How to resolve paths conflict in nginx ingress? - kubernetes-ingress

Question

I'm running sentry on my EKS cluster and according to the official documentation it can only be exposed on rootPath "/" i'm also exposing keycloak on "/auth" which is the default web-context
So i deployed nginx ingress controller and ingress resources to match these paths, but the problem i encountered was that sentry path ("/") is always redirected to "/auth" which is the default path of keycloak which would cause a conflict. in my case i'm not allowed to change the web-context of keycloak so i tried to deploy another nginx ingress controller for sentry with the same class but i did not know how to do it since all examples are using ingress controllers with different classes. so i would like to know if this possible how to deploy a seconf nginx ingress which is pretty much the same as the first one or if there is another solution please help me know it.
Here is nginx ingress controller i use :
apiVersion: v1
kind: Namespace
metadata:
name: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
---
# Source: ingress-nginx/templates/controller-serviceaccount.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
name: ingress-nginx
namespace: ingress-nginx
---
# Source: ingress-nginx/templates/controller-configmap.yaml
apiVersion: v1
kind: ConfigMap
metadata:
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
name: ingress-nginx-controller
namespace: ingress-nginx
data:
---
# Source: ingress-nginx/templates/clusterrole.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
name: ingress-nginx
namespace: ingress-nginx
rules:
- apiGroups:
- ''
resources:
- configmaps
- endpoints
- nodes
- pods
- secrets
verbs:
- list
- watch
- apiGroups:
- ''
resources:
- nodes
verbs:
- get
- apiGroups:
- ''
resources:
- services
verbs:
- get
- list
- update
- watch
- apiGroups:
- extensions
- networking.k8s.io # k8s 1.14+
resources:
- ingresses
verbs:
- get
- list
- watch
- apiGroups:
- ''
resources:
- events
verbs:
- create
- patch
- apiGroups:
- extensions
- networking.k8s.io # k8s 1.14+
resources:
- ingresses/status
verbs:
- update
- apiGroups:
- networking.k8s.io # k8s 1.14+
resources:
- ingressclasses
verbs:
- get
- list
- watch
---
# Source: ingress-nginx/templates/clusterrolebinding.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
name: ingress-nginx
namespace: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: ingress-nginx
subjects:
- kind: ServiceAccount
name: ingress-nginx
namespace: ingress-nginx
---
# Source: ingress-nginx/templates/controller-role.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
name: ingress-nginx
namespace: ingress-nginx
rules:
- apiGroups:
- ''
resources:
- namespaces
verbs:
- get
- apiGroups:
- ''
resources:
- configmaps
- pods
- secrets
- endpoints
verbs:
- get
- list
- watch
- apiGroups:
- ''
resources:
- services
verbs:
- get
- list
- update
- watch
- apiGroups:
- extensions
- networking.k8s.io # k8s 1.14+
resources:
- ingresses
verbs:
- get
- list
- watch
- apiGroups:
- extensions
- networking.k8s.io # k8s 1.14+
resources:
- ingresses/status
verbs:
- update
- apiGroups:
- networking.k8s.io # k8s 1.14+
resources:
- ingressclasses
verbs:
- get
- list
- watch
- apiGroups:
- ''
resources:
- configmaps
resourceNames:
- ingress-controller-leader-nginx
verbs:
- get
- update
- apiGroups:
- ''
resources:
- configmaps
verbs:
- create
- apiGroups:
- ''
resources:
- endpoints
verbs:
- create
- get
- update
- apiGroups:
- ''
resources:
- events
verbs:
- create
- patch
---
# Source: ingress-nginx/templates/controller-rolebinding.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
name: ingress-nginx
namespace: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: ingress-nginx
subjects:
- kind: ServiceAccount
name: ingress-nginx
namespace: ingress-nginx
---
# Source: ingress-nginx/templates/controller-service-webhook.yaml
apiVersion: v1
kind: Service
metadata:
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
name: ingress-nginx-controller-admission
namespace: ingress-nginx
spec:
type: ClusterIP
ports:
- name: https-webhook
port: 443
targetPort: webhook
selector:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/component: controller
---
# Source: ingress-nginx/templates/controller-service.yaml
apiVersion: v1
