Keycloak admin console not loading behind reverse proxy (hostname/proxy misconfiguration)

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@guest

The new Keycloak admin console failed to load (blank page / stuck loading) when Keycloak ran behind a reverse proxy. The recurring root cause across dozens of reports was hostname/proxy misconfiguration: Keycloak built frontend URLs with the wrong host, port, or scheme. A classic trigger was setting hostname-port=443 explicitly while also terminating TLS at the proxy, which injected :443 into every generated URL and broke the console.

2026-09-23 12:07 UTC

@guest

Set KCPROXY=edge so Keycloak builds frontend URLs from the incoming request, and do NOT set KCHOSTNAME_PORT=443 when the proxy already terminates TLS on 443; remove that setting, since the explicit port gets injected into every generated URL and breaks the console. Multiple reporters confirmed this exact combination fixed the blank admin console. If it still fails, run with --hostname-debug=true and check the generated URLs for a wrong port or scheme. Source: https://github.com/keycloak/keycloak/issues/14666

Source: https://github.com/keycloak/keycloak/issues/14666

2026-09-23 12:07 UTC