Configuration Details for Migrating from Traefik v2 to v3¶

Static Configuration Changes¶

SwarmMode¶

In v3, the provider Docker has been split into 2 providers:

Docker provider (without Swarm support)
Swarm provider (Swarm support only)

An example usage of v2 Docker provider with Swarm

File (YAML)

providers:
  docker:
    swarmMode: true

File (TOML)

[providers.docker]
    swarmMode=true

CLI

--providers.docker.swarmMode=true

This configuration is now unsupported and would prevent Traefik to start.

Remediation¶

In v3, the swarmMode should not be used with the Docker provider, and, to use Swarm, the Swarm provider should be used instead.

An example usage of the Swarm provider

File (YAML)

providers:
  swarm:
    endpoint: "tcp://127.0.0.1:2377"

File (TOML)

[providers.swarm]
    endpoint="tcp://127.0.0.1:2377"

CLI

--providers.swarm.endpoint=tcp://127.0.0.1:2377

TLS.CAOptional¶

Docker provider tls.CAOptional option has been removed in v3, as TLS client authentication is a server side option (see https://pkg.go.dev/crypto/tls#ClientAuthType).

An example usage of the TLS.CAOptional option

File (YAML)

providers:
  docker:
    tls: 
      caOptional: true

File (TOML)

[providers.docker.tls]
    caOptional=true

CLI

--providers.docker.tls.caOptional=true

Remediation¶

The tls.caOptional option should be removed from the Docker provider static configuration.

Kubernetes Gateway API¶

Experimental Channel Resources (TLSRoute and TCPRoute)¶

In v3, the Kubernetes Gateway API provider does not enable support for the experimental channel API resources by default.

Remediation¶

The experimentalChannel option should be used to enable the support for the experimental channel API resources.

An example usage of the Kubernetes Gateway API provider with experimental channel support enabled

File (YAML)

providers:
  kubernetesGateway:
    experimentalChannel: true

File (TOML)

[providers.kubernetesGateway]
    experimentalChannel = true
  # ...

CLI

--providers.kubernetesgateway.experimentalchannel=true

Experimental Configuration¶

HTTP3¶

In v3, HTTP/3 is no longer an experimental feature. It can be enabled on entry points without the associated experimental.http3 option, which is now removed. It is now unsupported and would prevent Traefik to start.

An example usage of v2 Experimental http3 option

File (YAML)

experimental:
  http3: true

File (TOML)

[experimental]
    http3=true

CLI

--experimental.http3=true

Remediation¶

The http3 option should be removed from the static configuration experimental section. To configure http3, please checkout the entrypoint configuration documentation.

Consul provider¶

namespace¶

The Consul provider namespace option was deprecated in v2 and is now removed in v3. It is now unsupported and would prevent Traefik to start.

An example usage of v2 Consul namespace option

File (YAML)

consul:
  namespace: foobar

File (TOML)

[consul]
    namespace=foobar

CLI

--consul.namespace=foobar

Remediation¶

In v3, the namespaces option should be used instead of the namespace option.

An example usage of Consul namespaces option

File (YAML)

consul:
  namespaces:
    - foobar

File (TOML)

[consul]
    namespaces=["foobar"]

CLI

--consul.namespaces=foobar

TLS.CAOptional¶

Consul provider tls.CAOptional option has been removed in v3, as TLS client authentication is a server side option (see https://pkg.go.dev/crypto/tls#ClientAuthType).

An example usage of the TLS.CAOptional option

File (YAML)

providers:
  consul:
    tls: 
      caOptional: true

File (TOML)

[providers.consul.tls]
    caOptional=true

CLI

--providers.consul.tls.caOptional=true

Remediation¶

The tls.caOptional option should be removed from the Consul provider static configuration.

ConsulCatalog provider¶

namespace¶

The ConsulCatalog provider namespace option was deprecated in v2 and is now removed in v3. It is now unsupported and would prevent Traefik to start.

An example usage of v2 ConsulCatalog namespace option

File (YAML)

consulCatalog:
  namespace: foobar

File (TOML)

[consulCatalog]
    namespace=foobar

CLI

--consulCatalog.namespace=foobar

Remediation¶

In v3, the namespaces option should be used instead of the namespace option.