kind: Service
metadata:
annotations:
service.beta.kubernetes.io/aws-load-balancer-backend-protocol: tcp
service.beta.kubernetes.io/aws-load-balancer-connection-idle-timeout: '60'
service.beta.kubernetes.io/aws-load-balancer-cross-zone-load-balancing-enabled: 'true'
service.beta.kubernetes.io/aws-load-balancer-type: nlb
service.beta.kubernetes.io/aws-load-balancer-internal: "true"
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
name: ingress-nginx-controller
namespace: ingress-nginx
spec:
type: LoadBalancer
externalTrafficPolicy: Local
ports:
- name: http
port: 80
protocol: TCP
targetPort: http
- name: https
port: 443
protocol: TCP
targetPort: https
selector:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/component: controller
---
# Source: ingress-nginx/templates/controller-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
name: ingress-nginx-controller
namespace: ingress-nginx
spec:
selector:
matchLabels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/component: controller
revisionHistoryLimit: 10
minReadySeconds: 0
template:
metadata:
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/component: controller
spec:
dnsPolicy: ClusterFirst
containers:
- name: controller
image: quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.31.1
imagePullPolicy: IfNotPresent
lifecycle:
preStop:
exec:
command:
- /wait-shutdown
args:
- /nginx-ingress-controller
- --publish-service=ingress-nginx/ingress-nginx-controller
- --election-id=ingress-controller-leader
- --ingress-class=nginx
- --configmap=ingress-nginx/ingress-nginx-controller
- --validating-webhook=:8443
- --validating-webhook-certificate=/usr/local/certificates/cert
- --validating-webhook-key=/usr/local/certificates/key
securityContext:
capabilities:
drop:
- ALL
add:
- NET_BIND_SERVICE
runAsUser: 101
allowPrivilegeEscalation: true
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
livenessProbe:
httpGet:
path: /healthz
port: 10254
scheme: HTTP
initialDelaySeconds: 10
periodSeconds: 10
timeoutSeconds: 1
successThreshold: 1
failureThreshold: 3
readinessProbe:
httpGet:
path: /healthz
port: 10254
scheme: HTTP
initialDelaySeconds: 10
periodSeconds: 10
timeoutSeconds: 1
successThreshold: 1
failureThreshold: 3
ports:
- name: http
containerPort: 80
protocol: TCP
- name: https
containerPort: 443
protocol: TCP
- name: webhook
containerPort: 8443
protocol: TCP
volumeMounts:
- name: webhook-cert
mountPath: /usr/local/certificates/
readOnly: true
resources:
requests:
cpu: 100m
memory: 90Mi
serviceAccountName: ingress-nginx
terminationGracePeriodSeconds: 300
volumes:
- name: webhook-cert
secret:
secretName: ingress-nginx-admission
---
# Source: ingress-nginx/templates/admission-webhooks/validating-webhook.yaml
apiVersion: admissionregistration.k8s.io/v1beta1
kind: ValidatingWebhookConfiguration
metadata:
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: admission-webhook
name: ingress-nginx-admission
namespace: ingress-nginx
webhooks:
- name: validate.nginx.ingress.kubernetes.io
rules:
- apiGroups:
- extensions
- networking.k8s.io
apiVersions:
- v1beta1
operations:
- CREATE
- UPDATE
resources:
- ingresses
failurePolicy: Fail
clientConfig:
service:
namespace: ingress-nginx
name: ingress-nginx-controller-admission
path: /extensions/v1beta1/ingresses
---
# Source: ingress-nginx/templates/admission-webhooks/job-patch/clusterrole.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: ingress-nginx-admission
annotations:
helm.sh/hook: pre-install,pre-upgrade,post-install,post-upgrade
helm.sh/hook-delete-policy: before-hook-creation,hook-succeeded
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: admission-webhook
namespace: ingress-nginx
rules:
- apiGroups:
- admissionregistration.k8s.io
resources:
- validatingwebhookconfigurations
verbs:
- get
- update
---
# Source: ingress-nginx/templates/admission-webhooks/job-patch/clusterrolebinding.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: ingress-nginx-admission
annotations:
helm.sh/hook: pre-install,pre-upgrade,post-install,post-upgrade
helm.sh/hook-delete-policy: before-hook-creation,hook-succeeded
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: admission-webhook
namespace: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: ingress-nginx-admission
