feat: flip swap mechanism — MD as primary, RST as override (Phase 1)

This is the first of three phases inverting the per-page swap mechanism
so MD becomes the canonical primary and RST becomes the rare override.

Phase 1 — file renames + conf.py exclude_patterns flip only:
- Rename docs/**/md-<stem>.md to docs/**/<stem>.md (drop md- prefix)
  for all 254 stems previously listed in docs/_swap.txt
- Rename docs/**/<stem>.rst to docs/**/rst-<stem>.rst (add rst- prefix)
  for the same 254 stems
- Repurpose docs/_swap.txt as docs/_rst_overrides.txt; initially empty
  comment-only since no pages need the RST fallback right now
- conf.py exclude_patterns flipped: rst-*.rst is now excluded by default
  instead of md-*.md
- conf.py runtime-artifact references updated to _rst_override_state.json
  and _md_exclude.txt (Phase 2 will rewrite swap_sources.py to produce
  these names; for now no swap script runs because overrides list is empty)

Phase 2 (next commit on this branch) will rewrite scripts/swap_sources.py
with inverted rename direction, delete scripts/import_myst.py + tests, and
update tests/test_swap_sources.py for the new semantics.

Phase 3 will be the cleanup pass and ready-for-review flip.

Generated by robots https://vyos.io

1 files changed, 509 insertions, 0 deletions

diff --git a/docs/configuration/loadbalancing/rst-haproxy.rst b/docs/configuration/loadbalancing/rst-haproxy.rst
new file mode 100644
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+++ b/docs/configuration/loadbalancing/rst-haproxy.rst
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+:lastproofread: 2026-04-06
+
+#############
+HAproxy
+#############
+
+.. include:: /_include/need_improvement.txt
+
+HAProxy is a load balancer and proxy server that provides
+high-availability, load balancing, and proxying for TCP (level 4) and
+HTTP-based (level 7) applications.
+
+Configuration
+=============
+
+
+Service configuration specifies the port to bind to. Backend
+configuration defines the load balancing method and specifies the backend
+servers.
+
+Service
+-------
+
+.. cfgcmd:: set load-balancing haproxy service <name> listen-address
+   <address>
+
+  Set the IP address for the service to bind to. By default, the service
+  listens on all IPv4 and IPv6 addresses.
+
+.. cfgcmd:: set load-balancing haproxy service <name> port
+   <port>
+
+  Create service `<name>` to listen on <port>
+
+.. cfgcmd:: set load-balancing haproxy service <name> mode
+   <tcp|http>
+
+  Configure service `<name>` mode TCP or HTTP
+
+.. cfgcmd:: set load-balancing haproxy service <name> backend
+   <name>
+
+  Configure service `<name>` to use the backend <name>
+
+.. cfgcmd:: set load-balancing haproxy service <name> ssl
+   certificate <name>
+
+  Set the SSL certificate <name> for service <name>. You can define
+  multiple certificates.
+
+.. cfgcmd:: set load-balancing haproxy service <name>
+  http-response-headers <header-name> value <header-value>
+
+  Set custom HTTP headers to include in all responses.
+
+.. cfgcmd:: set load-balancing haproxy service <name> logging facility
+  <facility> level <level>
+
+  Specify facility and level for logging.
+  For an explanation on :ref:`syslog_facilities` and
+  :ref:`syslog_severity_level`,
+  see tables in the syslog configuration section.
+
+.. cfgcmd:: set load-balancing haproxy service <name> timeout client
+  <seconds>
+
+  Set the maximum inactivity time on the client side for this service.
+  Value range 1-3600 seconds.
+
+.. cfgcmd:: set load-balancing haproxy service <name> http-compression algorithm
+  <gzip | deflate | identity | raw-deflate>
+
+  Set the compression algorithm to be used when compressing HTTP responses.