An example usage of ConsulCatalog namespaces option

File (YAML)

consulCatalog:
  namespaces:
    - foobar

File (TOML)

[consulCatalog]
    namespaces=["foobar"]

CLI

--consulCatalog.namespaces=foobar

Endpoint.TLS.CAOptional¶

ConsulCatalog provider endpoint.tls.CAOptional option has been removed in v3, as TLS client authentication is a server side option (see https://pkg.go.dev/crypto/tls#ClientAuthType).

An example usage of the Endpoint.TLS.CAOptional option

File (YAML)

providers:
  consulCatalog:
    endpoint:
      tls: 
        caOptional: true

File (TOML)

[providers.consulCatalog.endpoint.tls]
    caOptional=true

CLI

--providers.consulCatalog.endpoint.tls.caOptional=true

Remediation¶

The endpoint.tls.caOptional option should be removed from the ConsulCatalog provider static configuration.

Nomad provider¶

namespace¶

The Nomad provider namespace option was deprecated in v2 and is now removed in v3. It is now unsupported and would prevent Traefik to start.

An example usage of v2 Nomad namespace option

File (YAML)

nomad:
  namespace: foobar

File (TOML)

[nomad]
    namespace=foobar

CLI

--nomad.namespace=foobar

Remediation¶

In v3, the namespaces option should be used instead of the namespace option.

An example usage of Nomad namespaces option

File (YAML)

nomad:
  namespaces:
    - foobar

File (TOML)

[nomad]
    namespaces=["foobar"]

CLI

--nomad.namespaces=foobar

Endpoint.TLS.CAOptional¶

Nomad provider endpoint.tls.CAOptional option has been removed in v3, as TLS client authentication is a server side option (see https://pkg.go.dev/crypto/tls#ClientAuthType).

An example usage of the Endpoint.TLS.CAOptional option

File (YAML)

providers:
  nomad:
    endpoint:
      tls: 
        caOptional: true

File (TOML)

[providers.nomad.endpoint.tls]
    caOptional=true

CLI

--providers.nomad.endpoint.tls.caOptional=true

Remediation¶

The endpoint.tls.caOptional option should be removed from the Nomad provider static configuration.

Rancher v1 Provider¶

In v3, the Rancher v1 provider has been removed because Rancher v1 is no longer actively maintained, and Rancher v2 is supported as a standard Kubernetes provider.

An example of Traefik v2 Rancher v1 configuration

File (YAML)

providers:
  rancher: {}

File (TOML)

[providers.rancher]

CLI

--providers.rancher=true

This configuration is now unsupported and would prevent Traefik to start.

Remediation¶

Rancher 2.x requires Kubernetes and does not have a metadata endpoint of its own for Traefik to query. As such, Rancher 2.x users should utilize the Kubernetes CRD provider directly.

Also, all Rancher provider related configuration should be removed from the static configuration.

Marathon provider¶

Marathon maintenance ended on October 31, 2021. In v3, the Marathon provider has been removed.

An example of v2 Marathon provider configuration

File (YAML)

providers:
  marathon: {}

File (TOML)

[providers.marathon]

CLI

--providers.marathon=true

This configuration is now unsupported and would prevent Traefik to start.

Remediation¶

All Marathon provider related configuration should be removed from the static configuration.

HTTP Provider¶

TLS.CAOptional¶

HTTP provider tls.CAOptional option has been removed in v3, as TLS client authentication is a server side option (see https://pkg.go.dev/crypto/tls#ClientAuthType).

An example usage of the TLS.CAOptional option

File (YAML)

providers:
  http:
    tls: 
      caOptional: true

File (TOML)

[providers.http.tls]
    caOptional=true

CLI

--providers.http.tls.caOptional=true

Remediation¶

The tls.caOptional option should be removed from the HTTP provider static configuration.

ETCD Provider¶

TLS.CAOptional¶

ETCD provider tls.CAOptional option has been removed in v3, as TLS client authentication is a server side option (see https://pkg.go.dev/crypto/tls#ClientAuthType).

An example usage of the TLS.CAOptional option

File (YAML)

providers:
  etcd:
    tls: 
      caOptional: true

File (TOML)

[providers.etcd.tls]
    caOptional=true

CLI

--providers.etcd.tls.caOptional=true

Remediation¶

The tls.caOptional option should be removed from the ETCD provider static configuration.

Redis Provider¶

TLS.CAOptional¶

Redis provider tls.CAOptional option has been removed in v3, as TLS client authentication is a server side option (see https://pkg.go.dev/crypto/tls#ClientAuthType).

