My goal is to make my web application (deployed on Kubernetes 1.4 cluster) see the IP of the client that originally made the HTTP request. As I'm planning to run the application on a bare-metal cluster, GCE and the service.alpha.kubernetes.io/external-traffic: OnlyLocal service annotation introduced in 1.4 is not applicable for me.
Looking for alternatives, I've found this question which is proposing to set up an Ingress to achieve my goal. So, I've set up the Ingress and the NginX Ingress Controller. The deployment went smoothly and I was able to connect to my web app via the Ingress Address and port 80. However in the logs I still see cluster-internal IP (from 172.16.0.0/16) range - and that means that the external client IPs are not being properly passed via the Ingress. Could you please tell me what do I need to configure in addition to the above to make it work?
My Ingress' config:
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: myWebApp
spec:
backend:
serviceName: myWebApp
servicePort: 8080
As a layer 4 proxy, Nginx cannot retain the original source IP address in the actual IP packets. You can work around this using the Proxy protocol (the link points to the HAProxy documentation, but Nginx also supports it).
For this to work however, the upstream server (meaning the myWebApp service in your case) also needs to support this protocol. In case your upstream application also uses Nginx, you can enable proxy protocol support in your server configuration as documented in the official documentation.
According to the Nginx Ingress Controller's documentation, this feature can be enabled in the Ingress Controller using a Kubernetes ConfigMap:
apiVersion: v1
kind: ConfigMap
metadata:
name: nginx-ingress-controller
data:
use-proxy-protocol: "true"
Specify the name of the ConfigMap in your Ingress controller manifest, by adding the --nginx-configmap=<insert-configmap-name> flag to the command-line arguments.
Related
I have a working Nexus 3 pod, reachable on port 30080 (with NodePort): http://nexus.mydomain:30080/ works perfectly from all hosts (from the cluster or outside).
Now I'm trying to make it accessible at the port 80 (for obvious reasons).
Following the docs, I've implemented it like that (trivial):
[...]
---
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
name: nexus-ingress
namespace: nexus-ns
annotations:
nginx.ingress.kubernetes.io/rewrite-target: /$1
spec:
rules:
- host: nexus.mydomain
http:
paths:
- path: /
pathType: Prefix
backend:
serviceName: nexus-service
servicePort: 80
Applying it works without errors. But when I try to reach http://nexus.mydomain, I get:
Service Unavailable
No logs are shown (the webapp is not hit).
What did I miss ?
K3s Lightweight Kubernetes
K3s is designed to be a single binary of less than 40MB that completely implements the Kubernetes API. In order to achieve this, they removed a lot of extra drivers that didn't need to be part of the core and are easily replaced with add-ons.
As I mentioned in comments, K3s as default is using Traefik Ingress Controller.
Traefik is an open-source Edge Router that makes publishing your services a fun and easy experience. It receives requests on behalf of your system and finds out which components are responsible for handling them.
This information can be found in K3s Rancher Documentation.
Traefik is deployed by default when starting the server... To prevent k3s from using or overwriting the modified version, deploy k3s with --no-deploy traefik and store the modified copy in the k3s/server/manifests directory. For more information, refer to the official Traefik for Helm Configuration Parameters.
To disable it, start each server with the --disable traefik option.
If you want to deploy Nginx Ingress controller, you can check guide How to use NGINX ingress controller in K3s.
As you are using specific Nginx Ingress like nginx.ingress.kubernetes.io/rewrite-target: /$1, you have to use Nginx Ingress.
If you would use more than 2 Ingress controllers you will need to force using nginx ingress by annotation.
annotations:
kubernetes.io/ingress.class: "nginx"
If mention information won't help, please provide more details like your Deployment, Service.
I do not think you can expose it on port 80 or 443 over a NodePort service or at least it is not recommended.
In this configuration, the NGINX container remains isolated from the
host network. As a result, it can safely bind to any port, including
the standard HTTP ports 80 and 443. However, due to the container
namespace isolation, a client located outside the cluster network
(e.g. on the public internet) is not able to access Ingress hosts
directly on ports 80 and 443. Instead, the external client must append
the NodePort allocated to the ingress-nginx Service to HTTP requests.
-- Bare-metal considerations - NGINX Ingress Controller
* Emphasis added by me.
While it may sound tempting to reconfigure the NodePort range using
the --service-node-port-range API server flag to include unprivileged
ports and be able to expose ports 80 and 443, doing so may result in
unexpected issues including (but not limited to) the use of ports
otherwise reserved to system daemons and the necessity to grant
kube-proxy privileges it may otherwise not require.
This practice is therefore discouraged. See the other approaches
proposed in this page for alternatives.
