cleans up the ingress-dns docs
rahil-p
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---
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title: "Ingress DNS"
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linkTitle: "Minikube Ingress DNS"
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linkTitle: "Ingress DNS"
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weight: 1
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date: 2021-06-03
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date: 2021-11-08
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---
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DNS service for ingress controllers running on your minikube server
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## Overview
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### Problem
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When running minikube locally you are highly likely to want to run your services on an ingress controller so that you
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don't have to use minikube tunnel or NodePorts to access your services. While NodePort might be ok in a lot of
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circumstances in order to test some features an ingress is necessary. Ingress controllers are great because you can
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define your entire architecture in something like a helm chart and all your services will be available. There is only
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1 problem. That is that your ingress controller works basically off of dns and while running minikube that means that
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your local dns names like `myservice.test` will have to resolve to `$(minikube ip)` not really a big deal except the
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only real way to do this is to add an entry for every service in your `/etc/hosts` file. This gets messy for obvious
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reasons. If you have a lot of services running that each have their own dns entry then you have to set those up
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manually. Even if you automate it you then need to rely on the host operating system storing configurations instead of
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storing them in your cluster. To make it worse it has to be constantly maintained and updated as services are added,
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remove, and renamed. I call it the `/etc/hosts` pollution problem.
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When running minikube locally, you may want to run your services on an ingress controller so that you don't have to use
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minikube tunnel or NodePorts to access your services. While NodePort might be okay in a lot of circumstances, an ingress
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is necessary to test some features. Ingress controllers are great because you can define your entire architecture in
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something like a helm chart and all your services will be available.
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However, for minikube, there is an additional challenge. Your ingress controller relies on DNS, so local DNS names like
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`myservice.test` will have to resolve to your `minikube ip`. The only real way to do this is to add an entry for every
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service in your `/etc/hosts` file. This gets messy for obvious reasons. For each service you are running that each has
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its own DNS entry, you will need to configure it manually. Even if you automate it, you then need to rely on the host
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operating system for storing configurations instead of storing them in your cluster. To make it worse, these
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configurations have to be constantly maintained and updated as services are added, remove, and renamed. I call it the
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`/etc/hosts` pollution problem.
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### Solution
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What if you could just access your local services magically without having to edit your `/etc/hosts` file? Well now you
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can. This addon acts as a DNS service that runs inside your kubernetes cluster. All you have to do is install the
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service and add the `$(minikube ip)` as a DNS server on your host machine. Each time the dns service is queried an
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API call is made to the kubernetes master service for a list of all the ingresses. If a match is found for the name a
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response is given with an IP address as the `$(minikube ip)`. So for example lets say my minikube ip address is
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`192.168.99.106` and I have an ingress controller with the name of `myservice.test` then I would get a result like so:
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What if you could just access your local services magically without having to edit your `/etc/hosts` file? Well, now you
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can. The `ingress-dns` addon acts as a DNS service that runs inside your Kubernetes cluster. All you have to do is
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install the service and add the `$(minikube ip)` as a DNS server on your host machine. Each time the DNS service is
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queried, an API call is made to the Kubernetes master service for a list of all the ingresses. If a match is found for
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the name, a response is given with an IP address matching `minikube ip`. For example, with a `minikube ip` of
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`192.168.99.106` and an ingress rule for `myservice.test` configured in the cluster, a DNS query from the host would
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produce:
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```text
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#bash:~$ nslookup myservice.test $(minikube ip)
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@ -41,56 +43,57 @@ Address: 192.168.99.169
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## Installation
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### Start minikube
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```
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<h3 class="step"><span class="fa-stack fa-1x"><i class="fa fa-circle fa-stack-2x"></i><strong class="fa-stack-1x text-primary">1</strong></span>Start minikube</h2>
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```bash
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minikube start
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```
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### Install the kubernetes resources
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<h3 class="step"><span class="fa-stack fa-1x"><i class="fa fa-circle fa-stack-2x"></i><strong class="fa-stack-1x text-primary">2</strong></span>Enable the addons</h2>
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```bash
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minikube addons enable ingress
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minikube addons enable ingress-dns
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```
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### Add the minikube ip as a dns server
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<h3 class="step"><span class="fa-stack fa-1x"><i class="fa fa-circle fa-stack-2x"></i><strong class="fa-stack-1x text-primary">3</strong></span>Add the `minikube ip` as a DNS server</h2>
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#### Mac OS
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Create a file in `/etc/resolver/minikube-profilename-test`
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```
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domain test
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nameserver 192.168.99.169
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search_order 1
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timeout 5
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```
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Replace `192.168.99.169` with your minikube ip and `profilename` is the name of the minikube profile for the
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corresponding ip address
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{{% card %}}
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If you have multiple minikube ips you must configure multiple files
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{{% quiz_row base="" name="Operating system" %}}
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{{% quiz_button option="Linux" %}} {{% quiz_button option="macOS" %}} {{% quiz_button option="Windows" %}}
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{{% /quiz_row %}}
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See https://www.unix.com/man-page/opendarwin/5/resolver/
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Note that even though the `port` feature is documented. It does not actually work.
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{{% card %}}
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{{% quiz_instruction_plain id="/Linux" %}}
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Update the file `/etc/resolvconf/resolv.conf.d/base` to have the following contents.