An example usage of the TLS.CAOptional option

File (YAML)

providers:
  redis:
    tls: 
      caOptional: true

File (TOML)

[providers.redis.tls]
    caOptional=true

CLI

--providers.redis.tls.caOptional=true

Remediation¶

The tls.caOptional option should be removed from the Redis provider static configuration.

InfluxDB v1¶

InfluxDB v1.x maintenance ended in 2021. In v3, the InfluxDB v1 metrics provider has been removed.

An example of Traefik v2 InfluxDB v1 metrics configuration

File (YAML)

metrics:
  influxDB: {}

File (TOML)

[metrics.influxDB]

CLI

--metrics.influxDB=true

This configuration is now unsupported and would prevent Traefik to start.

Remediation¶

All InfluxDB v1 metrics provider related configuration should be removed from the static configuration.

Pilot¶

Traefik Pilot is no longer available since October 4^th, 2022.

An example of v2 Pilot configuration

File (YAML)

pilot:
  token: foobar

File (TOML)

[pilot]
    token=foobar

CLI

--pilot.token=foobar

In v2, Pilot configuration was deprecated and ineffective, it is now unsupported and would prevent Traefik to start.

Remediation¶

All Pilot related configuration should be removed from the static configuration.

Operations Changes¶

Traefik RBAC Update¶

In v3, the support of TCPServersTransport has been introduced. When using the KubernetesCRD provider, it is therefore necessary to update RBAC and CRD manifests.

Content-Type Auto-Detection¶

In v3, the Content-Type header is not auto-detected anymore when it is not set by the backend. One should use the ContentType middleware to enable the Content-Type header value auto-detection.

Observability¶

gRPC Metrics¶

In v3, the reported status code for gRPC requests is now the value of the Grpc-Status header.

Tracing¶

In v3, the tracing feature has been revamped and is now powered exclusively by OpenTelemetry (OTel).

Important

Traefik v3 no longer supports direct output formats for specific vendors such as Instana, Jaeger, Zipkin, Haystack, Datadog, and Elastic. Instead, it focuses on pure OpenTelemetry implementation, providing a unified and standardized approach for observability.

Here are two possible transition strategies:

OTLP Ingestion Endpoints:

Most vendors now offer OpenTelemetry Protocol (OTLP) ingestion endpoints. You can seamlessly integrate Traefik v3 with these endpoints to continue leveraging tracing capabilities.
Legacy Stack Compatibility:

For legacy stacks that cannot immediately upgrade to the latest vendor agents supporting OTLP ingestion, using OpenTelemetry (OTel) collectors with appropriate exporters configuration is a viable solution. This allows continued compatibility with the existing infrastructure.

Please check the OpenTelemetry Tracing provider documention for more information.

Internal Resources Observability¶

In v3, observability for internal routers or services (e.g.: ping@internal) is disabled by default. To enable it one should use the new addInternals option for AccessLogs, Metrics or Tracing. Please take a look at the observability documentation for more information:

Dynamic Configuration Changes¶

Router Rule Matchers¶

In v3, a new rule matchers syntax has been introduced for HTTP and TCP routers. The default rule matchers syntax is now the v3 one, but for backward compatibility this can be configured. The v2 rule matchers syntax is deprecated and its support will be removed in the next major version. For this reason, we encourage migrating to the new syntax.

By default, the defaultRuleSyntax static option is automatically set to v3, meaning that the default rule is the new one.

New V3 Syntax Notable Changes¶

The Headers and HeadersRegexp matchers have been renamed to Header and HeaderRegexp respectively.

PathPrefix no longer uses regular expressions to match path prefixes.

QueryRegexp has been introduced to match query values using a regular expression.

HeaderRegexp, HostRegexp, PathRegexp, QueryRegexp, and HostSNIRegexp matchers now uses the Go regexp syntax.

All matchers now take a single value (except Header, HeaderRegexp, Query, and QueryRegexp which take two) and should be explicitly combined using logical operators to mimic previous behavior.

Query can take a single value to match is the query value that has no value (e.g. /search?mobile).

HostHeader has been removed, use Host instead.

Remediation¶

Configure the Default Syntax In Static Configuration¶

The default rule matchers syntax is the expected syntax for any router that is not self opt-out from this default value. It can be configured in the static configuration.

An example configuration for the default rule matchers syntax

File (YAML)

# static configuration
core:
  defaultRuleSyntax: v2

File (TOML)

# static configuration
[core]
    defaultRuleSyntax="v2"

CLI

# static configuration
--core.defaultRuleSyntax=v2

Configure the Syntax Per Router¶

The rule syntax can also be configured on a per-router basis. This allows to have heterogeneous router configurations and ease migration.

