Nginx (nginx)

Master:

Develop:

Installs and configures Nginx web-server

Part of the BAS Ansible Role Collection (BARC)

Overview

• Installs the latest stable version of Nginx from Nginx, or optionally, from system packages instead
• Configures main Nginx configuration file using harmonised defaults from supported operating systems
• Configures additional aspects of Nginx, including: logging, SSL/TLS, security, MIME types, Gzip and caching
• SSL/TLS configuration scores an A+ rating using Qualys SSL Labs SSL Server Test
• Removes default server blocks (virtual hosts) to prevent conflicts
• Configures harmonised structure for server block definition files using sites-available/sites-enabled
• Optionally, configures the system firewall to allow access to Nginx services (HTTP/HTTPS), this is enabled by default
• Provides Ansible templates for generating server blocks for common purposes, including HTTP redirecting to HTTPS

Quality Assurance

This role uses manual and automated testing to ensure the features offered by this role work as advertised. See tests/README.md for more information.

Dependencies

• None

Requirements

• If generating HTTPS server blocks, using templates provided by this role, a valid certificate/private-key

Certificates, and associated private keys, MUST be acquired from a suitable provider and copied to the server for use by Nginx. This role will not perform any of these functions for you, including generating the secure server block definition file. See the usage section for further details on generating server blocks using this role.

• A valid document root

A suitable document root (with or without content) MUST be created, populated for use by Nginx . This role will not perform any of these functions for you, including generating server block definition files. See the usage section for further details on generating server blocks using this role.

Limitations

• Some variables in this role cannot be easily overridden

This specifically affects: webserver_virtual_hosts_tls_certificate_path, webserver_virtual_hosts_tls_key_path, nginx_config_core_pid and nginx_config_core_user.

Values for these variables vary on each supported operating system and therefore cannot be defined as variables in defaults/main.yml (which are universal). Ansible does not support conditionally importing additional variables at the same priority of role 'defaults' (i.e. variables defined in defaults/main.yml), therefore these variables must be set in vars/ within this role, and conditionally loaded using the include_vars module.

Variables set at this priority cannot be easily overridden in playbooks (i.e. using the vars option), or in variable files (i.e. using the vars_files option). In fact only 'extra_vars' set on the command line can override variables of this precedence.

Given the nature of these variables, it is not expected likely users will need (or want) to changes the values for these variables, and therefore the difficultly needed to override them is considered an acceptable, and not significant limitation. However, if other variables need to be defined in this way this may need to revisited in the future.

This limitation is NOT considered to be significant. Solutions will NOT be actively pursued. Pull requests to address this will be considered.

See the Ansible Documentation for further details on variable precedence.

See BARC-93 for further details.

• Non-system sources cannot be used for installing Nginx on CentOS

There is no Nginx package available from system package sources on CentOS. Therefore, non-system sources will always be used. If this is unacceptable you MUST use another role.

This limitation is NOT considered to be significant. Solutions will NOT be actively pursued. Pull requests to address this will be considered.

See BARC-94 for further details.

• Firewall rules generated by this role assume a single HTTP port and a single HTTPS will be used

In situations where you configure multiple server blocks to listen on multiple ports (i.e server block A listens on ports 80/443 and server B listens on ports 81/444), the firewall rules, generated by this role within firewall services, will not include additional ports (i.e. only ports 80/443 will be included).

This can be overcome by generating custom firewall services with additional rules allowing extra ports, or modifying the system firewall directly (not recommended). Care must be taken to use unique firewall service names, otherwise this role will clobber firewall service definition files, and firewall configurations.

Though this is relatively simple limitation to fix within templates in this role, it is not a priority, as is BAS projects, each project uses its own web-servers hosted behind a load balancer. Therefore only one server block (for each particular project), and one set of ports, is needed.

This limitation is NOT considered to be significant. Solutions will NOT be actively pursued. Pull requests to address this will be considered.

See BARC-95 for further details.

• Headers set in server blocks cancel out headers set at higher levels

Nginx supports adding arbitrary headers at multiple levels (i.e. core config, HTTP block, server blocks) - however if any headers are set at a lower level, higher level headers will be ignored.

I.e. If you set headers a and b in the HTTP block and then header c in a server block, only header c would be included in the final response.

Because of this limitation, headers MUST NOT be set in server blocks, as numerous headers are set in the HTTP block which are needed to deliver features of this role (security headers for example).

This limitation is considered to be significant. Solutions will be actively pursued. Pull requests to address this will be gratefully considered and given priority.

See the Nagios documentation for more information on this issue.

See BARC-96 for further details.

• Server block definition file templates provided by this role assume server blocks will be the 'default server'

Nginx server blocks can declare they are the 'default server' for their respective listening port (e.g. default server for port 80). Only one server block SHOULD declare this per listening port.

The server block definition file templates provided this role (for all use-cases) hard-code this declaration, and do not make it optional. This means where multiple server blocks are defined, which listen on the same port (i.e. you are using Host based server identification to support multiple servers on a single machine), the templates provided by this role are unsuitable.

To overcome this limitation either the templates provided by this role would need to be modified, or an alternative method will need to be used to generate definition files.