subjects:
- kind: ServiceAccount
name: ingress-nginx-admission
namespace: ingress-nginx
---
# Source: ingress-nginx/templates/admission-webhooks/job-patch/job-createSecret.yaml
apiVersion: batch/v1
kind: Job
metadata:
name: ingress-nginx-admission-create
annotations:
helm.sh/hook: pre-install,pre-upgrade
helm.sh/hook-delete-policy: before-hook-creation,hook-succeeded
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: admission-webhook
namespace: ingress-nginx
spec:
template:
metadata:
name: ingress-nginx-admission-create
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: admission-webhook
spec:
containers:
- name: create
image: jettech/kube-webhook-certgen:v1.0.0
imagePullPolicy: IfNotPresent
args:
- create
- --host=ingress-nginx-controller-admission,ingress-nginx-controller-admission.ingress-nginx.svc
- --namespace=ingress-nginx
- --secret-name=ingress-nginx-admission
restartPolicy: OnFailure
serviceAccountName: ingress-nginx-admission
securityContext:
runAsNonRoot: true
runAsUser: 2000
---
# Source: ingress-nginx/templates/admission-webhooks/job-patch/job-patchWebhook.yaml
apiVersion: batch/v1
kind: Job
metadata:
name: ingress-nginx-admission-patch
annotations:
helm.sh/hook: post-install,post-upgrade
helm.sh/hook-delete-policy: before-hook-creation,hook-succeeded
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: admission-webhook
namespace: ingress-nginx
spec:
template:
metadata:
name: ingress-nginx-admission-patch
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: admission-webhook
spec:
containers:
- name: patch
image: jettech/kube-webhook-certgen:v1.0.0
imagePullPolicy:
args:
- patch
- --webhook-name=ingress-nginx-admission
- --namespace=ingress-nginx
- --patch-mutating=false
- --secret-name=ingress-nginx-admission
- --patch-failure-policy=Fail
restartPolicy: OnFailure
serviceAccountName: ingress-nginx-admission
securityContext:
runAsNonRoot: true
runAsUser: 2000
---
# Source: ingress-nginx/templates/admission-webhooks/job-patch/role.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
name: ingress-nginx-admission
annotations:
helm.sh/hook: pre-install,pre-upgrade,post-install,post-upgrade
helm.sh/hook-delete-policy: before-hook-creation,hook-succeeded
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: admission-webhook
namespace: ingress-nginx
rules:
- apiGroups:
- ''
resources:
- secrets
verbs:
- get
- create
---
# Source: ingress-nginx/templates/admission-webhooks/job-patch/rolebinding.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: ingress-nginx-admission
annotations:
helm.sh/hook: pre-install,pre-upgrade,post-install,post-upgrade
helm.sh/hook-delete-policy: before-hook-creation,hook-succeeded
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: admission-webhook
namespace: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: ingress-nginx-admission
subjects:
- kind: ServiceAccount
name: ingress-nginx-admission
namespace: ingress-nginx
---
# Source: ingress-nginx/templates/admission-webhooks/job-patch/serviceaccount.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
name: ingress-nginx-admission
annotations:
helm.sh/hook: pre-install,pre-upgrade,post-install,post-upgrade
helm.sh/hook-delete-policy: before-hook-creation,hook-succeeded
labels:
helm.sh/chart: ingress-nginx-2.0.1
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/version: 0.31.1
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: admission-webhook
namespace: ingress-nginx
Here is the ingress resources :
Keycloak :
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
name: "keycloak-ingress"
annotations:
kubernetes.io/ingress.class: nginx
labels:
app: keycloak-ingress
spec:
rules:
- http:
paths:
- path: /auth
backend:
serviceName: keycloak
servicePort: 8080
Sentry :
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
name: "sentry-ingress"
namespace: "tools"
annotations:
kubernetes.io/ingress.class: sentry-nginx
nginx.ingress.kubernetes.io/force-ssl-redirect: "true"
labels:
app: sentry-ingress
spec:
rules:
- http:
paths:
- path: /
backend:
serviceName: "sentry"
servicePort: 9000

Answer 1

keycloak is exposed on "/auth" which is the default web-context.
I understand that as default web-context, means that you want everything sent to / should be redirected to keycloak.
