1 node_controller.go:237] error retrieving instance ID: Get http://10.1.35.76:8080/client/api?apiKey=m8GvJ-HIcVY9XurofyAvOLn6mV7aAURljtgpCVH13b5O48ej_ewMNjNo32iKe64oeSuYrzI_gEgg7JCTo_UjPA&command=listVirtualMachines&name=test-node-19377261815&response=json&signature=1ONErKvq5OZxjpR26hzPmd8PLtY%3D: dial tcp 10.1.35.76:8080: i/o timeout
E1204 07:44:43.665211       1 controller.go:244] error processing service default/nginx-deployment (will retry): failed to ensure load balancer: error retrieving load balancer rules: Get http://10.1.35.76:8080/client/api?apiKey=m8GvJ-HIcVY9XurofyAvOLn6mV7aAURljtgpCVH13b5O48ej_ewMNjNo32iKe64oeSuYrzI_gEgg7JCTo_UjPA&command=listLoadBalancerRules&keyword=aefa6bff63d27411fa5be2a94f7416df&listall=true&response=json&signature=AHQ1nikqf3Vi7ISV9zwO%2FuxgjgU%3D: dial tcp 10.1.35.76:8080: i/o timeout
I1204 07:44:43.665448       1 event.go:278] Event(v1.ObjectReference{Kind:"Service", Namespace:"default", Name:"nginx-deployment", UID:"efa6bff6-3d27-411f-a5be-2a94f7416df7", APIVersion:"v1", ResourceVersion:"995877", FieldPath:""}): type: 'Warning' reason: 'SyncLoadBalancerFailed' Error syncing load balancer: failed to ensure load balancer: error retrieving load balancer rules: Get http://10.1.35.76:8080/client/api?apiKey=m8GvJ-HIcVY9XurofyAvOLn6mV7aAURljtgpCVH13b5O48ej_ewMNjNo32iKe64oeSuYrzI_gEgg7JCTo_UjPA&command=listLoadBalancerRules&keyword=aefa6bff63d27411fa5be2a94f7416df&listall=true&response=json&signature=AHQ1nikqf3Vi7ISV9zwO%2FuxgjgU%3D: dial tcp 10.1.35.76:8080: i/o timeout
E1204 07:45:39.310773       1 node_controller.go:245] Error getting node addresses for node "test-node-19377261815": error fetching node by provider ID: error retrieving node addresses: Get http://10.1.35.76:8080/client/api?apiKey=m8GvJ-HIcVY9XurofyAvOLn6mV7aAURljtgpCVH13b5O48ej_ewMNjNo32iKe64oeSuYrzI_gEgg7JCTo_UjPA&command=listVirtualMachines&id=&response=json&signature=547DXsoV%2BOnK945EvKkfLmLj4tU%3D: dial tcp 10.1.35.76:8080: i/o timeout, and error by node name: error retrieving node addresses: Get http://10.1.35.76:8080/client/api?apiKey=m8GvJ-HIcVY9XurofyAvOLn6mV7aAURljtgpCVH13b5O48ej_ewMNjNo32iKe64oeSuYrzI_gEgg7JCTo_UjPA&command=listVirtualMachines&name=test-node-19377261815&response=json&signature=1ONErKvq5OZxjpR26hzPmd8PLtY%3D: dial tcp 10.1.35.76:8080: i/o timeout
E1204 07:46:20.106490       1 controller.go:719] failed to check if load balancer exists for service kube-system/nginx-lb: error retrieving load balancer rules: Get http://10.1.35.76:8080/client/api?apiKey=m8GvJ-HIcVY9XurofyAvOLn6mV7aAURljtgpCVH13b5O48ej_ewMNjNo32iKe64oeSuYrzI_gEgg7JCTo_UjPA&command=listLoadBalancerRules&keyword=ab9e4156d8f724ccfa61f379a8aaa0a6&listall=true&response=json&signature=MYL8q14GpEp5QxnRDg4nRXnkhQg%3D: dial tcp 10.1.35.76:8080: i/o timeout
E1204 07:46:20.106727       1 controller.go:685] failed to update load balancer hosts for service kube-system/nginx-lb: error retrieving load balancer rules: Get http://10.1.35.76:8080/client/api?apiKey=m8GvJ-HIcVY9XurofyAvOLn6mV7aAURljtgpCVH13b5O48ej_ewMNjNo32iKe64oeSuYrzI_gEgg7JCTo_UjPA&command=listLoadBalancerRules&keyword=ab9e4156d8f724ccfa61f379a8aaa0a6&listall=true&response=json&signature=MYL8q14GpEp5QxnRDg4nRXnkhQg%3D: dial tcp 10.1.35.76:8080: i/o timeout
I1204 07:46:20.107496       1 event.go:278] Event(v1.ObjectReference{Kind:"Service", Namespace:"kube-system", Name:"nginx-lb", UID:"b9e4156d-8f72-4ccf-a61f-379a8aaa0a63", APIVersion:"v1", ResourceVersion:"937", FieldPath:""}): type: 'Warning' reason: 'UpdateLoadBalancerFailed' Error updating load balancer with new hosts map[test-control-19377251026:{} test-node-19377261815:{}]: error retrieving load balancer rules: Get http://10.1.35.76:8080/client/api?apiKey=m8GvJ-HIcVY9XurofyAvOLn6mV7aAURljtgpCVH13b5O48ej_ewMNjNo32iKe64oeSuYrzI_gEgg7JCTo_UjPA&command=listLoadBalancerRules&keyword=ab9e4156d8f724ccfa61f379a8aaa0a6&listall=true&response=json&signature=MYL8q14GpEp5QxnRDg4nRXnkhQg%3D: dial tcp 10.1.35.76:8080: i/o timeout

So basically a user on a vmware is unable to access the Kubernetes application via the kubernetes loadbalancer service

The workaround is expose the application via NodePort service

Follow steps 1 to 6

11. Expose the application via node-port

kubectl  expose deploy/nginx-deployment --port=80 --type=Nodeport 

NAME                TYPE           CLUSTER-IP       EXTERNAL-IP   PORT(S)        AGE
kubernetes          ClusterIP      10.96.0.1        <none>        443/TCP        5d1h
nginx-deployment2   NodePort       10.103.111.85    <none>        80:32014/TCP   4s

12. Navigate to network and acquire a public IP

13. Allow the firewall port 80 on the public IP address

14. Add a loadbalcner rule mentioning the private node port

15. Add the kubernetes node

16. Access the application on the manually acquired public IP on port 80

I think for now we can document this workaround for CKS deployments on vmware and mention the loadbalancer service is not supported on vmware

cc @rajujith @vishesh92 @weizhouapache

Ref

https://kubernetes.io/docs/tutorials/kubernetes-basics/expose/expose-intro/
https://kubernetes.io/docs/concepts/services-networking/

[weizhouapache]

thanks @kiranchavala providing the workaround

I agree we could document it for now.

We will work on static routes improvement and policy-based routes for next release.
With it, user vms could reach the mgmt server by adding a new route via public network.
cc @rajujith @DaanHoogland @alexandremattioli