# Using a reverse proxy with Synapse It is recommended to put a reverse proxy such as [nginx](https://nginx.org/en/docs/http/ngx_http_proxy_module.html), [Apache](https://httpd.apache.org/docs/current/mod/mod_proxy_http.html), [Caddy](https://caddyserver.com/docs/quick-starts/reverse-proxy), [HAProxy](https://www.haproxy.org/) or [relayd](https://man.openbsd.org/relayd.8) in front of Synapse. One advantage of doing so is that it means that you can expose the default https port (443) to Matrix clients without needing to run Synapse with root privileges. You should configure your reverse proxy to forward requests to `/_matrix` or `/_synapse/client` to Synapse, and have it set the `X-Forwarded-For` and `X-Forwarded-Proto` request headers. You should remember that Matrix clients and other Matrix servers do not necessarily need to connect to your server via the same server name or port. Indeed, clients will use port 443 by default, whereas servers default to port 8448. Where these are different, we refer to the 'client port' and the 'federation port'. See [the Matrix specification](https://matrix.org/docs/spec/server_server/latest#resolving-server-names) for more details of the algorithm used for federation connections, and [Delegation](delegate.md) for instructions on setting up delegation. **NOTE**: Your reverse proxy must not `canonicalise` or `normalise` the requested URI in any way (for example, by decoding `%xx` escapes). Beware that Apache *will* canonicalise URIs unless you specify `nocanon`. Let's assume that we expect clients to connect to our server at `https://matrix.example.com`, and other servers to connect at `https://example.com:8448`. The following sections detail the configuration of the reverse proxy and the homeserver. ## Homeserver Configuration The HTTP configuration will need to be updated for Synapse to correctly record client IP addresses and generate redirect URLs while behind a reverse proxy. In `homeserver.yaml` set `x_forwarded: true` in the port 8008 section and consider setting `bind_addresses: ['127.0.0.1']` so that the server only listens to traffic on localhost. (Do not change `bind_addresses` to `127.0.0.1` when using a containerized Synapse, as that will prevent it from responding to proxied traffic.) Optionally, you can also set [`request_id_header`](./usage/configuration/config_documentation.md#listeners) so that the server extracts and re-uses the same request ID format that the reverse proxy is using. ## Reverse-proxy configuration examples **NOTE**: You only need one of these. ### nginx ```nginx server { listen 443 ssl; listen [::]:443 ssl; # For the federation port listen 8448 ssl default_server; listen [::]:8448 ssl default_server; server_name matrix.example.com; location ~ ^(/_matrix|/_synapse/client) { # note: do not add a path (even a single /) after the port in `proxy_pass`, # otherwise nginx will canonicalise the URI and cause signature verification # errors. proxy_pass http://localhost:8008; proxy_set_header X-Forwarded-For $remote_addr; proxy_set_header X-Forwarded-Proto $scheme; proxy_set_header Host $host; # Nginx by default only allows file uploads up to 1M in size # Increase client_max_body_size to match max_upload_size defined in homeserver.yaml client_max_body_size 50M; # Synapse responses may be chunked, which is an HTTP/1.1 feature. proxy_http_version 1.1; } } ``` ### Caddy v2 ``` matrix.example.com { reverse_proxy /_matrix/* localhost:8008 reverse_proxy /_synapse/client/* localhost:8008 } example.com:8448 { reverse_proxy /_matrix/* localhost:8008 } ``` [Delegation](delegate.md) example: ``` example.com { header /.well-known/matrix/* Content-Type application/json header /.well-known/matrix/* Access-Control-Allow-Origin * respond /.well-known/matrix/server `{"m.server": "matrix.example.com:443"}` respond /.well-known/matrix/client `{"m.homeserver":{"base_url":"https://matrix.example.com"},"m.identity_server":{"base_url":"https://identity.example.com"}}` } matrix.example.com { reverse_proxy /_matrix/* localhost:8008 reverse_proxy /_synapse/client/* localhost:8008 } ``` ### Apache ```apache <VirtualHost *:443> SSLEngine on ServerName matrix.example.com RequestHeader set "X-Forwarded-Proto" expr=%{REQUEST_SCHEME} AllowEncodedSlashes NoDecode ProxyPreserveHost on ProxyPass /_matrix http://127.0.0.1:8008/_matrix nocanon ProxyPassReverse /_matrix http://127.0.0.1:8008/_matrix ProxyPass /_synapse/client http://127.0.0.1:8008/_synapse/client nocanon ProxyPassReverse /_synapse/client http://127.0.0.1:8008/_synapse/client </VirtualHost> <VirtualHost *:8448> SSLEngine on ServerName example.com RequestHeader set "X-Forwarded-Proto" expr=%{REQUEST_SCHEME} AllowEncodedSlashes NoDecode ProxyPass /_matrix http://127.0.0.1:8008/_matrix nocanon ProxyPassReverse /_matrix http://127.0.0.1:8008/_matrix </VirtualHost> ``` **NOTE**: ensure the `nocanon` options are included. **NOTE 2**: It appears that Synapse is currently incompatible with the ModSecurity module for Apache (`mod_security2`). If you need it enabled for other services on your web server, you can disable it for Synapse's two VirtualHosts by including the following lines before each of the two `</VirtualHost>` above: ```apache <IfModule security2_module> SecRuleEngine off </IfModule> ``` **NOTE 3**: Missing `ProxyPreserveHost on` can lead to a redirect loop. ### HAProxy ``` frontend https bind *:443,[::]:443 ssl crt /etc/ssl/haproxy/ strict-sni alpn h2,http/1.1 http-request set-header X-Forwarded-Proto https if { ssl_fc } http-request set-header X-Forwarded-Proto http if !