So you need to set a different target for Sentry, like /sentry.
kubernetes.io/ingress.class: sentry-nginx is not a valid ingress.class in kubernetes.io that's probably why your ingress is not being considered.
Only one deployment of Nginx-Ingress is needed to proxy traffic between multiple apps.
The trick here is to expose sentry as mydomain.com/sentry and the app itself receives the connection directly on / as required.
In order to achieve it you can use rewrite-target, learn more here.
It will create a capture group and send to the appropriate service.
This is what your ingress should look like:
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
name: "my-ingress"
annotations:
kubernetes.io/ingress.class: nginx
nginx.ingress.kubernetes.io/rewrite-target: /$2
labels:
app: my-ingress
spec:
rules:
- http:
paths:
- path: /(.*)
backend:
serviceName: keycloak
servicePort: 8080
- path: /sentry(/|$)(.*)
backend:
serviceName: sentry
servicePort: 9000
This will do the following:
Requests to / will be delivered to keycloak as /
Requests to /auth will be delivered to keycloak as /
Requests to /auth/foo will be delivered to keycloak as /foo
Requests to /sentry will be delivered to sentry as /
Requests to /sentry/bar will be delivered to sentry as /bar
Nginx Ingress uses Path Priority:
In NGINX, regular expressions follow a first match policy. In order to enable more accurate path matching, ingress-nginx first orders the paths by descending length before writing them to the NGINX template as location blocks.
Example:
this is the ingress in my example echo-ingress.yaml:
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
name: echo-ingress
annotations:
kubernetes.io/ingress.class: nginx
nginx.ingress.kubernetes.io/rewrite-target: /$2
spec:
rules:
- host: mydomain.com
http:
paths:
- path: /(.*)
backend:
serviceName: echo1-svc
servicePort: 80
- path: /sentry(/|$)(.*)
backend:
serviceName: echo2-svc
servicePort: 80
I created 2 echo apps, to demonstrate it:
echo1-deploy.yaml: emulates your keycloak
apiVersion: apps/v1
kind: Deployment
metadata:
name: echo1-deploy
spec:
selector:
matchLabels:
app: echo1-app
template:
metadata:
labels:
app: echo1-app
spec:
containers:
- name: echo1-app
image: mendhak/http-https-echo
ports:
- name: http
containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
name: echo1-svc
spec:
selector:
app: echo1-app
ports:
- protocol: TCP
port: 80
targetPort: 80
echo2-deploy.yaml: emulates your sentry
apiVersion: apps/v1
kind: Deployment
metadata:
name: echo2-deploy
spec:
selector:
matchLabels:
app: echo2-app
template:
metadata:
labels:
app: echo2-app
spec:
containers:
- name: echo2-app
image: mendhak/http-https-echo
ports:
- name: http
containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
name: echo2-svc
spec:
selector:
app: echo2-app
ports:
- protocol: TCP
port: 80
targetPort: 80
Let's apply and test the outcome:
$ kubectl apply -f echo1-deploy.yaml
deployment.apps/echo1-deploy created
service/echo1-svc created
$ kubectl apply -f echo2-deploy.yaml
deployment.apps/echo2-deploy created
service/echo2-svc created
$ kubectl apply -f echo-ingress.yaml
ingress.networking.k8s.io/echo-ingress created
$ kubectl get ingress
NAME HOSTS ADDRESS PORTS AGE
echo-ingress mydomain.com 35.188.7.149 80 48s
$ tail -n 1 /etc/hosts
35.188.7.149 mydomain.com
$ curl mydomain.com/sentry
{"path": "/",
...suppressed output...
"os": {"hostname": "echo2-deploy-7bcb8f8d5f-dwzkr"}
}
$ curl mydomain.com/auth
{"path": "/",
...suppressed output...
"os": {"hostname": "echo1-deploy-764d5df7cf-6m5nz"}
}
$ curl mydomain.com
{"path": "/",
"os": {"hostname": "echo1-deploy-764d5df7cf-6m5nz"}
}
We can see that the requested were correctly forwarded to the pod responsible for the app set in the ingress with the rewrite target.
Considerations:
Sentry "can only be exposed on rootPath "/"
I found out that Sentry can be exposed on other paths, check here and here, it might be worth checking.
If I got wrong your environment or you have any question let me know in the comments and I'll modify it =)