-- Bare-metal considerations - NGINX Ingress Controller
I did a similar setup a couple of months ago. I installed a MetalLB load balancer and then exposed the service. Depending on your provider (e.g., GKE), a load balancer can even be automatically spun up. So possibly you don't even have to deal with MetalLB, although MetalLB is not hard to setup and works great.
Is there a way to force an SSL upgrade for incoming connections on the ingress load-balancer? Or if that is not possible with, can I disable port :80? I haven't found a good documentation pages that outlines such an option in the YAML file. Thanks a lot in advance!
https://github.com/kubernetes/ingress-gce#frontend-https
You can block HTTP through the annotation kubernetes.io/ingress.allow-http: "false" or redirect HTTP to HTTPS by specifying a custom backend. Unfortunately GCE doesn't handle redirection or rewriting at the L7 layer directly for you, yet. (see https://github.com/kubernetes/ingress-gce#ingress-cannot-redirect-http-to-https)
Update: GCP now handles redirection rules for load balancers, including HTTP to HTTPS. There doesn't appear to be a method to create these through Kubernetes YAML yet.
This was already correctly answered by a comment on the accepted answer. But since the comment is buried I missed it several times.
As of GKE version 1.18.10-gke.600 you can add a k8s frontend config to redirect from http to https.
https://cloud.google.com/kubernetes-engine/docs/how-to/ingress-features#https_redirect
apiVersion: networking.gke.io/v1beta1
kind: FrontendConfig
metadata:
name: ssl-redirect
spec:
redirectToHttps:
enabled: true
# add below to ingress
# metadata:
# annotations:
# networking.gke.io/v1beta1.FrontendConfig: ssl-redirect
The annotation has changed:
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: test
annotations:
kubernetes.io/ingress.allow-http: "false"
spec:
...
Here is the annotation change PR:
https://github.com/kubernetes/contrib/pull/1462/files
If you are not bound to the GCLB Ingress Controller you could have a look at the Nginx Ingress Controller. This controller is different to the builtin one in multiple ways. First and foremost you need to deploy and manage one by yourself. But if you are willing to do so, you get the benefit of not depending on the GCE LB (20$/month) and getting support for IPv6/websockets.
The documentation states:
By default the controller redirects (301) to HTTPS if TLS is enabled for that ingress . If you want to disable that behaviour globally, you
can use ssl-redirect: "false" in the NGINX config map.
The recently released 0.9.0-beta.3 comes with an additional annotation for explicitly enforcing this redirect:
Force redirect to SSL using the annotation ingress.kubernetes.io/force-ssl-redirect
Google has responded to our requests and is testing HTTP->HTTPS SSL redirection on their load balancers. Their latest answer said it should be in Alpha sometime before the end of January 2020.
Their comment:
Thank you for your patience on this issue. The feature is currently in testing and we expect to enter Alpha phase before the end of January. Our PM team will have an announcement with more details as we get closer to the Alpha launch.
My fingers are crossed that we'll have a straightforward solution to this very common feature in the near future.
UPDATE (April 2020):
HTTP(S) rewrites is now a Generally Available feature. It's still a bit rough around the edges and does not work out-of-the-box with the GCE Ingress Controller unfortunately. But time will tell and hopefully a native solution will appear.
A quick update. Here
Now a FrontEndConfig can be make to configure the ingress. Hopes it helps.
Example:
apiVersion: networking.gke.io/v1beta1
kind: FrontendConfig
metadata:
name: my-frontend-config
spec:
redirectToHttps:
enabled: true
responseCodeName: 301
You'll need to make sure that your load balancer supports HTTP and HTTPS
Worked on this for a long time. In case anyone isn't clear on the post above. You would rebuild your ingress with annotation -- kubernetes.io/ingress.allow-http: "false” --
Then delete your ingress and redeploy. The annotation will have the ingress only create a LB for 443, instead of both 443 and 80.
Then you do a compute HTTP LB, not one for GKE.
Gui directions:
Create a load balancer and choose HTTP(S) Load Balancing -- Start configuration.
choose - From Internet to my VMs and continue
Choose a name for the LB
leave the backend configuration blank.
Under Host and path rules, select Advanced host and path rules with the action set to
Redirect the client to different host/path.
Leave the Host redirect field blank.
Select Prefix Redirect and leave the Path value blank.
Chose the redirect response code as 308.
Tick the Enable box for HTTPS redirect.
For the Frontend configuration, leave http and port 80, for ip address select the static
IP address being used for your GKE ingress.
Create this LB.
You will now have all http traffic go to this and 308 redirect to your https ingress for GKE. Super simple config setup and works well.
