Common

Syntax#

The following represent common syntax used within the configuration which have specific format requirements that are used in multiple areas. This is intended on assisting in understanding these specific values, and not as a specific guide on configuring any particular instance.

Duration#

The base type for this syntax is a string, and it also handles integers however this is discouraged.

If you supply an integer, it is considered a representation of seconds. If you supply a string, it parses the string in blocks of quantities and units (number followed by a unit letter). For example 5h indicates a quantity of 5 units of h.

The following is ignored or stripped from the input:

• all spaces
• leading zeros
• the word and

While you can use multiple of these blocks in combination, we suggest keeping it simple and use a single value. In addition it’s important to note that the format while somewhat human readable still requires you closely follow the expected formats.

Unit Legend#

The following is a legend for the unit formats available in this syntax. The long form units are only available from v4.38.0 or newer.

Examples#

Address#

The base type for this syntax is a string.

The address type is a string that indicates how to configure a listener (i.e. listening for connections) or connector (i.e. opening remote connections), which are the two primary categories of addresses.

Format#

This section outlines the format for these strings. The formats use a conventional POSIX format to indicate optional and required elements. The square brackets [] surround optional portions, and the angled brackets <> surround required portions. Required portions may exist within optional portions, in which case they are often accompanied with other format specific text which indicates if the accompanying text exists then it is actually required, otherwise it’s entirely optional.

The square brackets indicate optional sections, and the angled brackets indicate required sections. The following sections elaborate on this. Sections may only be optional for the purposes of parsing, there may be a configuration requirement that one of these is provided.

Hostname#

The following format represents the hostname format. It’s valid for both a listener and connector in most instances. Refer to the individual documentation for an option for clarity. In this format as per the notation the scheme and port are optional. The default for these when not provided varies.

[<scheme>://]<hostname>[:<port>][/<path>]

Port#

The following format represents the port format. It’s valid only for a listener in most instances. Refer to the individual documentation for an option for clarity. In this format as per the notation the scheme and hostname are optional. The default for the scheme when not provided varies, and the default for the hostname is all available addresses when not provided.

[<scheme>://][hostname]:<port>[/<path>]

Unix Domain Socket#

The following format represents the unix domain socket format. It’s valid for both a listener and connector in most instances. Refer to the individual documentation for an option for clarity. In this format as per the notation there are no optional portions.

The Unix Domain Socket format also accepts a query string. The following query parameters control certain behavior of this address type.

unix://<path>

unix://<path>?umask=0022

unix://<path>?path=auth

unix://<path>?umask=0022&path=auth

Examples#

Various examples for these formats.

0.0.0.0
tcp://0.0.0.0
tcp://0.0.0.0/subpath
tcp://0.0.0.0:9091
tcp://0.0.0.0:9091/subpath
tcp://:9091
tcp://:9091/subpath
0.0.0.0:9091

udp://0.0.0.0:123
udp://:123

unix:///var/lib/authelia.sock

scheme#

The entire scheme is optional, but if the scheme host delimiter :// is in the string, the scheme must be present. The scheme must be one of the following (the listeners and connectors columns indicate support for the scheme on the respective address type):

If the scheme is absent, the default scheme is assumed. If the address has a / prefix it’s assumed to be unix, otherwise it’s assumed to betcp. If the scheme is unix it must be suffixed with an absolute path i.e. /var/local/authelia.sock would be represented as unix:///var/run/authelia.sock.

hostname#

The hostname is required if the scheme is one of the tcp or udp schemes and there is no port specified. It can be any IP that is locally addressable or a hostname which resolves to a locally addressable IP.

If specifying an IPv6 it should be wrapped in square brackets. For example for the IPv6 address ::1 with the tcp scheme and port 80 the correct address would be tcp://[::1]:80.

port#

The hostname is required if the scheme is one of the tcp or udp schemes and there is no hostname specified.

Regular Expressions#

We have several sections of configuration that utilize regular expressions. We use the Google RE2 regular expression engine which is the full Go regular expression syntax engine, the syntax of which is described here by the authors. It’s very similar to regular expression engines like PCRE, Perl, and Python; with the major exceptions being that it doesn’t have backtracking.