Though this is relatively simple limitation to fix within templates in this role, it is not a priority, as is BAS projects, each project uses its own web-servers hosted behind a load balancer. Therefore only one server block (for each particular project) is needed.

This limitation is NOT considered to be significant. Solutions will NOT be actively pursued. Pull requests to address this will be considered.

See BARC-97 for further details.

• Server blocks named after distribution default server blocks (i.e. same file-name/location) cannot be used

Specifically server blocks cannot be made at any of these paths:

On Ubuntu machines:

• /etc/nginx/sites-available/default

On CentOS machines:

• /etc/nginx/conf.d/default.conf
• /etc/nginx/conf.d/example-ssl.conf

This limitation is NOT considered to be significant. Solutions will NOT be actively pursued. Pull requests to address this will be considered.

See BARC-91 for further details.

• Manual tests are inelegant, requiring uncommenting sections in playbooks and Vagrant

This role has a higher than average number of distinct test scenarios, mostly relating to the different types of server blocks that are used. Each scenario carries a significant overhead as two virtual machines are needed, as well as additional test machines in most circumstances. Running all of these virtual machines at once requires a significant amount of resources, which are typically unavailable.

for this reason, commenting is used to prevent all virtual machines being built by Vagrant, the idea being when running a scenario the relevant VMs will be uncommented. This means the Ansible playbook and inventory need to be suitably structured not to rely on all VMs always being available. This has lead to repetition of some tests for convenience.

Ideally the number of scenarios this role supports would be reduced to a more typical number (2-3), however this is unlikely. Therefore is considered an ongoing issue, but of low importance, since it only affects developers of this role, not end-users.

This limitation is NOT considered to be significant. However solutions will be actively pursued. Pull requests to address this will be considered.

See BARC-92 for further details.

Usage

Non-system packages

It is a convention of BARC roles to use the latest version of packages. Where a suitable non-system package source is available it will be used. Suitable non-system packages require a reputable, maintainer, typically a company or well respected individual. If this is for some reason unsuitable, it is possible to only use system packages by setting the BARC_use_non_system_package_sources variable to false.

Note: As the package policy varies between system and non-system package sources, and between operating systems, the version of installed packages is variable.

Note: In this role, there is no Nginx package available on CentOS without using non-system packages, see the Limitations section for more information.

Firewall configuration

This role assumes the machine it is applied to is using a system firewall. By default this role will generate a firewall service relevant to Nginx and automatically enable and persist this service to allow access to Nginx's services.

Specifically:

• On CentOS machines:
  • A set of firewalld firewall services will be generated
  • Each firewall service will contain rules for a single firewall scenario
  • This service will be enabled persistently
  • The firewall service is reloaded
• On Ubuntu machines:
  • A UFW firewall application will be generated (overriding the default firewall application for Nginx)
  • This application contains rules for all firewall scenarios
  • This application will be enabled
  • The firewall service is reloaded

Custom generated firewall services are used to ensure if custom listening ports are used (i.e. not ports 80/443) rules will reflect the ports that are used.

Multiple firewall scenarios are available within this role:

• nginx-http
  • Enables HTTP connections only on the port set by the nginx_firewall_port_http variable
• nginx-https
  • Enables HTTPS connections only on the port set by the nginx_firewall_port_https variable
• nginx-http-https
  • Enables HTTP connections on the port set by the nginx_firewall_port_http variable
  • Enables HTTPS connections only on the port set by the nginx_firewall_port_https variable

This role will only enable one scenario, set by the webserver_firewall_rule variable. When setting this variable do not include the nginx- prefix (i.e. to use nginx-http set the webserver_firewall_rule variable to http).

Following the principle of least privilege, the minimum number of firewall rules should be enabled. This means if you are only using HTTP server blocks, for example, the nginx-https scenario SHOULD be used over the nginx-http-https scenario. See the Variables section for the scenario enabled by default.

If you do not want this role to manage the system firewall, or no system firewall is used, you MUST skip the BARC_CONFIGURE_FIREWALL tag when using this role.

Note: If you are using BAS maintained operating system images this configuration is fully supported and should be seamless. In other cases additional configuration may be needed depending on how the system firewall has been configured.

Nginx configuration files

Nginx uses a single configuration file, /etc/nginx/nginx.conf, which controls core Nginx settings (such as the user the web-server runs as), web-server features such as Gzip and server blocks (virtual hosts) along with all the various options each of these sections can contain.

To save having to specify all of these configuration in a single file, which would be hard to read, let alone manage using provisioning tools, Nginx supports including additional files, within the main configuration file. These additional files are essentially configuration fragments, just stored in separate files. At run time, Nginx will combine these fragments to create a complete configuration file.

Note: Nginx will not detect changes to its main, or fragment configuration files once started. If changes are made, the Nginx service will need to be reloaded.

Within this role, the use of includes and file fragments is used extensively and is strongly encouraged. Importantly Nginx supports specifying all files at a given path should be included, rather than specifying each specifically by file-name. This means some feature can configure its own configuration options, it its own file, without needing to alter any other files to be included. This makes automatic provisioning significantly easier in terms of this main role not needing to be aware of any of its children (roles which configure specific features).

The following directory structure is used for constructing the Nginx configuration file.

