# Migration: Steps needed between the versions

## v2.0 to v2.1

### Kubernetes CRD

In v2.1, a new Kubernetes CRD called `TraefikService` was added.
While updating an installation to v2.1,
one should apply that CRD, and update the existing `ClusterRole` definition to allow Traefik to use that CRD.

To add that CRD and enhance the permissions, the following definitions need to be applied to the cluster.

```yaml tab="TraefikService"
apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
  name: traefikservices.traefik.containo.us

spec:
  group: traefik.containo.us
  version: v1alpha1
  names:
    kind: TraefikService
    plural: traefikservices
    singular: traefikservice
  scope: Namespaced
```

```yaml tab="ClusterRole"
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
  name: traefik-ingress-controller

rules:
  - apiGroups:
      - ""
    resources:
      - services
      - endpoints
      - secrets
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - extensions
    resources:
      - ingresses
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - extensions
    resources:
      - ingresses/status
    verbs:
      - update
  - apiGroups:
      - traefik.containo.us
    resources:
      - middlewares
      - ingressroutes
      - traefikservices
      - ingressroutetcps
      - tlsoptions
    verbs:
      - get
      - list
      - watch
```

After having both resources applied, Traefik will work properly.

## v2.1 to v2.2

### Headers middleware: accessControlAllowOrigin

`accessControlAllowOrigin` is deprecated.
This field will be removed in future 2.x releases.
Please configure your allowed origins in `accessControlAllowOriginList` instead.

### Kubernetes CRD

In v2.2, new Kubernetes CRDs called `TLSStore` and `IngressRouteUDP` were added.
While updating an installation to v2.2,
one should apply that CRDs, and update the existing `ClusterRole` definition to allow Traefik to use that CRDs.

To add that CRDs and enhance the permissions, the following definitions need to be applied to the cluster.

```yaml tab="TLSStore"
apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
  name: tlsstores.traefik.containo.us

spec:
  group: traefik.containo.us
  version: v1alpha1
  names:
    kind: TLSStore
    plural: tlsstores
    singular: tlsstore
  scope: Namespaced

```

```yaml tab="IngressRouteUDP"
apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
  name: ingressrouteudps.traefik.containo.us

spec:
  group: traefik.containo.us
  version: v1alpha1
  names:
    kind: IngressRouteUDP
    plural: ingressrouteudps
    singular: ingressrouteudp
  scope: Namespaced

```

```yaml tab="ClusterRole"
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
  name: traefik-ingress-controller

rules:
  - apiGroups:
      - ""
    resources:
      - services
      - endpoints
      - secrets
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - extensions
    resources:
      - ingresses
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - extensions
    resources:
      - ingresses/status
    verbs:
      - update
  - apiGroups:
      - traefik.containo.us
    resources:
      - middlewares
      - ingressroutes
      - traefikservices
      - ingressroutetcps
      - ingressrouteudps
      - tlsoptions
      - tlsstores
    verbs:
      - get
      - list
      - watch

```

After having both resources applied, Traefik will work properly.

### Kubernetes Ingress

To enable HTTPS, it is not sufficient anymore to only rely on a TLS section in the Ingress.

#### Expose an Ingress on 80 and 443

Define the default TLS configuration on the HTTPS entry point. 

```yaml tab="Ingress"
kind: Ingress
apiVersion: networking.k8s.io/v1beta1
metadata:
  name: example

spec:
  tls:
  - secretName: my-tls-secret

  rules:
  - host: example.com
    http:
      paths:
      - path: "/foo"
        backend:
          serviceName: example-com
          servicePort: 80
```

Entry points definition and enable Ingress provider:

```yaml tab="File (YAML)"
# Static configuration

entryPoints:
  web:
    address: :80
  websecure:
    address: :443
    http:
      tls: {}

providers:
  kubernetesIngress: {}
```

```toml tab="File (TOML)"
# Static configuration

[entryPoints.web]
  address = ":80"

[entryPoints.websecure]
  address = ":443"
  [entryPoints.websecure.http]
    [entryPoints.websecure.http.tls]

[providers.kubernetesIngress]
```

```bash tab="CLI"
# Static configuration

--entryPoints.web.address=:80
--entryPoints.websecure.address=:443
--entryPoints.websecure.http.tls=true
--providers.kubernetesIngress=true
```