It’s recommended to validate your regular expressions manually either via tools like Regex 101 (ensure you pick the Golang option) or some other means.

It’s important when attempting to utilize a backslash that it’s utilized correctly. The YAML parser is likely to parse this as you trying to use YAML escape syntax instead of regex escape syntax. To avoid this use single quotes instead of no quotes or double quotes.

Good Example:

domain_regex: '^(admin|secure)\.example\.com$'

Bad Example:

domain_regex: "^(admin|secure)\.example\.com$"

Structures#

The following represent common data structures used within the configuration which have specific requirements that are used in multiple areas. This is intended on assisting in understanding these specific structures, and not as a specific guide on configuring any particular instance.

TLS#

Various sections of the configuration use a uniform configuration section called TLS. Notably LDAP and SMTP. This section documents the usage.

Various sections of the configuration use a uniform configuration section called tls which configure TLS socket and TLS verification parameters. Notably the LDAP, SMTP, PostgreSQL, MySQL, and Redis sections. This section documents the common parts of this structure.

tls:
  server_name: 'example.com'
  skip_verify: false
  minimum_version: 'TLS1.2'
  maximum_version: 'TLS1.3'
  certificate_chain: |
    -----BEGIN CERTIFICATE-----
    ...
    -----END CERTIFICATE-----
    -----BEGIN CERTIFICATE-----
    ...
    -----END CERTIFICATE-----    
  private_key: |
    -----BEGIN RSA PRIVATE KEY-----
    ...
    -----END RSA PRIVATE KEY-----    

server_name#

The key server_name overrides the name checked against the certificate in the verification process. Useful if you require an IP address for the host of the backend service but want to verify a specific certificate server name.

skip_verify#

The key skip_verify completely negates validating the certificate of the backend service. This is not recommended, instead you should tweak the server_name option, and the global option certificates directory.

minimum_version#

Controls the minimum TLS version Authelia will use when performing TLS handshakes. The possible values are TLS1.3, TLS1.2, TLS1.1, TLS1.0, SSL3.0. Anything other than TLS1.3 or TLS1.2 are very old and deprecated. You should avoid using these and upgrade your backend service instead of decreasing this value. At the time of this writing SSL3.0 will always produce errors.

maximum_version#

Controls the maximum TLS version Authelia will use when performing TLS handshakes. The possible values are TLS1.3, TLS1.2, TLS1.1, TLS1.0, SSL3.0. Anything other than TLS1.3 or TLS1.2 are very old and deprecated. You should avoid using these and upgrade your backend service instead of decreasing this value. At the time of this writing SSL3.0 will always produce errors.

certificate_chain#

The certificate chain/bundle to be used with the private_key to perform mutual TLS authentication with the server.

The value must be one or more certificates encoded in the DER base64 (RFC4648) encoded PEM format. If more than one certificate is provided, in top down order, each certificate must be signed by the next certificate if provided.

private_key#

Important Note: This can also be defined using a secret which is strongly recommended especially for containerized deployments.

The private key to be used with the certificate_chain for mutual TLS authentication. The public key material of the private key must match the private key of the first certificate in the certificate_chain.

The value must be one private key encoded in the DER base64 (RFC4648) encoded PEM format and must be encoded per the PKCS#8, PKCS#1, or SECG1 specifications.

Server Buffers#

Various sections of the configuration use a uniform configuration section called buffers which configure HTTP server buffers. Notably the server and metrics telemetry sections. This section documents the common parts of this structure.

buffers:
  read: 4096
  write: 4096

read#

Configures the maximum request size. The default of 4096 is generally sufficient for most use cases.

write#

Configures the maximum response size. The default of 4096 is generally sufficient for most use cases.

Server Timeouts#

Various sections of the configuration use a uniform configuration section called timeouts which configure HTTP server timeouts. Notably the server and metrics telemetry sections. This section documents the common parts of this structure.

timeouts:
  read: '6s'
  write: '6s'
  idle: '30s'

read#

Configures the server read timeout.

write#

Configures the server write timeout.

idle#

Configures the server idle timeout.

Historical References#

This contains links to historical anchors.

Duration Notation Format#

See duration common syntax.