An example router with syntax configuration

Docker & Swarm

labels:
  - "traefik.http.routers.test.ruleSyntax=v2"

Kubernetes

apiVersion: traefik.io/v1alpha1
kind: IngressRoute
metadata:
  name: test.route
  namespace: default

spec:
  routes:
    - match: PathPrefix(`/foo`, `/bar`)
      syntax: v2
      kind: Rule

Consul Catalog

- "traefik.http.routers.test.ruleSyntax=v2"

File (YAML)

http:
  routers:
    test:
      ruleSyntax: v2

File (TOML)

[http.routers]
  [http.routers.test]
    ruleSyntax = "v2"

IPWhiteList¶

In v3, we renamed the IPWhiteList middleware to IPAllowList without changing anything to the configuration.

Deprecated Options Removal¶

The tracing.datadog.globaltag option has been removed.
The tls.caOptional option has been removed from the ForwardAuth middleware, as well as from the HTTP, Consul, Etcd, Redis, ZooKeeper, Consul Catalog, and Docker providers.
sslRedirect, sslTemporaryRedirect, sslHost, sslForceHost and featurePolicy options of the Headers middleware have been removed.
The forceSlash option of the StripPrefix middleware has been removed.
The preferServerCipherSuites option has been removed.

TCP LoadBalancer `terminationDelay` option¶

The TCP LoadBalancer terminationDelay option has been removed. This option can now be configured directly on the TCPServersTransport level, please take a look at this documentation

Kubernetes CRDs API Group `traefik.containo.us`¶

In v3, the Kubernetes CRDs API Group traefik.containo.us has been removed. Please use the API Group traefik.io instead.

Kubernetes Ingress API Group `networking.k8s.io/v1beta1`¶

In v3, the Kubernetes Ingress API Group networking.k8s.io/v1beta1 (removed since Kubernetes v1.22) support has been removed.

Please use the API Group networking.k8s.io/v1 instead.

Traefik CRD API Version `apiextensions.k8s.io/v1beta1`¶

In v3, the Traefik CRD API Version apiextensions.k8s.io/v1beta1 (removed since Kubernetes v1.22) support has been removed.

Please use the CRD definition with the API Version apiextensions.k8s.io/v1 instead.

Configuration Details for Migrating from Traefik v2 to v3¶

Static Configuration Changes¶

SwarmMode¶

Remediation¶

TLS.CAOptional¶

Remediation¶

Kubernetes Gateway API¶

Experimental Channel Resources (TLSRoute and TCPRoute)¶

Remediation¶

Experimental Configuration¶

HTTP3¶

Remediation¶

Consul provider¶

namespace¶

Remediation¶

TLS.CAOptional¶

Remediation¶

ConsulCatalog provider¶

namespace¶

Remediation¶

Endpoint.TLS.CAOptional¶

Remediation¶

Nomad provider¶

namespace¶

Remediation¶

Endpoint.TLS.CAOptional¶

Remediation¶

Rancher v1 Provider¶

Remediation¶

Marathon provider¶

Remediation¶

HTTP Provider¶

TLS.CAOptional¶

Remediation¶

ETCD Provider¶

TLS.CAOptional¶

Remediation¶

Redis Provider¶

TLS.CAOptional¶

Remediation¶

InfluxDB v1¶

Remediation¶

Pilot¶

Remediation¶

Operations Changes¶

Traefik RBAC Update¶

Content-Type Auto-Detection¶

Observability¶

gRPC Metrics¶

Tracing¶

Internal Resources Observability¶

Dynamic Configuration Changes¶

Router Rule Matchers¶

New V3 Syntax Notable Changes¶

Remediation¶

Configure the Default Syntax In Static Configuration¶

Configure the Syntax Per Router¶

IPWhiteList¶

Deprecated Options Removal¶

TCP LoadBalancer terminationDelay option¶

Kubernetes CRDs API Group traefik.containo.us¶

Kubernetes Ingress API Group networking.k8s.io/v1beta1¶

Traefik CRD API Version apiextensions.k8s.io/v1beta1¶

TCP LoadBalancer `terminationDelay` option¶

Kubernetes CRDs API Group `traefik.containo.us`¶

Kubernetes Ingress API Group `networking.k8s.io/v1beta1`¶

Traefik CRD API Version `apiextensions.k8s.io/v1beta1`¶