+
+.. cfgcmd:: set load-balancing haproxy service <name> http-compression mime-type
+  <mime-type>
+
+  Set the list of HTTP response MIME types which haproxy will attempt to
+  compress, if received uncompressed from backend server.
+
+Rules
+^^^^^
+Rules control and route incoming traffic to specific backends based on
+predefined conditions. Rules define matching criteria and specify actions
+to perform.
+
+.. cfgcmd:: set load-balancing haproxy service <name> rule <rule>
+   domain-name <name>
+
+  Match domain name
+
+.. cfgcmd:: set load-balancing haproxy service <name> rule <rule>
+   ssl <sni>
+
+  SSL match Server Name Indication (SNI) option:
+   * ``req-ssl-sni`` SSL Server Name Indication (SNI) request match
+   * ``ssl-fc-sni`` SSL frontend connection Server Name Indication match
+   * ``ssl-fc-sni-end`` SSL frontend match end of connection Server Name 
+      
+      Indication
+
+.. cfgcmd:: set load-balancing haproxy service <name> rule <rule>
+   url-path <match> <url>
+
+  Define URL path matching rules for a specific service. Use this command
+  to specify how to match the URL path against incoming requests.
+
+  The available options for <match> are:
+   * ``begin`` Matches the beginning of the URL path
+   * ``end`` Matches the end of the URL path.
+   * ``exact`` Matches the URL path exactly.
+
+.. cfgcmd:: set load-balancing haproxy service <name> rule <rule>
+   set backend <name>
+
+  Assign a specific backend to a rule
+
+.. cfgcmd:: set load-balancing haproxy service <name> rule <rule>
+   redirect-location <url>
+
+  Redirect URL to a new location.
+
+
+Backend
+-------
+
+.. cfgcmd:: set load-balancing haproxy backend <name> balance
+   <balance>
+
+  Specify the load balancing algorithm for distributing requests among
+  available servers.
+
+  Balance algorithms:
+   * ``source-address`` Distributes requests based on the source IP address
+     of the client.
+   * ``round-robin`` Distributes requests in a circular manner,
+     sequentially sending each request to the next server in line.
+   * ``least-connection`` Distributes requests to the server with the fewest
+     active connections.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> mode
+   <mode>
+
+  Configure backend `<name>` mode TCP or HTTP.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> server
+   <name> address <x.x.x.x>
+
+  Set the address of the backend server that receives incoming traffic.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> server
+   <name> port <port>
+
+  Set the address of the backend port.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> server
+   <name> check
+
+  Active health check backend server.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> server
+   <name> check port <port>
+
+  Set an alternative port number for health checks.
+  Overrides the default server port used for TCP/HTTP checks.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> server
+   <name> send-proxy
+
+  Send a Proxy Protocol version 1 header (text format).
+
+.. cfgcmd:: set load-balancing haproxy backend <name> server
+   <name> send-proxy-v2
+
+  Send a Proxy Protocol version 2 header (binary format).
+
+.. cfgcmd:: set load-balancing haproxy backend <name> ssl
+   ca-certificate <ca-certificate>
+
+  Use SSL encryption for backend requests and authenticate the backend
+  against ``<ca-certificate>``.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> ssl no-verify
+
+  Use SSL encryption for backend requests without validating the server
+  certificate.
+
+.. cfgcmd:: set load-balancing haproxy backend <name>
+  http-response-headers <header-name> value <header-value>
+
+  Set custom HTTP headers to include in all responses from the backend.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> logging facility
+  <facility> level <level>
+
+  Specify facility and level for logging.
+  For an explanation on :ref:`syslog_facilities` and
+  :ref:`syslog_severity_level`,
+  see tables in the :ref:`syslog` configuration section.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> timeout check
+  <seconds>
+
+  Set the timeout in seconds for established connections.
+  Value range 1-3600 seconds.
+
+
+.. cfgcmd:: set load-balancing haproxy backend <name> timeout connect
+  <seconds>
+
+  Set the maximum time to wait for a connection attempt to a server to succeed.
