| `<prefix>.backend.circuitbreaker.expression=EXPR` | Create a [circuit breaker](/basics/#backends) to be used against the backend. ex: `NetworkErrorRatio() > 0.` |
| `<prefix>.backend.healthcheck.path=/health` | Enable health check for the backend, hitting the container at `path`. |
| `<prefix>.backend.healthcheck.port=8080` | Allow to use a different port for the health check. |
| `<prefix>.backend.healthcheck.interval=1s` | Define the health check interval. |
| `<prefix>.backend.maxconn.amount=10` | Set a maximum number of connections to the backend.<br>Must be used in conjunction with the below label to take effect. |
| `<prefix>.backend.maxconn.extractorfunc=client.ip` | Set the function to be used against the request to determine what to limit maximum connections to the backend by.<br>Must be used in conjunction with the above label to take effect. |
| `<prefix>.frontend.auth.basic=EXPR` | Sets basic authentication for that frontend in CSV format: `User:Hash,User:Hash` |
| `<prefix>.frontend.entryPoints=http,https` | Assign this frontend to entry points `http` and `https`.<br>Overrides `defaultEntryPoints` |
| `<prefix>.frontend.errors.<name>.backend=NAME` | See [custom error pages](/configuration/commons/#custom-error-pages) section. |
| `<prefix>.frontend.errors.<name>.query=PATH` | See [custom error pages](/configuration/commons/#custom-error-pages) section. |
| `<prefix>.frontend.errors.<name>.status=RANGE` | See [custom error pages](/configuration/commons/#custom-error-pages) section. |
| `<prefix>.frontend.passHostHeader=true` | Forward client `Host` header to the backend. |
| `<prefix>.frontend.passTLSCert=true` | Forward TLS Client certificates to the backend. |
| `<prefix>.frontend.redirect.regex=^http://localhost/(.*)` | Redirect to another URL for that frontend.<br>Must be set with `traefik.frontend.redirect.replacement`. |
| `<prefix>.frontend.redirect.replacement=http://mydomain/$1` | Redirect to another URL for that frontend.<br>Must be set with `traefik.frontend.redirect.regex`. |
| `<prefix>.frontend.whiteList.sourceRange=RANGE` | List of IP-Ranges which are allowed to access.<br>An unset or empty list allows all Source-IPs to access. If one of the Net-Specifications are invalid, the whole list is invalid and allows all Source-IPs to access. |
| `<prefix>.frontend.whiteList.useXForwardedFor=true` | Use `X-Forwarded-For` header as valid source of IP for the white list. |
| `<prefix>.frontend.headers.customRequestHeaders=EXPR ` | Provides the container with custom request headers that will be appended to each request forwarded to the container.<br>Format: <code>HEADER:value||HEADER2:value2</code> |
| `<prefix>.frontend.headers.customResponseHeaders=EXPR` | Appends the headers to each response returned by the container, before forwarding the response to the client.<br>Format: <code>HEADER:value||HEADER2:value2</code> |
| `<prefix>.frontend.headers.hostsProxyHeaders=EXPR` | Provides a list of headers that the proxied hostname may be stored.<br>Format: `HEADER1,HEADER2` |
| `<prefix>.frontend.headers.SSLRedirect=true` | Forces the frontend to redirect to SSL if a non-SSL request is sent. |
| `<prefix>.frontend.headers.SSLTemporaryRedirect=true` | Forces the frontend to redirect to SSL if a non-SSL request is sent, but by sending a 302 instead of a 301. |
| `<prefix>.frontend.headers.SSLHost=HOST` | This setting configures the hostname that redirects will be based on. Default is "", which is the same host as the request. |
| `<prefix>.frontend.headers.SSLProxyHeaders=EXPR` | Header combinations that would signify a proper SSL Request (Such as `X-Forwarded-For:https`).<br>Format: <code>HEADER:value||HEADER2:value2</code> |
| `<prefix>.frontend.headers.STSSeconds=315360000` | Sets the max-age of the STS header. |
| `<prefix>.frontend.headers.STSIncludeSubdomains=true` | Adds the `IncludeSubdomains` section of the STS header. |
| `<prefix>.frontend.headers.STSPreload=true` | Adds the preload flag to the STS header. |
| `<prefix>.frontend.headers.forceSTSHeader=false` | Adds the STS header to non-SSL requests. |
| `<prefix>.frontend.headers.frameDeny=false` | Adds the `X-Frame-Options` header with the value of `DENY`. |
| `<prefix>.frontend.headers.customFrameOptionsValue=VALUE` | Overrides the `X-Frame-Options` header with the custom value. |
| `<prefix>.frontend.headers.contentTypeNosniff=true` | Adds the `X-Content-Type-Options` header with the value `nosniff`. |
| `<prefix>.frontend.headers.browserXSSFilter=true` | Adds the X-XSS-Protection header with the value `1; mode=block`. |
| `<prefix>.frontend.headers.customBrowserXSSValue=VALUE` | Set custom value for X-XSS-Protection header. This overrides the BrowserXssFilter option. |
| `<prefix>.frontend.headers.isDevelopment=false` | This will cause the `AllowedHosts`, `SSLRedirect`, and `STSSeconds`/`STSIncludeSubdomains` options to be ignored during development.<br>When deploying to production, be sure to set this to false. |
### Examples
If you want that Træfik uses Consul tags correctly you need to defined them like that:
