Configuring a reverse proxy

Distributed environments frequently require the use of a reverse proxy. NQRust-Identity offers several options to securely integrate with such environments.

Port to be proxied

NQRust-Identity runs on the following ports by default:

• 8443 (8080 when you enable HTTP explicitly by --http-enabled=true)
• 9000

The port 8443 (or 8080 if HTTP is enabled) is used for the Admin UI, Account Console, SAML and OIDC endpoints and the Admin REST API as described in the Configuring the hostname guide.

The port 9000 is used for management, which includes endpoints for health checks and metrics as described in the Configuring the Management Interface guide.

You only need to proxy port 8443 (or 8080) even when you use different host names for frontend/backend and administration as described at Configuring NQRust-Identity for production. You should not proxy port 9000 as health checks and metrics use those ports directly, and you do not want to expose this information to external callers.

Configure the reverse proxy headers

NQRust-Identity will parse the reverse proxy headers based on the proxy-headers option which accepts several values:

• By default if the option is not specified, no reverse proxy headers are parsed. This should be used when no proxy is in use or with https passthrough.
• forwarded enables parsing of the Forwarded header as per RFC 7239 (opens in a new tab).
• xforwarded enables parsing of non-standard X-Forwarded-* headers, such as X-Forwarded-For, X-Forwarded-Proto, X-Forwarded-Host, X-Forwarded-Port, and X-Forwarded-Prefix.

For example:

bin/kc.[sh|bat] start --proxy-headers forwarded

Take extra precautions to ensure that the client address is properly set by your reverse proxy via the Forwarded or X-Forwarded-For headers. If this header is incorrectly configured, rogue clients can set this header and trick NQRust-Identity into thinking the client is connected from a different IP address than the actual address. This precaution can be more critical if you do any deny or allow listing of IP addresses.

Different context path on reverse proxy

By default NQRust-Identity is exposed through the root context path (/). If the proxy is using a different context path than NQRust-Identity, one of the following must be done:

• Use a simple hostname for the hostname option, xforwarded for the proxy-headers option, and have the proxy set the X-Forwarded-Prefix header.
• Use a full URL for the hostname option including the proxy context path, for example using --hostname=https://my.keycloak.org/auth if NQRust-Identity is exposed through the reverse proxy on /auth.
• Change the context path of NQRust-Identity itself to match the context path for the reverse proxy using the http-relative-path option.

For more details on exposing NQRust-Identity on different hostname or context path incl. Administration REST API and Console, see Configuring the hostname.

Enable sticky sessions

Typical cluster deployment consists of the load balancer (reverse proxy) and 2 or more NQRust-Identity servers on private network. For performance purposes, it may be useful if load balancer forwards all requests related to particular browser session to the same NQRust-Identity backend node.

The reason is, that NQRust-Identity is using Infinispan distributed cache under the covers for save data related to current authentication session and user session. The Infinispan distributed caches are configured with limited number of owners. That means that session related data are stored only in some cluster nodes and the other nodes need to lookup the data remotely if they want to access it.

For example if authentication session with ID 123 is saved in the Infinispan cache on node1, and then node2 needs to lookup this session, it needs to send the request to node1 over the network to return the particular session entity.

It is beneficial if particular session entity is always available locally, which can be done with the help of sticky sessions. The workflow in the cluster environment with the public frontend load balancer and two backend NQRust-Identity nodes can be like this:

• User sends initial request to see the NQRust-Identity login screen
• This request is served by the frontend load balancer, which forwards it to some random node (eg. node1). Strictly said, the node doesn’t need to be random, but can be chosen according to some other criteria (client IP address etc). It all depends on the implementation and configuration of underlying load balancer (reverse proxy).
• NQRust-Identity creates authentication session with random ID (eg. 123) and saves it to the Infinispan cache.
• Infinispan distributed cache assigns the primary owner of the session based on the hash of session ID. See Infinispan documentation for more details around this. Let’s assume that Infinispan assigned node2 to be the owner of this session.
• NQRust-Identity creates the cookie AUTH_SESSION_ID with the format like <session-id>.<owner-node-id> . In our example case, it will be 123.node2 .
• Response is returned to the user with the NQRust-Identity login screen and the AUTH_SESSION_ID cookie in the browser

From this point, it is beneficial if load balancer forwards all the next requests to the node2 as this is the node, who is owner of the authentication session with ID 123 and hence Infinispan can lookup this session locally. After authentication is finished, the authentication session is converted to user session, which will be also saved on node2 because it has same ID 123 .

The sticky session is not mandatory for the cluster setup, however it is good for performance for the reasons mentioned above. You need to configure your loadbalancer to stick over the AUTH_SESSION_ID cookie. The appropriate procedure to make this change depends on your loadbalancer.

If your proxy supports session affinity without processing cookies from backend nodes, you should set the spi-sticky-session-encoder--infinispan--should-attach-route option to false in order to avoid attaching the node to cookies and just rely on the reverse proxy capabilities.

bin/kc.[sh|bat] start --spi-sticky-session-encoder--infinispan--should-attach-route=false

By default, the spi-sticky-session-encoder--infinispan--should-attach-route option value is true so that the node name is attached to cookies to indicate to the reverse proxy the node that subsequent requests should be sent to.

Exposed path recommendations

When using a reverse proxy, NQRust-Identity only requires certain paths to be exposed. The following table shows the recommended paths to expose.