├── conf.d           <-- Contains Module and additional configuration files (directory)
│   ├── http         <-- Contains Additional configuration files for the 'http' module (directory, example)
│   │   ├── *.conf   <-- Additional configuration file
│   └── *.conf       <-- Module configuration file
└── nginx.conf.j2    <-- Main configuration file

Note: Sever blocks are also included in the main configuration, but are discussed in their own section later on.

Note: Unlike Apache, Nginx does not support a concept similar to .htaccess files, everything must be included in the main Nginx configuration file at some point.

Main configuration file

The main Nginx configuration file, /etc/nginx/nginx.conf, is purposely designed to be as minimal as possible. Other than defining process information, this file simply includes *.conf files within /etc/nginx/conf.d/*.conf, termed module configuration files in this role.

Additional configuration options SHOULD NOT be set in this file. Instead such options SHOULD be set within a module configuration file, or an additional configuration file included by a module configuration file.

Module configuration files

Module configuration files are high level configuration options, usually specifying a main directive, such as 'http'. Each module consists of a single module block, such as (for the 'http' module):

http {
    # Module configuration
}

Typically there will only be a single module, 'http' with a configuration file '/etc/nginx/conf.d/http.conf'. Apart from some basic configuration options, this file mainly loads additional configuration files within /etc/nginx/conf.d/http/*.conf and server block definition files within /etc/nginx/sites-enabled/*.

Additional configuration options for the 'http' module (and for other modules, except basic settings) SHOULD NOT be set in module configuration files. Instead such options SHOULD be set within an additional configuration file.

Additional configuration files

Additional configuration files are lower level, feature specific, configuration options, usually focusing on a particular, non-core, feature such as Gzip or TLS/SSL.

Each feature SHOULD be contained in a separate file to allow easy management when using automated provisioning. This role includes a number of 'common' additional configuration files. Others may be added by additional roles.

Additional files included in this role:

• In the 'http' module:

  • logging.conf - Enables access and error logging by default
  • tls.conf - Sets defaults for TLS/SSL connections where used in server blocks
  • mime.conf - Registers MIME types and sets a default
  • content.conf - Sets default character encoding
  • gzip.conf - Enables Gzip compression by default

• In server block templates:

  • meta-files.conf - Suppress logging unsuccessful requests for missing, non-critical, files such as favicons
  • static-caching - Adds caching for various types of static content (images, CSS, JS, etc.)

More information on these additional sections may be provided in other sub-sections in this README.

Note: Server block definitions SHOULD NOT be specified as additional configuration files. Instead, all definition files SHOULD be specified in /etc/nginx/sites-available, with 'enabled' server blocks symbolically linked to /etc/nginx/site-enabled. Server block definitions are discussed in more detail in their own section later on.

Logging

This role includes additional options to:

• Define, explicitly, a 'default' logging format for access logs which is the same as the built-in 'combined' format
• Define a logging filter to prevent successful requests being logged
• Maintain an error log, which will log server errors of severity 'warning' and above
• Maintain an access log, which will only log unsuccessful requests (i.e. 4XX/5XX errors)

MIME types

This role includes additional options to set the list of know MIME types and set a default value.

TLS/SSL configuration

This role includes additional options for improving the, security/robustness and efficiency of secure connections. These additional options give an A+ rating using Qualys SSL Labs SSL Server Test.

Note: These additional options will apply to any server block which enables TLS/SSL support, unless directly overridden.

Note: If you are BAS staff you SHOULD NOT opt-out of these additional options. Instead you should contact the Web & Applications Team or BAS ICT to discuss your requirements.

Custom DH parameters

Part of the TLS/SSL hardening options used in this role include using custom DH parameters. This role uses DP parameters generated by 18F, specifically this file.

More information on the implications this has can be found here.

TLS/SSL certificates

Note: You MUST enable private key material is suitably protected. These ownership and permission settings are recommendations only. You MUST seek professional advice if you are unsure if you are adequately protecting private key material.

Certificates, and their private keys, SHOULD be located in operating system specific conventional defaults:

• On CentOS machines:
  • Certificates will be stored in: /etc/pki/tls/certs
  • Certificate private keys will be stored in: /etc/pki/tls/private
• On Ubuntu machines:
  • Certificates will be stored in: /etc/ssl/certs
  • Certificate private keys will be stored in: /etc/ssl/private

Certificates and private keys SHOULD be stored be owned by the root user with permissions of (0)600.

Note: In future versions of this role, the location of certificates and private keys may be harmonised to the CentOS defaults.

If you are BAS staff, and are using 'core' certificates (i.e. any certificate for the bas.ac.uk domain), you MUST contact the Web & Applications Team or ICT to ensure you are following best practice. Otherwise you SHOULD seek advice if you are at all unsure.

Information Services provides 'core' certificates for the primary BAS domain (www).bas.ac.uk and sub-domains: *.web.bas.ac.uk, *.data.bas.ac.uk, api.bas.ac.uk, etc. This, and certificates for other domains are maintained by the Web & Applications Team. See the BAS Certificate Store project for more information and instructions for using these 'core' certificates.

