How to get kerberos to work with the quay.io/keycloak/keycloak:26.2.5

Configuring the server
1

I am using the official Keycloak podman container.

I have configured the kerberos authentication, but get the “checksum error” message, indicating that the java does not understand the provided kerberos encryption.

When we dug into this; it seams to be that kerberos libraries is not included in the image built and provided by keycloak?

I tried to install krb5-libs but as neither “dnf” or “yum” works (it is a hardened image); how to install the needed libraries to make “kerberos” to work.

Regards Tomas

2

You need to build your own image,

FROM quay.io/keycloak/keycloak:26.4.2 as builder

FROM  alpine:latest
RUN apk add ....

COPY --from=builder --chown=1000:0 /opt/keycloak /opt/keycloak
RUN /opt/keycloak/bin/kc.sh build --metrics-enabled=true --health-enabled=true

USER 1000

EXPOSE 8080
EXPOSE 8443
EXPOSE 9000


ENV ....

CMD [‘start’,‘–optimized’]
ENTRYPOINT [ “/opt/keycloak/bin/kc.sh” ]