Know your real clients: Use PROXY protocol on Red Hat OpenShift on IBM Cloud

As of 14 June 2023, PROXY protocol is supported for Ingress Controllers in Red Hat OpenShift on IBM Cloud clusters hosted on VPC infrastructure.

Introduction

Fashionable software program architectures usually embrace a number of layers of proxies and cargo balancers. Preserving the IP deal with of the unique shopper by way of these layers is difficult, however may be required to your use circumstances. A possible answer for the issue is to make use of PROXY Protocol.

Beginning with Red Hat OpenShift on IBM Cloud model 4.13, PROXY protocol is now supported for Ingress Controllers in clusters hosted on VPC infrastructure.

In case you are excited about utilizing PROXY protocol for Ingress Controllers on IBM Cloud Kubernetes Service clusters, you will discover extra data in our previous blog post.

Establishing PROXY protocol for OpenShift Ingress Controllers

When utilizing PROXY protocol for supply deal with preservation, all proxies that terminate TCP connections within the chain have to be configured to ship and obtain PROXY protocol headers after initiating L4 connections. Within the case of Crimson Hat OpenShift on IBM Cloud clusters working on VPC infrastructure, we’ve two proxies: the VPC Software Load Balancer (ALB) and the Ingress Controller.

On OpenShift clusters, the Ingress Operator is answerable for managing the Ingress Controller cases and the load balancers used to show the Ingress Controllers. The operator watches IngressController sources on the cluster and makes changes to match the specified state.

Due to the Ingress Operator, we are able to allow PROXY protocol for each of our proxies directly. All we have to do is to vary the endpointPublishingStrategy configuration on our IngressController useful resource:

endpointPublishingStrategy:
  sort: LoadBalancerService
  loadBalancer:
    scope: Exterior
    providerParameters:
      sort: IBM
      ibm:
        protocol: PROXY

Whenever you apply the earlier configuration, the operat,or switches the Ingress Controller into PROXY protocol mode and provides the service.kubernetes.io/ibm-load-balancer-cloud-provider-enable-features: "proxy-protocol" annotation to the corresponding LoadBalancer typed Service useful resource, enabling PROXY protocol for the VPC ALB.

Instance

On this instance, we deployed a take a look at software in a single-zone Crimson Hat OpenShift on IBM Cloud 4.13 cluster that makes use of VPC technology 2 compute. The applying accepts HTTP connections and returns details about the obtained requests, such because the shopper deal with. The applying is uncovered by the default-router created by the OpenShift Ingress Operator on the echo.instance.com area.

Consumer data with out utilizing PROXY protocol

By default, the PROXY protocol will not be enabled. Let’s take a look at accessing the applying:

$ curl https://echo.instance.com

Hostname: test-application-cd7cd98f7-9xbvm

Pod Info:
    -no pod data available-

Server values:
    server_version=nginx: 1.13.3 - lua: 10008

Request Info:
    client_address=172.24.84.165
    technique=GET
    actual path=/
    question=
    request_version=1.1
    request_scheme=http
    request_uri=http://echo.instance.com:8080/

Request Headers:
    settle for=*/*
    forwarded=for=10.240.128.45;host=echo.instance.com;proto=https
    host=echo.instance.com
    user-agent=curl/7.87.0
    x-forwarded-for=10.240.128.45
    x-forwarded-host=echo.instance.com
    x-forwarded-port=443
    x-forwarded-proto=https

Request Physique:
    -no physique in request-

As you possibly can see, the deal with within the x-forwarded-for header 10.240.128.45 doesn’t match your deal with. That’s the employee node’s deal with that obtained the request from the VPC load balancer. Which means we can’t get better the unique deal with of the shopper:

$ kubectl get nodes
NAME            STATUS   ROLES           AGE     VERSION
10.240.128.45   Prepared    grasp,employee   5h33m   v1.26.3+b404935
10.240.128.46   Prepared    grasp,employee   5h32m   v1.26.3+b404935

Enabling PROXY protocol on the default ingress controller

First, edit the Ingress Controller useful resource:

oc -n openshift-ingress-operator edit ingresscontroller/default

Within the Ingress controller useful resource, discover the spec.endpointPublishingStrategy.loadBalancer part and outline the next providerParameters values:

endpointPublishingStrategy:
  loadBalancer:
    providerParameters:
      sort: IBM
      ibm:
        protocol: PROXY
    scope: Exterior
  sort: LoadBalancerService

Then, save and apply the useful resource.

Consumer data utilizing PROXY protocol

Wait till the default-router pods are recycled and take a look at entry to the applying once more:

$ curl https://echo.instance.com


Hostname: test-application-cd7cd98f7-9xbvm

Pod Info:
    -no pod data available-

Server values:
    server_version=nginx: 1.13.3 - lua: 10008

Request Info:
    client_address=172.24.84.184
    technique=GET
    actual path=/
    question=
    request_version=1.1
    request_scheme=http
    request_uri=http://echo.instance.com:8080/

Request Headers:
    settle for=*/*
    forwarded=for=192.0.2.42;host=echo.instance.com;proto=https
    host=echo.instance.com
    user-agent=curl/7.87.0
    x-forwarded-for=192.0.2.42
    x-forwarded-host=echo.instance.com
    x-forwarded-port=443
    x-forwarded-proto=https

Request Physique:
    -no physique in request-

This time, you will discover the precise shopper deal with 192.0.2.42 within the request headers, which is the precise public IP deal with of the unique shopper.

Limitations

The PROXY protocol characteristic on Crimson Hat OpenShift on IBM Cloud is supported for less than VPC technology 2 clusters that run 4.13 OpenShift model or later.

Extra data

For extra data, try our official documentation about exposing apps with load balancers, enabling PROXY protocol for Ingress Controllers or the Red Hat OpenShift documentation.