Note: If you just try to delete the port 80 LB that GKE makes (not doing the annotation change and rebuilding the ingress) and then adding the new redirect compute LB it does work, but you will start to see error messages on your Ingress saying error 400 invalid value for field 'resource.ipAddress " " is in use and would result in a conflict, invalid. It is trying to spin up the port 80 LB and can't because you already have an LB on port 80 using the same IP. It does work but the error is annoying and GKE keeps trying to build it (I think).
Thanks to the comment of #Andrej Palicka and according to the page he provided: https://cloud.google.com/kubernetes-engine/docs/how-to/ingress-features#https_redirect now I have an updated and working solution.
First we need to define a FrontendConfig resource and then we need to tell the Ingress resource to use this FrontendConfig.
Example:
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: myapp-app-ingress
annotations:
kubernetes.io/ingress.global-static-ip-name: myapp-prd
networking.gke.io/managed-certificates: managed-cert
kubernetes.io/ingress.class: "gce"
networking.gke.io/v1beta1.FrontendConfig: myapp-frontend-config
spec:
defaultBackend:
service:
name: myapp-app-service
port:
number: 80
---
apiVersion: networking.gke.io/v1beta1
kind: FrontendConfig
metadata:
name: myapp-frontend-config
spec:
redirectToHttps:
enabled: true
responseCodeName: MOVED_PERMANENTLY_DEFAULT
You can disable HTTP on your cluster (note that you'll need to recreate your cluster for this change to be applied on the load balancer) and then set HTTP-to-HTTPS redirect by creating an additional load balancer on the same IP address.
I spend couple of hours on the same question, and ended up doing what I've just described. It works perfectly.
Redirecting to HTTPS in Kubernetes is somewhat complicated. In my experience, you'll probably want to use an ingress controller such as Ambassador or ingress-nginx to control routing to your services, as opposed to having your load balancer route directly to your services.
Assuming you're using an ingress controller, then:
If you're terminating TLS at the external load balancer and the LB is running in L7 mode (i.e., HTTP/HTTPS), then your ingress controller needs to use X-Forwarded-Proto, and issue a redirect accordingly.
If you're terminating TLS at the external load balancer and the LB is running in TCP/L4 mode, then your ingress controller needs to use the PROXY protocol to do the redirect.
You can also terminate TLS directly in your ingress controller, in which case it has all the necessary information to do the redirect.
Here's a tutorial on how to do this in Ambassador.
I've gotten up Traefik as an Ingress in Kubernetes with this configuration: https://github.com/RedxLus/traefik-simple-kubernetes/tree/master/V1.7
And works well to HTTP and HTTPS but I don't know how can open others ports to forward, for example, a Pod with an Ingress with MySQL in port 3306
Thanks for every answer!
Traefik doesn't support it if you are using an Ingress resource and that resource doesn't support L4 type of traffic like mentioned in the other answer.
But if you are using an Nginx ingress controller there is a workaround, use a ConfigMap with the ingress controller options --tcp-services-configmap and --udp-services-configmap as described here. Then your tcp-services ConfigMap would look something like this:
apiVersion: v1
kind: ConfigMap
metadata:
name: tcp-services
namespace: ingress-nginx
data:
9000: "default/example-go:8080"
The advantage of this is having a single entry point to your cluster (this applies to any ingress that would be used for TCP/UDP) but the downside is overhead of having an extra layer compared to just simply having a Kubernetes Service (NodePort or LoadBalancer) that already listens on TCP/UDP ports.
Kubernetes Ingress API does not support it. But it is possible to use Traefik as TCP proxy for your desired use-case, but only, if you make use of TLS encrypted connections. Otherwise, based on the level 4 protocol, it's not possible to distinguish between the different hostnames and you would have to use one entrypoint per TCP router. Check this issue in GitHub.
The environment: I have a kubernetes cluster set up with namespaces for "dev", "sit" and "prod". In each of these namespaces i have multiple services of type:LoadBalancer which target a specific deployment of a dockerised application (i have multiple applications) so i can access each of these by just using the exposed ip address of the service of whichever namespace i want. Example service looks like this an is very simple:
apiVersion: v1
kind: Service
metadata:
name: application1
spec:
ports:
- port: 80
targetPort: 3000
protocol: TCP
name: http
type: LoadBalancer
selector:
app: application1
The problem: I now want to be able to support multiple versions of all applications (ip:/v1/, ip:/v2/ etc) as to allow the users to migrate to the new version when they are ready and i've been trying to implement path-based routing following this guide. I have managed to restructure my architecture so that i have ReplicationControllers and an ingress which looks at the rules of the path to route to the correct service.