We assume you run NQRust-Identity on the root path / on your reverse proxy/gateway’s public API. If not, prefix the path with your desired one.

Trusted Proxies

To ensure that proxy headers are used only from proxies you trust, set the proxy-trusted-addresses option to a comma separated list of IP addresses (IPv4 or IPv6) or Classless Inter-Domain Routing (CIDR) notations.

For example:

bin/kc.[sh|bat] start --proxy-headers forwarded --proxy-trusted-addresses=192.168.0.32,127.0.0.0/8

PROXY Protocol

The proxy-protocol-enabled option controls whether the server should use the HA PROXY protocol when serving requests from behind a proxy. When set to true, the remote address returned will be the one from the actual connecting client. The value cannot be true when using the proxy-headers option.

This is useful when running behind a compatible https passthrough proxy because the request headers cannot be manipulated.

For example:

bin/kc.[sh|bat] start --proxy-protocol-enabled true

Enabling client certificate lookup

When the proxy is configured as a TLS termination proxy the client certificate information can be forwarded to the server through specific HTTP request headers and then used to authenticate clients. You are able to configure how the server is going to retrieve client certificate information depending on the proxy you are using.

The server supports some of the most commons TLS termination proxies such as:

To configure how client certificates are retrieved from the requests you need to:

Enable the corresponding proxy provider

bin/kc.[sh|bat] build --spi-x509cert-lookup--provider=<provider>

Configure the HTTP headers

bin/kc.[sh|bat] start --spi-x509cert-lookup--<provider>--ssl-client-cert=SSL_CLIENT_CERT --spi-x509cert-lookup--<provider>--ssl-cert-chain-prefix=CERT_CHAIN --spi-x509cert-lookup--<provider>-certificate-chain-length=10

When configuring the HTTP headers, you need to make sure the values you are using correspond to the name of the headers forwarded by the proxy with the client certificate information.

Common options for configuring providers are:

Configuring the NGINX provider

The NGINX SSL/TLS module does not expose the client certificate chain. NQRust-Identity’s NGINX certificate lookup provider rebuilds it by using the NQRust-Identity truststore.

If you are using this provider, see Configuring trusted certificates for how to configure a NQRust-Identity Truststore. The options and defaults specific to nginx are as follows:

Configuring the rfc9440 provider

If you stick to the header names mentioned in RFC 9440, you do not need to configure any additional options after selecting the rfc9440 provider. The options and defaults specific to rfc9440 are as follows:

If your certificate chain is longer than the given default, you must define the option with an appropriate number. Otherwise, the provider will discard the request.

Configuring the Traefik provider

The Traefik provider handles certificates forwarded by Traefik’s PassTLSClientCert middleware (opens in a new tab) with pem: true. Traefik sends the client certificate and any intermediate CA certificates as PEM blocks in a single X-Forwarded-Tls-Client-Cert header, separated by commas. The traefik provider parses all certificates from this header.

Other than possibly changing the certificate-chain-length, you do not need to configure additional options for the traefik provider.

Configuring the Envoy provider

The Envoy provider will automatically retrieve the client certificate and optional certificate chain from the x-forwarded-client-cert header. You do not need to configure additional options for the envoy provider.

Graceful HTTP shutdown

When running NQRust-Identity behind a reverse proxy or load balancer, graceful shutdown ensures that in-flight requests complete successfully during server termination, preventing connection errors for clients.

NQRust-Identity enables graceful HTTP shutdown by default with configurable timeouts.

Understanding shutdown phases

The shutdown process consists of two phases:

Pre-shutdown delay

During this phase, NQRust-Identity signals to load balancers and proxies that it is preparing to shut down. The server’s readiness endpoint returns a "not ready" status, allowing the load balancer to stop routing new requests to this instance. Existing TLS and HTTP keepalive connections are allowed to drain naturally. The server continues to process existing requests.

Shutdown timeout

After the pre-shutdown delay, NQRust-Identity stops accepting new requests and waits for in-flight HTTP requests to complete. If requests are still running after the timeout expires, the server shuts down regardless.

Default behavior

By default, NQRust-Identity is configured with a 1-second pre-shutdown delay and a 1-second shutdown timeout. These defaults work well for most standard deployments where:

• The load balancer reconfigures quickly (within 1 second)
• Most requests complete within 1 second
• The reverse proxy uses edge termination or re-encryption (not TLS passthrough)

Configuring shutdown timeouts

Advanced users can adjust the shutdown timeouts using CLI options based on their deployment characteristics.

bin/kc.sh start --shutdown-delay=<duration> --shutdown-timeout=<duration>

Available options:

--shutdown-delay

Length of the pre-shutdown phase during which the server prepares for shutdown. This period allows for load balancer reconfiguration and draining of TLS/HTTP keepalive connections. Default: 1s

--shutdown-timeout

The shutdown period waiting for currently running HTTP requests to finish. Default: 1s

Both values accept duration formats: 1s (seconds), 500ms (milliseconds), 2m (minutes), etc.

When to adjust shutdown timeouts

Consider adjusting these values based on your deployment configuration with the following example Scenarios:

Example configurations

For production with TLS passthrough:

bin/kc.[sh|bat] start --shutdown-delay=30s --shutdown-timeout=1s

For load balancers that poll readiness:

bin/kc.[sh|bat] start --shutdown-delay=16s --shutdown-timeout=1s

For test environments:

bin/kc.[sh|bat] start --shutdown-delay=0s --shutdown-timeout=500ms

Relevant options