#### Use TLS only on one Ingress

Define the TLS restriction with annotations.

```yaml tab="Ingress"
kind: Ingress
apiVersion: networking.k8s.io/v1beta1
metadata:
  name: example-tls
  annotations:
    traefik.ingress.kubernetes.io/router.entrypoints: websecure
    traefik.ingress.kubernetes.io/router.tls: "true"

spec:
  tls:
  - secretName: my-tls-secret

  rules:
  - host: example.com
    http:
      paths:
      - path: ""
        backend:
          serviceName: example-com
          servicePort: 80
```

Entry points definition and enable Ingress provider:

```yaml tab="File (YAML)"
# Static configuration

entryPoints:
  web:
    address: :80
  websecure:
    address: :443

providers:
  kubernetesIngress: {}
```

```toml tab="File (TOML)"
# Static configuration

[entryPoints.web]
  address = ":80"

[entryPoints.websecure]
  address = ":443"

[providers.kubernetesIngress]
```

```bash tab="CLI"
# Static configuration

--entryPoints.web.address=:80
--entryPoints.websecure.address=:443
--providers.kubernetesIngress=true
```

## v2.2.2 to v2.2.5

### InsecureSNI removal

In `v2.2.2` we introduced a new flag (`insecureSNI`) which was available as a global option to disable domain fronting.
Since `v2.2.5` this global option has been removed, and you should not use it anymore.

### HostSNI rule matcher removal

In `v2.2.2` we introduced a new rule matcher (`HostSNI`) for HTTP routers which was allowing to match the Server Name Indication at the router level.
Since `v2.2.5` this rule has been removed for HTTP routers, and you should not use it anymore.

## v2.2 to v2.3

### X.509 CommonName Deprecation

The deprecated, legacy behavior of treating the CommonName field on X.509 certificates as a host name when no Subject Alternative Names are present, is now disabled by default.

It means that if one is using https with your backend servers, and a certificate with only a CommonName,
Traefik will not try to match the server name indication with the CommonName anymore.

It can be temporarily re-enabled by adding the value `x509ignoreCN=0` to the `GODEBUG` environment variable.

More information: https://golang.org/doc/go1.15#commonname

### File Provider

The file parser has been changed, since v2.3 the unknown options/fields in a dynamic configuration file are treated as errors.

### IngressClass

In `v2.3`, the support of `IngressClass`, which is available since Kubernetes version `1.18`, has been introduced.
In order to be able to use this new resource the [Kubernetes RBAC](../reference/dynamic-configuration/kubernetes-crd.md#rbac) must be updated. 

## v2.3 to v2.4

### ServersTransport

In `v2.4.0`, the support of `ServersTransport` has been introduced.
It is therefore necessary to update [RBAC](../reference/dynamic-configuration/kubernetes-crd.md#rbac) and [CRD](../reference/dynamic-configuration/kubernetes-crd.md) definitions.

## v2.4.7 to v2.4.8

### Non-ASCII Domain Names

In `v2.4.8`, we introduced a new check on domain names used in HTTP router rule `Host` and `HostRegexp` expressions,
and in TCP router rule `HostSNI` expression.
This check ensures that provided domain names don't contain non-ASCII characters. 
If not, an error is raised, and the associated router will be shown as invalid in the dashboard.

This new behavior is intended to show what was failing silently previously and to help troubleshooting configuration issues.
It doesn't change the support for non-ASCII domain names in routers rules, which is not part of the Traefik feature set so far.

In order to use non-ASCII domain names in a router's rule, one should use the Punycode form of the domain name.
For more information, please read the [HTTP routers rule](../routing/routers/index.md#rule) part or [TCP router rules](../routing/routers/index.md#rule_1) part of the documentation.

## v2.4.8 to v2.4.9

### Tracing Span

In `v2.4.9`, we changed span error to log only server errors (>= 500).

## v2.4.9 to v2.4.10

### K8S CrossNamespace

In `v2.4.10`, the default value for `allowCrossNamespace` has been changed to `false`.

### K8S ExternalName Service

In `v2.4.10`, by default, it is no longer authorized to reference Kubernetes ExternalName services.
To allow it, the `allowExternalNameServices` option should be set to `true`.