For other domains, please contact the Web & Applications Team or BAS ICT to discuss your requirements, as there are NERC guidelines applicable to purchasing certificates.

Security headers

This role includes additional options improving security in terms of how resources from this server can be used. See templates/etc/nginx/conf.d/http/security.conf.j2 for more information.

Default character encoding

This role includes additional options for setting utf-8 as the default character encoding.

Gzip

This role includes additional options for configuring Gzip compression.

The range of mime types to be compressed are set by the webserver_config_gzip_types variable. Other basic options are set in the included configuration file.

Note: Small files will not be Gzipped as the size saving is negligible and a waste of server resources.

Note: As 'chunked' transfer encoding is used for Gzipped content no 'content-length' header will be set.

Note: Image formats are intentionally excluded from Gzip compression as these formats SHOULD be compressed already, in many cases applying Gzip to an already compressed file will only increase the file size.

Gzip with TLS

Due to known vulnerabilities [1] with combining Gzip with TLS, this role disables Gzip in included secure server block templates. This is a precautionary measure and may not be sufficiently concerning in all situations, compared to the missed benefits Gzip brings.

It is therefore your decision whether to use Gzip with TLS, however you should ensure you are fully aware of the consequences in doing so. If you wish to do so, set the nginx_server_blocks_tls_enable_gzip variable to "on".

If you are BAS staff, contact the Web & Applications Team or BAS ICT to discuss your requirements.

[1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=773332

Server Blocks (Virtual Hosts)

Server blocks, known generically as Virtual Hosts in Apache, specify 'servers' which will listen on a set of ports and process requests. Server blocks can be named, if multiple websites are hosted on a single machine. Less commonly, different ports can be used for each 'server' to avoid using names.

Each server block can perform a variety of roles, for example serving a static website, dynamic content using a CGI proxy, or reverse proxying requests to another application, such as Tomcat. Features such as authentication, caching and resource pooling can be used alongside any of these roles as needed.

Each 'server' consists of a server block, which is simply:

server {
    # Server configuration
}

Each server block SHOULD be specified in its own file in /etc/nginx/sites-available/. Server blocks which should be used MUST be symbolically linked to /etc/nginx/sites-enabled/. Requiring this extra step allows easy control over which servers are used, without having to comment out definitions files or moving definition files elsewhere.

You SHOULD read these resources if you are using 'custom' server blocks:

• Common pitfalls to avoid common mistakes
• Nginx directly for pre-written samples for a range of use-cases

Note: This role does not manage server block definitions directly. Templates, discussed later, for generating common server blocks are provided by this role, but tasks to generate them and manage document roots, certificates, etc. need to be implemented outside of this role.

Note: Server block definition files MUST NOT use a file extension or they won't be included in the Nginx configuration file, even when enabled.

Note: Server block definitions MUST NOT set headers as this will 'cancel out' headers set by other parts of the Nginx configuration, see the limitations section for more information.

Note: Don't name definition files with any of these, exact, names as this role will remove them (these are default definitions installed by Nginx, but which when enabled, may cause conflicts):

On Ubuntu machines:

• /etc/nginx/sites-available/default

On CentOS machines:

• /etc/nginx/conf.d/default.conf
• /etc/nginx/conf.d/example-ssl.conf

See the limitations section for more information.

Server block templates

Despite the wide range of possible roles for 'servers', typically roles are not that unique. This role therefore provides a set of Ansible templates for generating server blocks for these common roles.

Note: Remember this role does not directly manage server blocks, it simply provides templates for use in external tasks.

These templates purposely do not cater to every role and use-case, there are simply too many. Therefore it is expected server blocks, not based on templates from this role, will be used as needed. This role will therefore not interfere with server blocks, regardless of whether they are based on templates from this role or not.

Templates provided by this role are located in templates/etc/nginx/sites-available/, examples of using them are shown in the Typical Playbook sub-section. A summary is provided in each template, though it should be fairly obvious what is happening by reading each file.

Server block templates are configured to include relevant additional configuration files, see the Additional configuration files sub-section for more information.

Document root

Document roots should be accessible to the web-server group (www-data on Ubuntu machines, nginx on CentOS), with permissions (0)775 (recursive) recommended for directories and (0)664 for files.

Note: Depending on your use case these recommended permissions may not be suitable. If in doubt use common sense when setting permissions. If you are handling any sensitive information, and you are BAS staff, contact the Web & Applications Team or ICT for additional guidance.

Note: If using server-block templates from this role, ensure the document root exists and has the correct permissions and ownership before generating the template.

TLS certificates

See the Typical playbook section for examples of tasks to do this.

Note: If using server-block templates from this role, ensure any certificates and private keys have been uploaded to the machine with the correct permissions and ownership. See the TLS/SSL certificates sub-section for more information.

Meta files

Some clients, mostly web-browsers, will make requests for a conventional, meta, files such as favicon or robots.txt. This role includes an additional configuration file, server-blocks/meta-files.conf, to suppress logging unsuccessful requests for these files where they are missing.

See templates/etc/nginx/conf.d/server-blocks/meta-files.conf.j2 in this role for a list of meta files covered.

Note: This additional configuration does not prevent these meta files being used, it simply ignores errors where they don't.