+  Value range 1-3600 seconds.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> timeout server
+  <seconds>
+
+  Set the maximum inactivity time on the server side.
+  Value range 1-3600 seconds.
+
+
+
+Global
+-------
+
+Global configuration parameters:
+
+.. cfgcmd:: set load-balancing haproxy global-parameters max-connections
+   <num>
+
+  Limit maximum number of connections
+
+.. cfgcmd:: set load-balancing haproxy global-parameters ssl-bind-ciphers
+   <ciphers>
+
+  Limit the cipher algorithms allowed during SSL/TLS handshake.
+
+.. cfgcmd:: set load-balancing haproxy global-parameters tls-version-min
+   <version>
+
+  Specify the minimum required TLS version 1.2 or 1.3
+
+.. cfgcmd:: set load-balancing haproxy global-parameters logging
+  facility <facility> level <level>
+
+  Specify facility and level for logging.
+  For an explanation on :ref:`syslog_facilities` and
+  :ref:`syslog_severity_level`
+  see tables in syslog configuration section.
+
+.. cfgcmd:: set load-balancing haproxy timeout check <seconds>
+
+  Set the timeout in seconds for established connections.
+  Value range 1-3600 seconds. Default is 5 seconds.
+
+.. cfgcmd:: set load-balancing haproxy timeout client <seconds>
+
+  Set the maximum inactivity time on the client side.
+  Value range 1-3600 seconds. Default is 50 seconds.
+
+.. cfgcmd:: set load-balancing haproxy timeout connect <seconds>
+
+  Set the maximum time to wait for a connection attempt to a server to succeed.
+  Value range 1-3600 seconds. Default is 10 seconds.
+
+.. cfgcmd:: set load-balancing haproxy timeout server <seconds>
+
+  Set the maximum inactivity time on the server side.
+  Value range 1-3600 seconds. Default is 50 seconds.
+
+Health checks
+=============
+
+
+HTTP checks
+-----------
+
+Use HTTP health checks to monitor web applications that provide health status
+information and determine their availability.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> http-check
+
+  Enables HTTP health checks using OPTION HTTP requests against '/' and
+  expecting a successful response code in the 200-399 range.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> http-check
+   method <method>
+
+  Set the HTTP method: ``OPTION``, ``GET``, ``POST``, or ``PUT``.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> http-check
+   uri <path>
+
+  Set the endpoint to use for health checks.
+
+.. cfgcmd:: set load-balancing haproxy backend <name> http-check
+   expect <condition>
+
+  Set the expected result condition for a server to be considered healthy.
+
+  Some possible examples are:
+   * ``status 200`` Expecting a 200 response code
+   * ``status 200-399`` Expecting a non-failure response code
+   * ``string success`` Expecting the string `success` in the response body
+
+
+TCP checks
+----------
+
+Configure health checks for TCP mode backends. You can configure protocol-aware
+checks for a range of Layer 7 protocols:
+
+.. cfgcmd:: set load-balancing haproxy backend <name> health-check <protocol>
+
+  Available health check protocols:
+   * ``ldap`` LDAP protocol check.
+   * ``redis`` Redis protocol check.
+   * ``mysql`` MySQL protocol check.
+   * ``pgsql`` PostgreSQL protocol check.
+   * ``smtp`` SMTP protocol check.
+
+.. note:: If you specify a server to check but do not configure a
+   protocol, HAProxy performs a basic TCP health check. A server is online if
+   it responds to a connection attempt with a valid ``SYN/ACK`` packet.
+
+
+Redirect HTTP to HTTPS
+======================
+
+Configure a HAProxy service for HTTP that listens on port 80 and redirects
+incoming requests to HTTPS:
+
+.. code-block:: none
+
+    set load-balancing haproxy service http port '80'
+    set load-balancing haproxy service http redirect-http-to-https
+
+You can use a different service name; in this example, ``http`` is just for
+convenience.