{ ssl_fc } http-request set-header X-Forwarded-For %[src] # Matrix client traffic acl matrix-host hdr(host) -i matrix.example.com matrix.example.com:443 acl matrix-path path_beg /_matrix acl matrix-path path_beg /_synapse/client use_backend matrix if matrix-host matrix-path frontend matrix-federation bind *:8448,[::]:8448 ssl crt /etc/ssl/haproxy/synapse.pem alpn h2,http/1.1 http-request set-header X-Forwarded-Proto https if { ssl_fc } http-request set-header X-Forwarded-Proto http if !{ ssl_fc } http-request set-header X-Forwarded-For %[src] default_backend matrix backend matrix server matrix 127.0.0.1:8008 ``` Example configuration, if using a UNIX socket. The configuration lines regarding the frontends do not need to be modified. ``` backend matrix server matrix unix@/run/synapse/main_public.sock ``` Example configuration when using a single port for both client and federation traffic. ``` frontend https bind *:443,[::]:443 ssl crt /etc/ssl/haproxy/ strict-sni alpn h2,http/1.1 http-request set-header X-Forwarded-Proto https if { ssl_fc } http-request set-header X-Forwarded-Proto http if !{ ssl_fc } http-request set-header X-Forwarded-For %[src] acl matrix-host hdr(host) -i matrix.example.com matrix.example.com:443 acl matrix-sni ssl_fc_sni matrix.example.com acl matrix-path path_beg /_matrix acl matrix-path path_beg /_synapse/client use_backend matrix if matrix-host matrix-path use_backend matrix if matrix-sni backend matrix server matrix 127.0.0.1:8008 ``` [Delegation](delegate.md) example: ``` frontend https acl matrix-well-known-client-path path /.well-known/matrix/client acl matrix-well-known-server-path path /.well-known/matrix/server use_backend matrix-well-known-client if matrix-well-known-client-path use_backend matrix-well-known-server if matrix-well-known-server-path backend matrix-well-known-client http-after-response set-header Access-Control-Allow-Origin "*" http-after-response set-header Access-Control-Allow-Methods "GET, POST, PUT, DELETE, OPTIONS" http-after-response set-header Access-Control-Allow-Headers "Origin, X-Requested-With, Content-Type, Accept, Authorization" http-request return status 200 content-type application/json string '{"m.homeserver":{"base_url":"https://matrix.example.com"},"m.identity_server":{"base_url":"https://identity.example.com"}}' backend matrix-well-known-server http-after-response set-header Access-Control-Allow-Origin "*" http-after-response set-header Access-Control-Allow-Methods "GET, POST, PUT, DELETE, OPTIONS" http-after-response set-header Access-Control-Allow-Headers "Origin, X-Requested-With, Content-Type, Accept, Authorization" http-request return status 200 content-type application/json string '{"m.server":"matrix.example.com:443"}' ``` ### Relayd ``` table <webserver> { 127.0.0.1 } table <matrixserver> { 127.0.0.1 } http protocol "https" { tls { no tlsv1.0, ciphers "HIGH" } tls keypair "example.com" match header set "X-Forwarded-For" value "$REMOTE_ADDR" match header set "X-Forwarded-Proto" value "https" # set CORS header for .well-known/matrix/server, .well-known/matrix/client # httpd does not support setting headers, so do it here match request path "/.well-known/matrix/*" tag "matrix-cors" match response tagged "matrix-cors" header set "Access-Control-Allow-Origin" value "*" pass quick path "/_matrix/*" forward to <matrixserver> pass quick path "/_synapse/client/*" forward to <matrixserver> # pass on non-matrix traffic to webserver pass forward to <webserver> } relay "https_traffic" { listen on egress port 443 tls protocol "https" forward to <matrixserver> port 8008 check tcp forward to <webserver> port 8080 check tcp } http protocol "matrix" { tls { no tlsv1.0, ciphers "HIGH" } tls keypair "example.com" block pass quick path "/_matrix/*" forward to <matrixserver> pass quick path "/_synapse/client/*" forward to <matrixserver> } relay "matrix_federation" { listen on egress port 8448 tls protocol "matrix" forward to <matrixserver> port 8008 check tcp } ``` ## Health check endpoint Synapse exposes a health check endpoint for use by reverse proxies. Each configured HTTP listener has a `/health` endpoint which always returns 200 OK (and doesn't get logged). ## Synapse administration endpoints Endpoints for administering your Synapse instance are placed under `/_synapse/admin`. These require authentication through an access token of an admin user. However as access to these endpoints grants the caller a lot of power, we do not recommend exposing them to the public internet without good reason.