Note: If using server-block templates from this role, this additional configuration file will be included automatically. To prevent this, copy the relevant template and adjust the include statement as necessary. Custom server-blocks can include this additional configuration file directly if desired.

Static caching

This role includes additional options for configuring the caching of static content.

This includes: images, audio, video, web-fonts RSS feeds, CSS and JS. Various cache times are used for each media type.

Known dynamic content is explicitly excluded from caching, this includes: HTML, XML and JSON. You can adjust this if needed, or perform caching at a lower or higher level (within applications, or using a caching layer, respectively).

Note: By default CSS and JS will be cached for 1 year. 'Cache-busting' will therefore be needed if CSS/JS are expected to change during this time. Various build tools and frameworks can automate this process if needed.

Note: If using server-block templates from this role, this additional configuration file will be included automatically. To prevent this, copy the relevant template and adjust the include statement as necessary. Custom server-blocks can include this additional configuration file directly if desired.

ETags

Nginx will by default set ETags for content it serves, meaning, in most cases, changes to files will automatically invalidate caching. This means techniques such as 'cache-busting' should not be needed.

For example, you have a 'main.css' file with a cache time of 1 year. A client requests this file on 01/01/2010 and you then update the file on 04/04/2010. The client conditionally requests the file again on 06/06/2010, passing the ETag of the file it has previously cached. As the file has since been changed the ETags do not match and the updated file is returned, instead of a '304 Not Changed' response. This updated file is then cached as normal and used until the ETag changes again, or the cache period is exceeded.

Typical playbook

---

# Playbook for a non-secure web-server
# I.e. for an app server sitting behind a load balancer performing TLS/SSL termination
- name: setup nginx web-server and server block for application
  hosts: all
  become: yes
  vars:
    webserver_virtual_hosts_document_root: /app/public
  roles:
    - BARC.nginx
  tasks:
    - name: generate server block definition files
      template:
         src="roles/nginx/templates/etc/nginx/sites-available/server-http.j2"
        dest="/etc/nginx/sites-available/app-http"
    - name: enable server block definition files
      file:
          src="/etc/nginx/sites-available/app-http"
         dest="/etc/nginx/sites-enabled/app-http"
        state=link
      notify: Restart Nginx
    handlers:
      - include: roles/nginx/handlers/main.yml

# Playbook for a secure web-server
# I.e. for a standalone server exposed directly to the public internet
# Real certificates would obviously normally be used
- name: setup nginx web-server and secure server block for application
  hosts: all
  become: yes
  vars:
    webserver_virtual_hosts_document_root: /app/public
    webserver_virtual_hosts_tls_certificate_file: tls-cert-snakeoil.crt
    webserver_virtual_hosts_tls_key_file: tls-cert-snakeoil.key
  roles:
    - BARC.nginx
  tasks:
    - name: copy and secure snake-oil certificate file and key for testing
      copy:
        src="{{ item.source }}"
        dest="{{ item.dest }}"
        mode=0600
      with_items:
        -
          source: certificates/snakeoil/tls-cert-snakeoil.crt
          dest: "{{ webserver_virtual_hosts_tls_certificate_path }}/{{ webserver_virtual_hosts_tls_certificate_file }}"
        -
          source: certificates/snakeoil/tls-cert-snakeoil.key
          dest: "{{ webserver_virtual_hosts_tls_certificate_path }}/{{ webserver_virtual_hosts_tls_key_file }}"
    - name: generate server block definition files
      template:
         src="roles/nginx/templates/etc/nginx/sites-available/{{ item.src }}.j2"
        dest="/etc/nginx/sites-available/{{ item.dest }}"
      with_items:
        -
          src: server-block-http-to-https
          dest: app-http-redirect
        -
          src: server-block-https
          dest: app-https
    - name: enable server block definition files
      file:
          src="/etc/nginx/sites-available/{{ item }}"
         dest="/etc/nginx/sites-enabled/{{ item }}"
        state=link
      with_items:
        - app-http-redirect
        - app-https
      notify: Restart Nginx
    handlers:
      - include: roles/nginx/handlers/main.yml

Tags

BARC roles use standardised tags to control which aspects of an environment are changed by roles. Where relevant, tags will be applied at a role, or task(s) level, as indicated below.

This role uses the following tags, for various tasks:

• BARC_CONFIGURE
• BARC_CONFIGURE_PACKAGE
• BARC_CONFIGURE_FIREWALL
• BARC_INSTALL
• BARC_INSTALL_PACKAGES

Variables

BARC_use_non_system_package_sources

• MAY be specified
• Specifies whether non-system sources can be used to install packages
• Note: This variable is scoped to all other BARC roles which install packages from non-system sources
• Values MUST use one of these options, as determined by Ansible:
  • true
  • false
• Values SHOULD NOT be quoted to prevent Ansible coercing values to a string
• Where not specified, a value of true will be assumed
• Default: true

os_tls_certificates_path

• MAY be specified
• Species the path to the directory used for containing TLS certificate files, as determined by the operating system
• Values MUST be a valid system path, as determined by the operating system
• Values MUST NOT include a trailing slash (/)
• Values MUST use absolute paths
• The default value, which varies depending on the machine operating system, is a conventional default, other values SHOULD NOT be used without good reason
• The default value for this variable is set as a role variable, rather than a role default variable, this has implications if overriding this value, see the Limitations section for more information
• Default:
  • /etc/pki/tls/certs - CentOS
  • /etc/ssl/certs - Ubuntu