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#### Linux
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Update the file `/etc/resolvconf/resolv.conf.d/base` to have the following contents
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```
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search test
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nameserver 192.168.99.169
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timeout 5
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```
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Replace `192.168.99.169` with your minikube ip
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If your linux OS uses `systemctl` run the following commands
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Replace `192.168.99.169` with your `minikube ip`.
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If your Linux OS uses `systemctl`, run the following commands.
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```bash
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sudo resolvconf -u
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systemctl disable --now resolvconf.service
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```
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If your linux does not use `systemctl` run the following commands
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If your Linux OS does not use `systemctl`, run the following commands.
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TODO add supporting docs for Linux OS that do not use `systemctl`
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```bash
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# TODO add supporting docs for Linux OS that do not use `systemctl`
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```
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See https://linux.die.net/man/5/resolver
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When you are using Network Manager with the dnsmasq plugin, you can add an additional configuration file, but you need
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When you are using Network Manager with the `dnsmasq` plugin, you can add an additional configuration file, but you need
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to restart NetworkManager to activate the change.
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```bash
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@ -100,62 +103,95 @@ systemctl restart NetworkManager.service
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Also see `dns=` in [NetworkManager.conf](https://developer.gnome.org/NetworkManager/stable/NetworkManager.conf.html).
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#### Windows
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Open `Powershell` as Administrator and execute the following
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{{% /quiz_instruction_plain %}}
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{{% quiz_instruction_plain id="/macOS" %}}
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Create a file in `/etc/resolver/minikube-test` with the following content.
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```
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domain test
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nameserver 192.168.99.169
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search_order 1
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timeout 5
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```
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Replace `192.168.99.169` with your `minikube ip`.
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If you have multiple minikube IPs, you must configure a file for each.
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See https://www.unix.com/man-page/opendarwin/5/resolver/
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Note that the `port` feature does not work as documented.
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{{% /quiz_instruction_plain %}}
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{{% quiz_instruction_plain id="/Windows" %}}
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Open `Powershell` as Administrator and execute the following.
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```sh
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Add-DnsClientNrptRule -Namespace ".test" -NameServers "$(minikube ip)"
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```
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The following will remove any matching rules, before creating one. This is helpful if your minikube has a new ip
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The following will remove any matching rules before creating a new one. This is useful for updating the `minikube ip`.
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```sh
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Get-DnsClientNrptRule | Where-Object {$_.Namespace -eq '.test'} | Remove-DnsClientNrptRule -Force; Add-DnsClientNrptRule -Namespace ".test" -NameServers "$(minikube ip)"
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```
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{{% /quiz_instruction_plain %}}
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{{% /card %}}
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{{% /card %}}
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## Testing
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### Add the test ingress
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<h3 class="step"><span class="fa-stack fa-1x"><i class="fa fa-circle fa-stack-2x"></i><strong class="fa-stack-1x text-primary">1</strong></span>Add the test ingress</h2>
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```bash
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kubectl apply -f https://raw.githubusercontent.com/kubernetes/minikube/master/deploy/addons/ingress-dns/example/example.yaml
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```
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Note: Minimum Kubernetes version for example ingress is 1.19
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Note: Minimum Kubernetes version for the example ingress is 1.19
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<h3 class="step"><span class="fa-stack fa-1x"><i class="fa fa-circle fa-stack-2x"></i><strong class="fa-stack-1x text-primary">2</strong></span>Confirm that DNS queries are returning A records</h2>
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### Validate DNS queries are returning A records
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```bash
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nslookup hello-john.test $(minikube ip)
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nslookup hello-jane.test $(minikube ip)
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```
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### Validate domain names are resolving on host OS
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<h3 class="step"><span class="fa-stack fa-1x"><i class="fa fa-circle fa-stack-2x"></i><strong class="fa-stack-1x text-primary">3</strong></span>Confirm that domain names are resolving on the host OS</h2>
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```bash
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ping hello-john.test
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ping hello-jane.test
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```
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Expected results:
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```text
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PING hello-john.test (192.168.99.169): 56 data bytes
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64 bytes from 192.168.99.169: icmp_seq=0 ttl=64 time=0.361 ms
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```
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```bash
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ping hello-jane.test
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```
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```text
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PING hello-jane.test (192.168.99.169): 56 data bytes
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64 bytes from 192.168.99.169: icmp_seq=0 ttl=64 time=0.262 ms
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```
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### Curl the example server
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<h3 class="step"><span class="fa-stack fa-1x"><i class="fa fa-circle fa-stack-2x"></i><strong class="fa-stack-1x text-primary">4</strong></span>Curl the example server</h2>
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```bash
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curl http://hello-john.test
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curl http://hello-jane.test
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```
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Expected result:
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Expected results:
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```text
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Hello, world!
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Version: 1.0.0
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Hostname: hello-world-app-557ff7dbd8-64mtv
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```
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```bash
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curl http://hello-jane.test
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```
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Expected result:
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```text
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Hello, world!
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Version: 1.0.0
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@ -0,0 +1,3 @@
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<div data-quiz-id="{{ with .Get "id"}}{{.}}{{end}}" class="quiz-instruction">
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{{ .Inner }}
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</div>
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