Configuring Keycloak with Apache2

This post consists of the following parts:

  1. Downloading and configuring Keycloak (IdP)
  2. Downloading and configuring Apache2 to act as a reverse proxy in front of Keycloak (IdP)
  3. Bonus: Configuring Let’s encrypt (IdP)

IdP: identity provider in this post

Keycloak (IdP)

1. Download and configure Keycloak (Ubuntu 16.04)

1.1 Install Java

sudo apt install openjdk-8-jdk

1.2 Install Keycloak

mv /opt/keycloak/

Keycloak is now “installed” in /opt/keycloak/. Keycloak runs basically just on java scripts and no binaries are needed.

1.3 Add user for Keycloak

/opt/keycloak/bin/ -u username

1.4 Start the server

/opt/keycloak/bin/bin/ -b bind-address

Changing the bind-address to an IP address that is reachable from your configuration machine. Note that if you specify non-local address you cannot log in to the server without https. If you follow this tutorial further, set the bind address to

In the next step we configure HTTPS with Apache2 as a reverse proxy in front of Keycloak. If you don’t want to do that, please see for how to configure HTTPS in Keycloak.

1.5 Configure Keycloak for Apache (or any reverse proxy)

Set the following parameters in /opt/keycloak/standalone/configuration/standalone.xml

<subsystem xmlns="urn:jboss:domain:undertow:3.0">
  <server name="default-server">
    <!------- Change this line ----->
    <http-listener name="default" socket-binding="http" proxy-address-forwarding="true" redirect-socket="proxy-https" />
<socket-binding-group name="standard-sockets" default-interface=" ...
  <!------- Add this line ----->
  <socket-binding name="proxy-https" port="443"/>

1.6 Set up Keycloak as a service

Download the service scripts from:

Make sure to save both

  • keycloak-initd
  • keycloak-defaults

Place them in the following locations:

mv keycloak-defaults  /etc/default/keycloak
mv keycloak-initd      /etc/init.d/keycloak

Set the permissions and enable the new service

sudo chown root:root /etc/init.d/wildfly
sudo chmod +X /etc/init.d/keycloak
# Enable the new service
update-rc.d keycloak defaults
update-rc.d keycloak enable
# Create logging directory 
sudo mkdir -p /var/log/keycloak
# Create user to run keycloak as 
sudo useradd --system --shell /bin/false keycloak
# Set permissions for the new user
sudo chown -R keycloak /opt/keycloak/
sudo chown -R keycloak /var/log/keycloak/
# Finally, start the service
sudo service keycloak start

Keycloak should now be running

2. Configure apache (IdP)

2.1 Install apache2

sudo apt install apache2

2.2 Configure certificate for apache

Visit For instructions how to set up Let’s encrypt. They have a great tool and a guide so I won’t post it here. They make sure it’s relevant and updated for all environments.

2.3. Configure Apache to act as a reverse proxy

Put the following in /etc/apache2/sites-available/000-default-le-ssl.conf under <VirtualHost *:443>

    ProxyPreserveHost On
    SSLProxyEngine On
    SSLProxyCheckPeerCN on
    SSLProxyCheckPeerExpire on
    RequestHeader set X-Forwarded-Proto "https"
    RequestHeader set X-Forwarded-Port "443"
    ProxyPass /
    ProxyPassReverse /

If you want to disable admin console from the world, you can set the ProxyPass parameter as follows:

    ProxyPass /auth/realms/

You can still access the admin console from on the server

Author | Markus Lehtonen

Currently undergraduate student at Aalto University. Interested in all things infosec.