Java21 container is minimal - yum does not work

[fitzget]

Hi
I am trying to build a docker container for a CICS test case we have. I am trying to create a container with Java 21. The Podman build command I am using uses the latest java21 container listed in the readme. My FROM: is pointing at full-java21-openj9-ubi-minimal

all the previous containers didn't have the -minimal suffix and our tests which build containers at Java 8, 11 & 17 did not fail

My docker file starts with

FROM icr.io/appcafe/websphere-liberty:full-java21-openj9-ubi-minimal
COPY server.xml /config
EXPOSE 9011
EXPOSE 9100
USER root

RUN yum check-update
&& yum install -y maven
&& yum install -y wget unzip
&& rm -rf /var/lib/apt/lists/*

and then fails on the RUN yum command with

STEP 6/97: RUN yum check-update && yum install -y maven && yum install -y wget unzip && rm -rf /var/lib/apt/lists/*
/bin/sh: line 1: yum: command not found

is there any reason the Java21 container is minimal and all previous ones are not

Many thanks
Tony Fitzgerald
CICS Development
IBM Hursley

[tjwatson]

is there any reason the Java21 container is minimal and all previous ones are not

The decision was to move Java 21 to minimal when we introduced the Java 21 images, but to keep the previous Java versions using the base UBI image so we do not break existing users of the other existing images.

For the UBI minimal images microdnf should be used instead of yum.

[fitzget]

Hi @tjwatson

thanks for that, microdnf has done the trick.

Many thanks for your help
Tony