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### Do you want to request a *feature* or report a *bug*?

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Bug

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The configurations between 1.X and 2.X are NOT compatible.
Please have a look here https://docs.traefik.io/v2.0/getting-started/configuration-overview/.

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### What did you do?

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HOW TO WRITE A GOOD BUG REPORT?

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### What did you expect to see?



### What did you see instead?



### Output of `traefik version`: (_What version of Traefik are you using?_)

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`latest` is not considered as a valid version.

For the Traefik Docker image:
    docker run [IMAGE] version
    ex: docker run traefik version

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```
(paste your output here)
```

### What is your environment & configuration (arguments, toml, provider, platform, ...)?

```toml
# (paste your configuration here)
```

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Add more configuration information here.
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### If applicable, please paste the log output in DEBUG level (`--log.level=DEBUG` switch)

```
(paste your output here)
```
