Enables which HTTP codes should be passed for processing with the [error_page directive](http://nginx.org/en/docs/http/ngx_http_core_module.html#error_page).
Setting at least one code also enables [proxy_intercept_errors](http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_intercept_errors) which are required to process error_page.
HTTP Strict Transport Security (often abbreviated as HSTS) is a security feature (HTTP header) that tell browsers that it should only be communicated with using HTTPS, instead of using HTTP. It provides protection against protocol downgrade attacks and cookie theft.
Sets the maximum number of simultaneous connections that can be opened by each [worker process](http://nginx.org/en/docs/ngx_core_module.html#worker_connections)
Sets the size of the buffer used for [reading the first part of the response](http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_buffer_size) received from the proxied server. This part usually contains a small response header.
Sets the timeout for [establishing a connection with a proxied server](http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_connect_timeout). It should be noted that this timeout cannot usually exceed 75 seconds.
Sets a text that [should be changed in the domain attribute](http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_cookie_domain) of the “Set-Cookie” header fields of a proxied server response.
Sets a text that [should be changed in the path attribute](http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_cookie_path) of the “Set-Cookie” header fields of a proxied server response.
Sets the timeout in seconds for [reading a response from the proxied server](http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_read_timeout). The timeout is set only between two successive read operations, not for the transmission of the whole response.
#### proxy-send-timeout
Sets the timeout in seconds for [transmitting a request to the proxied server](http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_send_timeout). The timeout is set only between two successive write operations, not for the transmission of the whole request.
#### proxy-next-upstream
Specifies in [which cases](http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_next_upstream) a request should be passed to the next server.
#### proxy-request-buffering
Enables or disables [buffering of a client request body](http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_request_buffering).
#### retry-non-idempotent
Since 1.9.13 NGINX will not retry non-idempotent requests (POST, LOCK, PATCH) in case of an error in the upstream server.
Sets the maximum size of the [server names hash tables](http://nginx.org/en/docs/http/ngx_http_core_module.html#server_names_hash_max_size) used in server names,map directive’s values, MIME types, names of request header strings, etc.
The ordering of a ciphersuite is very important because it decides which algorithms are going to be selected in priority.
The recommendation above prioritizes algorithms that provide perfect [forward secrecy](https://wiki.mozilla.org/Security/Server_Side_TLS#Forward_Secrecy).
Please check the [Mozilla SSL Configuration Generator](https://mozilla.github.io/server-side-tls/ssl-config-generator/).
Enables or disables the use of shared [SSL cache](http://nginx.org/en/docs/http/ngx_http_ssl_module.html#ssl_session_cache) among worker processes.
#### ssl-session-cache-size
Sets the size of the [SSL shared session cache](http://nginx.org/en/docs/http/ngx_http_ssl_module.html#ssl_session_cache) between all worker processes.
Sets the time during which a client may [reuse the session](http://nginx.org/en/docs/http/ngx_http_ssl_module.html#ssl_session_timeout) parameters stored in a cache.
#### upstream-max-fails
Sets the number of unsuccessful attempts to communicate with the [server](http://nginx.org/en/docs/http/ngx_http_upstream_module.html#upstream) that should happen in the duration set by the `fail_timeout` parameter to consider the server unavailable.
Sets the time during which the specified number of unsuccessful attempts to communicate with the [server](http://nginx.org/en/docs/http/ngx_http_upstream_module.html#upstream) should happen to consider the server unavailable.
The default mime type list to compress is: `application/atom+xml application/javascript aplication/x-javascript application/json application/rss+xml application/vnd.ms-fontobject application/x-font-ttf application/x-web-app-manifest+json application/xhtml+xml application/xml font/opentype image/svg+xml image/x-icon text/css text/plain text/x-component`.
Enables or disables [HTTP/2](http://nginx.org/en/docs/http/ngx_http_v2_module.html) support in secure connections.
#### use-proxy-protocol
Enables or disables the [PROXY protocol](https://www.nginx.com/resources/admin-guide/proxy-protocol/) to receive client connection (real IP address) information passed through proxy servers and load balancers such as HAProxy and Amazon Elastic Load Balancer (ELB).
#### whitelist-source-range
Sets the default whitelisted IPs for each `server` block.
This can be overwritten by an annotation on an Ingress rule.
See [ngx_http_access_module](http://nginx.org/en/docs/http/ngx_http_access_module.html).
Sets parameters for a shared memory zone that will keep states for various keys of [limit_conn_zone](http://nginx.org/en/docs/http/ngx_http_limit_conn_module.html#limit_conn_zone). The default of "$binary_remote_addr" variable’s size is always 4 bytes for IPv4 addresses or 16 bytes for IPv6 addresses.
Sets custom headers from a configmap before sending traffic to backends. See [example](https://github.com/kubernetes/ingress-nginx/tree/master/deploy/examples/customization/custom-headers)
Sets custom headers from a configmap before sending traffic to the client. See `proxy-set-headers` [example](https://github.com/kubernetes/ingress-nginx/tree/master/docs/examples/customization/custom-headers)