This seems to work if i'd only have one exposed service and a single namespace because i only have DNS host names for production environment and want to use the individual ip address of a service for other environments and i can't figure out how to specify the ingress rules for a service which doesn't have a hostname.
I could just have a loadbalancer for every environment and use path based routing to route to each different services for dev and sit which is not ideal because to access any service we'd have to now use something like this ip/application1 and ip/application2 instead of directly using the service ip address of each application. But my biggest problem is that when i followed the guide and created the ingress, replicationController and a service in my SIT namespace it started affecting the loadbalancer services in my other two environments (as i understand the kubernetes would sometimes try to use the nginx controller from SIT environment on my DEV services and therefore would fail, other times it would use the GCE default configuration and would work).
I tried adding the arg "- --watch-namespace=sit" to limit the scope of the ingress controller to only affect sit but it does not seem to work.
I now want to be able to support multiple versions of all applications (ip:/v1/, ip:/v2/ etc.)
That is exactly what Ingress can do, but the problem is that you want to use IP addresses for routing, but Ingress is using DNS names for that.
I think the best way to implement this is to use an Ingress which will handle requests. On GCE Ingress uses the HTTP(S) load balancer. Yes, you will need a DNS name for that, but it will help you to create a routing which you need.
Also, I highly recommend using TLS encryption for connections.
You can check LetsEncrypt to get a free SSL certificate.
So, the solution should like below:
1. Deploy your Services with type "ClusterIP" instead of "LoadBalancer". You can have more than one Service object for an application so you can do it in parallel with your current configuration.
2. Select any namespace (even special one), for instance - "ingress-ns". We need to create there Service objects which will point to your services in other namespaces. Here is an example of a service (let new DNS name be "my.shiny.new.domain"):
kind: Service
apiVersion: v1
metadata:
name: service-v1
namespace: ingress-ns
spec:
type: ExternalName
externalName: <service>.<namespace>.svc.cluster.local # here is a service name and namespace of your service with version v1.
ports:
- port: 80
3. Now, we have a namespace with several services which are pointing to different versions of your application in different namespaces. Now, we can create an Ingress object which will create an HTTP(S) Load Balancer on GCE with path-based routing:
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: test
namespace: ingress-ns
spec:
rules:
- host: my.shiny.new.domain
http:
paths:
- path: /v1
backend:
serviceName: service-v1
servicePort: 80
- path: /v2
backend:
serviceName: service-v2
servicePort: 80
Kubernetes will create a new HTTP(S) balancer with rules you set up in an Ingress object, and you will have an entry point with cross-namespaces path-based routing, and you don't have to use multiple IP addresses for that.
Actually, you can also manage by that ingress your primary version of an application and use your primary domain with "/" path to handle requests to your production version.
I'm trying to whitelist an IP to access a deployment inside my Kubernetes cluster.
I looked for some documentation online about this, but I only found the
ingress.kubernetes.io/whitelist-source-range
for ingress to grant access to certain IP range. But still, I couldn't manage to isolate the deployment.
Here is the ingress configuration YAML file:
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: ingress-internal
annotations:
kubernetes.io/ingress.class: "istio"
ingress.kubernetes.io/whitelist-source-range: "xxx.xx.xx.0/24, xx.xxx.xx.0/24"
spec:
rules:
- host: white.example.com
http:
paths:
- backend:
serviceName: white
servicePort: 80
I can access the deployment from my whitelisted IP and from the mobile phone (different IP not whitelisted in the config)
Has anyone stepped in the same problem using ingress and Istio?
Any help, hint, docs or alternative configuration will be much appreciated.
Have a look at the annotation overview, it seems that whitelist-source-range is not supported by istio:
whitelist-source-range: Comma-separate list of IP addresses to enable access to.
nginx, haproxy, trafficserver
I managed to solve whitelisting ip address problem for my istio-based service (app that uses istio proxy and exposed through the istio ingress gateway via public LB) using NetworkPolicy.
For my case, here is the topology:
Public Load Balancer (in GKE, using preserve clientIP mode) ==> A dedicated Istio Gateway Controller Pods (see my answer here) ==> My Pods (istio-proxy sidecar container, my main container).
So, I set up 2 network policy:
NetworkPolicy that guards the incoming connection from internet connection to my Istio Ingress Gateway Controller Pods. In my network policy configuration, I just have to set the spec.podSelector.matchLabels field to the pod label of Dedicated Istio Ingress Gateway Controller Pods's
Another NetworkPolicy that limits the incoming connection to my Deployment -> only from the Istio Ingress Gateway Controller pods/deployments.