os_tls_keys_path

• MAY be specified
• Species the path to the directory used for containing TLS certificate private key files, as determined by the operating system
• Values MUST be a valid system path, as determined by the operating system
• Values MUST NOT include a trailing slash (/)
• Values MUST use absolute paths
• The default value, which varies depending on the machine operating system, is a conventional default, other values SHOULD NOT be used without good reason
• The default value for this variable is set as a role variable, rather than a role default variable, this has implications if overriding this value, see the Limitations section for more information
• Default:
  • /etc/pki/tls/private - CentOS
  • /etc/ssl/private - Ubuntu

webserver_listening_port_http

• MAY be specified
• Specifies the port on which web-servers will listen for non-secure (HTTP) requests
• Values MUST be a valid system port, as determined by the operating system
• The default value, 80, is a conventional default, other values SHOULD NOT be used without good reason
• Default: 80

webserver_listening_port_https

• MAY be specified
• Specifies the port on which web-servers will listen for secure (HTTPS) requests
• Values MUST be a valid system port, as determined by the operating system
• The default value, 443, is a conventional default, other values SHOULD NOT be used without good reason
• Default: 443

webserver_firewall_rule

• SHOULD be specified
• Specifies the name of the firewall rule to be enabled to allow access to web-server services
• See the Firewall configuration section for more information on how to set this variable
• Values MUST be a valid system firewall service, as determined by the operating system firewall
• Default: http-https

webserver_config_gzip_types

• MAY be specified
• Specifies a list of MIME types Gzip compression will be applied to
• Structured as a list of items, with each item having the following properties:
  • Item values MUST be valid MIME types, as determined by the web server
• Defaults:

- text/plain
- text/css
- text/xml
- application/xml
- application/xml+rss
- application/rss+xml
- text/javascript
- application/x-javascript

webserver_virtual_hosts_listening_port_http

• MAY be specified
• Specifies the port on which virtual hosts will listen for non-secure (HTTP) requests
• Values MUST be a valid system port, as determined by the operating system
• Values MUST be unique for each virtual host where the value of webserver_virtual_hosts_server_name is the same
• By default, the value of this variable is inherited from the webserver_listening_port_http variable
• The fallback value, 80, is a conventional default, it will be used where this variable is not defined
• Default: {{ webserver_listening_port_http | default('80') }}

webserver_virtual_hosts_listening_port_https

• MAY be specified
• Specifies the port on which virtual hosts will listen for secure (HTTPS) requests
• Values MUST be a valid system port, as determined by the operating system
• Values MUST be unique for each virtual host where the value of webserver_virtual_hosts_server_name is the same
• By default, the value of this variable is inherited from the webserver_listening_port_https variable
• The fallback value, 443, is a conventional default, it will be used where this variable is not defined
• Default: {{ webserver_listening_port_https | default('443') }}

webserver_virtual_hosts_server_name

• MAY be specified where the value is suitably generic, otherwise this SHOULD NOT be specified
• This variable is undefined (commented out) by default to allow implementation specific defaults to be used, however if the value for the nginx_server_blocks_server_name variable is a universal value, this variable should be defined (uncommented) will be used automatically instead
• Specifies the logical name of each virtual host
• Values MUST be valid virtual host server names, as determined by the web server
• Values MUST be unique for each server block where the values of webserver_virtual_hosts_listening_port_http and webserver_virtual_hosts_listening_port_https are the same
• Default: #`` - Undefined variable, with an empty string as its value if defined

webserver_virtual_hosts_document_root

• MAY be specified
• Specifies the logical root of the virtual host
• Values MUST be a valid system path, as determined by the web server
• Values MUST NOT include a trailing slash (/)
• Values SHOULD use absolute paths to avoid confusion
• The default value, /var/www/html, is a conventional default, other values SHOULD NOT be used without good reason
• Default: /var/www/html

webserver_virtual_hosts_document_indexes

• MAY be specified
• Specifies a list of files that will be used as an index document
• Structured as a list of items, with each item having the following properties:
  • Item values MUST be valid file names, including any file extension, as determined by the web server
• The default item values, are conventional defaults, other values SHOULD NOT be used without good reason
• Defaults:

- index.html

webserver_virtual_hosts_tls_certificate_path

• MAY be specified
• Specifies the path to the directory containing the certificate file set by the webserver_virtual_hosts_tls_certificate_file variable
• Values MUST be a valid system path, as determined by the web server
• Values MUST NOT include a trailing slash (/)
• By default, the value of this variable is inherited from the os_tls_certificates_path variable
• Default: {{ os_tls_certificates_path }}

webserver_virtual_hosts_tls_certificate_file

• MAY be specified
• Specifies the file name of the certificate in the directory set by the webserver_virtual_hosts_tls_certificate_path variable
• Values MUST be a valid system file, including any file extension, as determined by the web server
• Default: cert.crt

webserver_virtual_hosts_tls_key_path

• MAY be specified
• Specifies the path to the directory containing the certificate private key file set by the webserver_virtual_hosts_tls_key_file variable
• Values MUST be a valid system path, as determined by the web server
• Values MUST NOT include a trailing slash (/)
• By default, the value of this variable is inherited from the tls_keys_path variable
• Default: {{ tls_keys_path }}

webserver_virtual_hosts_tls_key_file

• MAY be specified
• Specifies the file name of the certificate private key in the directory set by the webserver_virtual_hosts_tls_key_path variable
• Values MUST be a valid system file, including any file extension, as determined by the web server
• Default: cert.key

nginx_config_core_pid

• MAY be specified
• Species the file in which the Nginx process id will be stored
• See Nginx documentation for more information
• Values MUST be a valid system path and file, including any file extension, as determined by Nginx
• Values MUST use absolute paths
• The default value, which varies depending on the machine operating system, is a conventional default, other values SHOULD NOT be used without good reason
• The default value for this variable is set as a role variable, rather than a role default variable, this has implications if overriding this value, see the Limitations section for more information
• Default:
  • /var/run/nginx.pid - CentOS
  • /run/nginx.pid - Ubuntu

nginx_config_core_user

• MAY be specified
• Species the operating system Nginx will run as
• See Nginx documentation for more information
• Values MUST correspond with a valid system user, as determined by the operating system
• The default value, which varies depending on the machine operating system, is a conventional default, other values SHOULD NOT be used without good reason
• The default value for this variable is set as a role variable, rather than a role default variable, this has implications if overriding this value, see the Limitations section for more information
• Default:
  • nginx - CentOS
  • www-data - Ubuntu

nginx_firewall_port_http

• MAY be specified where the related generic variable is unsuitable, otherwise this SHOULD NOT be specified
• Specifies the port on which Nginx will listen for non-secure (HTTP) requests, used for generating firewall rules
• Values MUST be a valid system port, as determined by the operating system
• By default, the value of this variable is inherited from the webserver_listening_port_http variable
• Default: {{ webserver_listening_port_http }}

nginx_firewall_port_https

• MAY be specified where the related generic variable is unsuitable, otherwise this SHOULD NOT be specified
• Specifies the port on which Nginx will listen for secure (HTTPS) requests, used for generating firewall rules
• Values MUST be a valid system port, as determined by the operating system
• By default, the value of this variable is inherited from the webserver_listening_port_https variable
• Default: {{ webserver_listening_port_https }}

nginx_firewall_rule

• MAY be specified where the related generic variable is unsuitable, otherwise this SHOULD NOT be specified
• Specifies the name of the firewall rule to be enabled to allow access to Nginx's services
• See the Firewall configuration section for more information on how to set this variable
• Values MUST be a valid system firewall service, as determined by the operating system firewall
• By default, the value of this variable is partially inherited from the webserver_firewall_rule variable
• Default: nginx-{{ webserver_firewall_rule }}

nginx_config_gzip_enable_gzip

• MAY be specified
• Specifies whether Gzip compression should be applied to responses
• See Nginx documentation for more information
• Values MUST use one of these options, as determined by Nginx:
  • on
  • off
• Values MUST be quoted to prevent Ansible coercing values to True/False which is invalid for this variable
• Default: on

nginx_config_gzip_types

• MAY be specified
• Specifies a list of MIME types Gzip compression will be applied to
• Structured as a list of items, with each item having the following properties:
  • Item values MUST be valid MIME types, as determined by Nginx
• By default, the value of this variable is inherited from the webserver_config_gzip_types variable
• Default: {{ webserver_config_gzip_types }}

nginx_server_blocks_listening_port_http

• MAY be specified where the related generic variable is unsuitable, otherwise this SHOULD NOT be specified
• Specifies the port on which server blocks will listen for non-secure (HTTP) requests
• Values MUST be a valid system port, as determined by the operating system
• Values MUST be unique for each server block where the value of nginx_server_blocks_server_name is the same
• By default, the value of this variable is inherited from the webserver_virtual_hosts_listening_port_http variable
• Default: {{ webserver_virtual_hosts_listening_port_http }}

nginx_server_blocks_listening_port_https

• MAY be specified where the related generic variable is unsuitable, otherwise this SHOULD NOT be specified
• Specifies the port on which server blocks will listen for secure (HTTPS) requests
• Values MUST be a valid system port, as determined by the operating system
• Values MUST be unique for each server block where the value of nginx_server_blocks_server_name is the same
• By default, the value of this variable is inherited from the webserver_virtual_hosts_listening_port_https variable
• Default: {{ webserver_virtual_hosts_listening_port_https }}

nginx_server_blocks_server_name

• MAY be specified where the value for the related generic variable is unsuitable, otherwise this SHOULD NOT be specified
• This variable's generic counterpart, webserver_virtual_hosts_server_name, is undefined (commented out) by default to allow implementation specific defaults (this variable) to be used, however if the value for this variable is a universal value, the generic variable should be defined (uncommented) and will be used automatically instead
• Specifies the logical name of the server block
• See Nginx documentation for more information
• Values MUST be valid server block server names, as determined by Nginx
• Values MUST be unique for each server block where the values of nginx_server_blocks_listening_port_http and nginx_server_blocks_listening_port_https are the same
• By default, the value of this variable is inherited from the webserver_virtual_hosts_server_name variable
• The fallback value, _, will be used where this variable is not defined
• Default: {{ webserver_virtual_hosts_server_name | default('_') }}

