User authentication


Configure Kpow to read authentication and role information from a property file.

Use the exact configuration in this guide to restrict access to the following user/password/roles:

  • admin/admin/kafka-admins
  • jetty/jetty/kafka-users
  • other/other/kafka-admins+kafka-users
  • plain/plain/content-administrators
  • user/password/kafka-users

See: Jetty PropertyFileLoginModule guide for more detail or this guide to generating obfuscated passwords.


To enable PropertyFileLoginModule authentication:

  • Create a JAAS configuration file that tells the JVM what JAAS Module is in use.
  • Create a users property file containing information on users, passwords, and roles.
  • Set the AUTH_PROVIDER_TYPE=jetty environment variable.
  • Start the JAR or Docker container with

JAAS configuration

Create a JAAS PropertyFile configuration file (the kpow realm is very important).

kpow {
        org.eclipse.jetty.jaas.spi.PropertyFileLoginModule required

Create a users property file at the path configured in your JAAS config.

# This file defines users passwords and roles for a HashUserRealm
# The format is
#  <username>: <password>[,<rolename> ...]
# Passwords may be clear text, obfuscated or checksummed.  The class
# should be used to generate obfuscated
# passwords or password checksums
# If DIGEST Authentication is used, the password must be in a recoverable
# format, either plain text or OBF:.
# Credentials are jetty/jetty, admin/admin, other/other, plain/plain,
#                 user/password, and digest/digest
jetty: MD5:164c88b302622e17050af52c89945d44,kafka-users
admin: CRYPT:adpexzg3FUZAk,kafka-admins
other: OBF:1xmk1w261u9r1w1c1xmq,kafka-admins,kafka-users
plain: plain,content-administrators
user: password,kafka-users
# This entry is for digest auth.  The credential is a MD5 hash of
# username:realmname:password
digest: MD5:6e120743ad67abfbc385bc2bb754e297,kafka-users

Environment configuration

To activate Jetty JAAS authentication set the environment variable AUTH_PROVIDER_TYPE=jetty

JAR startup

Specify the JAAS config file by setting the following system property when starting the JAR:

Note: System properties must come after java but before -jar.

<... more env vars ...> \
java -jar /opt/kpow/latest.jar

Docker container startup

Note: The JVM provides an environment variable called JAVA_TOOL_OPTIONS that can be used in place of system properties. We use this to thread the JAAS config to Docker.

Set the env var

Note: When your JAAS config is on the host machine and not within the container you will need to configure a docker volume mount so that Kpow can read that configuration:

docker run --volume="/config/path:/config/path/" -p 3000:3000 --env-file ...

When starting the docker container you will see logging output similar to:


User experience

When configured your users will be prompted to authenticate on each new browser session.