+
+
+Examples
+========
+
+Level 4 balancing
+-----------------
+
+This configuration enables the TCP reverse proxy for the ``my-tcp-api``
+service. Incoming TCP connections on port 8888 are load balanced across the
+backend servers (srv01 and srv02) using the round-robin load balancing
+algorithm.
+
+.. code-block:: none
+
+    set load-balancing haproxy service my-tcp-api backend 'bk-01'
+    set load-balancing haproxy service my-tcp-api mode 'tcp'
+    set load-balancing haproxy service my-tcp-api port '8888'
+
+    set load-balancing haproxy backend bk-01 balance 'round-robin'
+    set load-balancing haproxy backend bk-01 mode 'tcp'
+
+    set load-balancing haproxy backend bk-01 server srv01 address '192.0.2.11'
+    set load-balancing haproxy backend bk-01 server srv01 port '8881'
+    set load-balancing haproxy backend bk-01 server srv02 address '192.0.2.12'
+    set load-balancing haproxy backend bk-01 server srv02 port '8882'
+
+
+Balancing based on domain name
+------------------------------
+The following configuration demonstrates how to use VyOS
+to achieve load balancing based on the domain name:
+
+The HTTP service listens on TCP port 80.
+
+Rule 10 matches requests with the domain name ``node1.example.com`` and
+forwards them to the backend ``bk-api-01``.
+
+Rule 20 matches requests with the domain name ``node2.example.com`` and
+forwards them to the backend ``bk-api-02``.
+
+.. code-block:: none
+
+    set load-balancing haproxy service http description 'bind app listen on 443 port'
+    set load-balancing haproxy service http mode 'tcp'
+    set load-balancing haproxy service http port '80'
+
+    set load-balancing haproxy service http rule 10 domain-name 'node1.example.com'
+    set load-balancing haproxy service http rule 10 set backend 'bk-api-01'
+    set load-balancing haproxy service http rule 20 domain-name 'node2.example.com'
+    set load-balancing haproxy service http rule 20 set backend 'bk-api-02'
+
+    set load-balancing haproxy backend bk-api-01 description 'My API-1'
+    set load-balancing haproxy backend bk-api-01 mode 'tcp'
+    set load-balancing haproxy backend bk-api-01 server api01 address '127.0.0.1'
+    set load-balancing haproxy backend bk-api-01 server api01 port '4431'
+    set load-balancing haproxy backend bk-api-02 description 'My API-2'
+    set load-balancing haproxy backend bk-api-02 mode 'tcp'
+    set load-balancing haproxy backend bk-api-02 server api01 address '127.0.0.2'
+    set load-balancing haproxy backend bk-api-02 server api01 port '4432'
+
+
+Terminate SSL
+-------------
+
+The following configuration terminates SSL on the router.
+
+The ``http`` service listens on port 80 and redirects HTTP requests to
+HTTPS.
+
+The ``https`` service listens on port 443 with the ``bk-default`` backend
+and handles HTTPS traffic using the ``cert`` certificate for SSL termination.
+The HSTS header is set with a 1-year expiry to tell browsers to always use
+SSL for the site.
+
+Rule 10 matches requests with the exact URL path ``/.well-known/xxx`` and
+redirects them to ``/certs/``.
+
+Rule 20 matches requests with URL paths ending in ``/mail`` or the exact
+path ``/email/bar`` and redirects them to ``/postfix/``.
+
+Global parameters include a maximum connection limit of 4000 and a minimum
+TLS version of 1.3.