nginx_server_blocks_root

• MAY be specified where the related generic variable is unsuitable, otherwise this SHOULD NOT be specified
• Specifies the logical root of the server block
• See Nginx documentation for more information
• Values MUST be a valid system path, as determined by Nginx
• Values MUST NOT include a trailing slash (/)
• Values MUST use absolute paths
• By default, the value of this variable is inherited from the webserver_virtual_hosts_document_root variable
• Default: {{ webserver_virtual_hosts_document_root }}

nginx_server_blocks_indexes

• MAY be specified where the related generic variable is unsuitable, otherwise this SHOULD NOT be specified
• Specifies a list of files that will be used as an index document
• See Nginx documentation for more information
• Structured as a list of items, with each item having the following properties:
  • Item values MUST be valid file names, including any extension, as determined by Nginx
• By default, the values of this variable are inherited from the webserver_virtual_hosts_document_indexes variable
• Default: {{ webserver_virtual_hosts_document_indexes }}

nginx_server_blocks_tls_certificate_path

• MAY be specified where the related generic variable is unsuitable, otherwise this SHOULD NOT be specified
• Specifies the path to the directory containing the certificate file set by the nginx_server_blocks_tls_certificate_file variable
• Values MUST be a valid system path, as determined by Nginx
• Values MUST NOT include a trailing slash (/)
• By default, the value of this variable is inherited from the webserver_virtual_hosts_tls_certificate_path variable
• Default: {{ webserver_virtual_hosts_tls_certificate_path }}

nginx_server_blocks_tls_certificate_file

• MAY be specified where the related generic variable is unsuitable, otherwise this SHOULD NOT be specified
• Specifies the file name of the certificate in the directory set by the nginx_server_blocks_tls_certificate_path variable
• Values MUST be a valid system file, including any file extension, as determined by Nginx
• By default, the value of this variable is inherited from the webserver_virtual_hosts_tls_certificate_file variable
• Default: {{ webserver_virtual_hosts_tls_certificate_file }}

nginx_server_blocks_tls_key_path

• MAY be specified where the related generic variable is unsuitable, otherwise this SHOULD NOT be specified
• Specifies the path to the directory containing the certificate private key file set by the nginx_server_blocks_tls_key_file variable
• Values MUST be a valid system path, as determined by Nginx
• Values MUST NOT include a trailing slash (/)
• By default, the value of this variable is inherited from the webserver_virtual_hosts_tls_key_path variable
• Default: {{ webserver_virtual_hosts_tls_key_path }}

nginx_server_blocks_tls_key_file

• MAY be specified where the related generic variable is unsuitable, otherwise this SHOULD NOT be specified
• Specifies the file name of the certificate private key in the directory set by the nginx_server_blocks_tls_key_path variable
• Values MUST be a valid system file, including any file extension, as determined by Nginx
• By default, the value of this variable is inherited from the webserver_virtual_hosts_tls_key_file variable
• Default: {{ webserver_virtual_hosts_tls_key_file }}

nginx_server_blocks_tls_enable_gzip

• MAY be specified
• Specifies whether Gzip compression is enabled using TLS
• See Nginx documentation for more information
• There are specific concerns when using TLS with Gzip, see the Gzip with TLS sub-section for more information
• Values MUST use one of these options, as determined by Nginx:
  • on
  • off
• Values MUST be quoted to prevent Ansible coercing values to True/False which is invalid for this variable
• Default: off

Developing

Issue tracking

Issues, bugs, improvements, questions, suggestions and other tasks related to this package are managed through the BAS Ansible Role Collection (BARC) project on Jira.

This service is currently only available to BAS or NERC staff, although external collaborators can be added on request. See our contributing policy for more information.

Source code

All changes should be committed, via pull request, to the canonical repository, which for this project is:

ssh://git@stash.ceh.ac.uk:7999/barc/nginx.git

A mirror of this repository is maintained on GitHub. Changes are automatically pushed from the canonical repository to this mirror, in a one-way process.

git@github.com:antarctica/ansible-nginx.git

Note: The canonical repository is only accessible within the NERC firewall. External collaborators, please make pull requests against the mirrored GitHub repository and these will be merged as appropriate.

Contributing policy

This project welcomes contributions, see CONTRIBUTING.md for our general policy.

The Git flow workflow is used to manage the development of this project:

• Discrete changes should be made within feature branches, created from and merged back into develop (where small changes may be made directly)
• When ready to release a set of features/changes, create a release branch from develop, update documentation as required and merge into master with a tagged, semantic version (e.g. v1.2.3)
• After each release, the master branch should be merged with develop to restart the process
• High impact bugs can be addressed in hotfix branches, created from and merged into master (then develop) directly

License

Copyright 2015 NERC BAS.

Unless stated otherwise, all documentation is licensed under the Open Government License - version 3. All code is licensed under the MIT license.

Copies of these licenses are included within this role.