minikube ip is not reachable - kubernetes

Question

I have created one service called fleetman-webapp:
apiVersion: v1
kind: Service
metadata:
name: fleetman-webapp
spec:
selector:
app: webapp
ports:
- name: http
port: 80
nodePort: 30080
type: NodePort
also, a pod named webapp:
apiVersion: v1
kind: Pod
metadata:
name: webapp
labels:
app: webapp
spec:
containers:
- name: webapp
image: richardchesterwood/k8s-fleetman-webapp-angular:release0
I have checked the minikube ip:
192.168.99.102
But when I type in the browser 192.168.99.102:30080, the webapp is not reachable:
Please note that I use Ubuntu latest version. I have verified furthermore if proxies and firewalls are active:
cat /etc/environment:
PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games"
iptables -L:
Chain INPUT (policy ACCEPT)
target prot opt source destination
Chain FORWARD (policy DROP)
target prot opt source destination
DOCKER-USER all -- anywhere anywhere
DOCKER-ISOLATION-STAGE-1 all -- anywhere anywhere
ACCEPT all -- anywhere anywhere ctstate RELATED,ESTABLISHED
DOCKER all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
Chain DOCKER (1 references)
target prot opt source destination
Chain DOCKER-ISOLATION-STAGE-1 (1 references)
target prot opt source destination
DOCKER-ISOLATION-STAGE-2 all -- anywhere anywhere
RETURN all -- anywhere anywhere
Chain DOCKER-ISOLATION-STAGE-2 (1 references)
target prot opt source destination
DROP all -- anywhere anywhere
RETURN all -- anywhere anywhere
Chain DOCKER-USER (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
I have also disabled ufw in Ubuntu, but no success, the url 192.168.99.102:30080 .
Would you help me please ? thanks in advance for your answer.

Answer 1

Even though, you are exposing port 30080 via NodePort in minikube, minikube will still not expose it because it will use its own external port to listen to this service. Minikube tunnels the service to expose to the outer world. To find out that exposed port:
minikube service $SERVICE_NAME
so, in your case
minikube service fleetman-webapp

Answer 2

There are a lot of different hypervisors which can work with minikube. Choosing one will be highly dependent on variables like operating system. Some of them are:
Virtualbox
Hyper-V
VMware Fusion
KVM2
Hyperkit
"Docker (--vm-driver=none)" (see the quotes)
There is official documentation talking about it: Kubernetes.io: Minikube: Specifying the vm driver
Choosing Hypervisor will affect how the minikube will behave.
Focusing on:
Docker: --vm-driver=none
Virtualbox: --vm-driver=virtualbox
Docker
Official documentation sums it up:
Minikube also supports a --vm-driver=none option that runs the Kubernetes components on the host and not in a VM. Using this driver requires Docker and a Linux environment but not a hypervisor.
-- Kubernetes.io: Install minikube: Install a hypervisor
The output of command$ sudo minikube ip will show IP address of a host machine.
Service object type of NodePort will be available with IP_ADDRESS_OF_HOST:NODEPORT_PORT.
Following with command: $ kubectl get nodes -o wide:
NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME
K8S Ready master 95s v1.17.3 192.168.0.114 <none> Ubuntu 18.04.4 LTS 5.3.0-28-generic docker://19.3.8
Please take a specific look on:
INTERNAL-IP
192.168.0.114
It's the same IP address as a host it's working on. You can (for example) curl pods without any restrictions. Please consider reading the article in included citing:
Caution: The none VM driver can result in security and data loss issues. Before using --vm-driver=none, consult this documentation for more information.
You can check what was exposed with command:
$ sudo netstat -tulpn
Virtualbox
Creating a minikube instance with --vm-driver=virtualbox will create a virtual machine with Virtualbox as host.
Virtual machine created with this kind of --vm-driver will have 2 network interfaces provided below:
NAT
Host-only adapter
What is important is that your minikube instance will be accessible by Host-only adapter.
Host-only networking. This can be used to create a network containing the host and a set of virtual machines, without the need for the host's physical network interface. Instead, a virtual network interface, similar to a loopback interface, is created on the host, providing connectivity among virtual machines and the host.
-- Virtualbox.org: Virtual networking
For example:
minikube host-only adapter will have an address: 192.168.99.103
Your host-only adapter will have an address: 192.168.99.1
They must be different!
If you are having issues with connecting to this adapter please check:
If minikube's host-only adapter address is responding to ping when minikube start completed successfully.
Your host-only adapter is present in your network configuration by issuing either:
ip a
ifconfig
Your host-only adapter address is in range of your minikube instance (subnet)
From my experience reboot/recreation of this adapter worked all the time if something wasn't right.
The output of command$ sudo minikube ip will show IP address of a Host-only adapter.
Following with command: $ kubectl get nodes -o wide:
NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME
m01 Ready master 29m v1.17.3 192.168.99.103 <none> Buildroot 2019.02.9 4.19.94 docker://19.3.6
Please take a specific look once more on INTERNAL-IP and ip address associated with it.
Service object type of NodePort will be available with:
IP_ADDRESS_OF_HOST_ONLY_ADAPTER:NODEPORT_PORT.
I recreated your Deployment and Service attached to it and it worked in both --vm-driver=none and --vm-driver=virtualbox cases.
Please let me know if you have any questions in this topic.

Answer 3

I have had the same issue and have been trying to solve that for the last 2 days I have tried to install ingress addon:
minikube addons enable ingress
and also tried to run :
minikube tunnel
looked for a way to allow the host machine to access the container IP address but apparently couldn't find a way to do that.
If you run minikube on docker:
minikube start --driver=docker
you won't be able to access the minikube IP from your host machine since the minikube container's IP address would by accessible through DockerDesktopVM but not from your host machine.
You could run minikube on another driver such as VirtualBox or Hyperv, and that might help.
minikube start --driver=hyperv
minikube start --driver=virtualbox
Read more about the minikube drivers
In fact, that's really annoying if you don't have enough resources on your computer to run both the Docker desktop VM and the minikube VM at the same time and will eventually slow down your computer.
To solve that docker-desktop UI for Mac and Windows provides an easier alternative compared to minikube, which you could simply activate the Kubernetes feature on your docker-desktop UI:
once it is setup you can right click on the docker desktop icon > Kubernetes
To verify now that your deployement/service works properly:
kubectl apply -f /file.yaml

Answer 4

For this specific (and really great) course about Kubernetes on Udemy from Richard Chesterwood the following solution should work out of the box on Windows: just start the minikube with hyper-v driver, then it will automatically map all the ports you are expecting onto your host machine, like detailed explained here by Dawid Kruk. Therefore all you need to start minikube "correctly" is the following command:
minikube start --driver=hyperv
Be careful by specifying exact amount of memory you give to this minikube instance. In my experiences hyper-v is a bit sensitive about how much memory you will give to it, what could result in errors:
minikube start --driver=hyperv --memory=8192
...
Not enough memory in the system to start the virtual machine minikube.
Could not initialize memory: Not enough memory resources are available to complete this operation. (0x8007000E).
'minikube' failed to start. (Virtual machine ID D4BC7B61-4E4D-4079-94DE-...)
Not enough memory in the system to start the virtual machine minikube with ram size 8192 megabytes. (Virtual machine ID ...)
Therefore just use the unspecific command given above and hyper-v will figure out, how much memory it really needs on it's own.

Answer 5

If you are running minikube in a Windows, then minikube must run as an Administrator command prompt window.