+
+
+.. code-block:: none
+
+    set load-balancing haproxy service http description 'Force redirect to HTTPS'
+    set load-balancing haproxy service http port '80'
+    set load-balancing haproxy service http redirect-http-to-https
+
+    set load-balancing haproxy service https backend 'bk-default'
+    set load-balancing haproxy service https description 'listen on 443 port'
+    set load-balancing haproxy service https mode 'http'
+    set load-balancing haproxy service https port '443'
+    set load-balancing haproxy service https ssl certificate 'cert'
+    set load-balancing haproxy service https http-response-headers Strict-Transport-Security value 'max-age=31536000'
+
+    set load-balancing haproxy service https rule 10 url-path exact '/.well-known/xxx'
+    set load-balancing haproxy service https rule 10 set redirect-location '/certs/'
+    set load-balancing haproxy service https rule 20 url-path end '/mail'
+    set load-balancing haproxy service https rule 20 url-path exact '/email/bar'
+    set load-balancing haproxy service https rule 20 set redirect-location '/postfix/'
+
+    set load-balancing haproxy backend bk-default description 'Default backend'
+    set load-balancing haproxy backend bk-default mode 'http'
+    set load-balancing haproxy backend bk-default server sr01 address '192.0.2.23'
+    set load-balancing haproxy backend bk-default server sr01 port '80'
+
+    set load-balancing haproxy global-parameters max-connections '4000'
+    set load-balancing haproxy global-parameters tls-version-min '1.3'
+
+
+SSL Bridging
+-------------
+
+The following configuration terminates incoming HTTPS traffic on the router,
+then re-encrypts the traffic and sends it to the backend server via HTTPS.
+Use this when encryption is required for both paths but you do not want to
+install publicly trusted certificates on each backend server.
+
+Backend service certificates are checked against the certificate authority
+specified in the configuration, which could be an internal CA.
+
+The ``https`` service listens on port 443 with backend ``bk-bridge-ssl`` to
+handle HTTPS traffic. It uses certificate named ``cert`` for SSL termination.
+
+The ``bk-bridge-ssl`` backend connects to ``sr01`` server on port 443 via HTTPS
+and checks backend server has a valid certificate trusted by CA ``cacert``
+
+
+.. code-block:: none
+
+    set load-balancing haproxy service https backend 'bk-bridge-ssl'
+    set load-balancing haproxy service https description 'listen on 443 port'
+    set load-balancing haproxy service https mode 'http'
+    set load-balancing haproxy service https port '443'
+    set load-balancing haproxy service https ssl certificate 'cert'
+
+    set load-balancing haproxy backend bk-bridge-ssl description 'SSL backend'
+    set load-balancing haproxy backend bk-bridge-ssl mode 'http'
+    set load-balancing haproxy backend bk-bridge-ssl ssl ca-certificate 'cacert'
+    set load-balancing haproxy backend bk-bridge-ssl server sr01 address '192.0.2.23'
+    set load-balancing haproxy backend bk-bridge-ssl server sr01 port '443'
+
+
+Balancing with HTTP health checks
+---------------------------------
+
+This configuration enables HTTP health checks for backend servers.
+
+.. code-block:: none
+
+    set load-balancing haproxy service my-tcp-api backend 'bk-01'
+    set load-balancing haproxy service my-tcp-api mode 'tcp'
+    set load-balancing haproxy service my-tcp-api port '8888'
+
+    set load-balancing haproxy backend bk-01 balance 'round-robin'
+    set load-balancing haproxy backend bk-01 mode 'tcp'
+
+    set load-balancing haproxy backend bk-01 http-check method 'get'
+    set load-balancing haproxy backend bk-01 http-check uri '/health'
+    set load-balancing haproxy backend bk-01 http-check expect 'status 200'
+
+    set load-balancing haproxy backend bk-01 server srv01 address '192.0.2.11'
+    set load-balancing haproxy backend bk-01 server srv01 port '8881'
+    set load-balancing haproxy backend bk-01 server srv01 check
+    set load-balancing haproxy backend bk-01 server srv02 address '192.0.2.12'
+    set load-balancing haproxy backend bk-01 server srv02 port '8882'
+    set load-balancing haproxy backend bk-01 server srv02 check port '8892'
+