Enable Filebeat's Journald input in some docker image variants

changelog/fragments/1745609163-journalctl-on-all-docker-variants.yaml

@@ -0,0 +1,33 @@
+# Kind can be one of:
+# - breaking-change: a change to previously-documented behavior
+# - deprecation: functionality that is being removed in a later release
+# - bug-fix: fixes a problem in a previous version
+# - enhancement: extends functionality but does not break or fix existing behavior
+# - feature: new functionality
+# - known-issue: problems that we are aware of in a given version
+# - security: impacts on the security of a product or a user’s deployment.
+# - upgrade: important information for someone upgrading from a prior version
+# - other: does not fit into any of the other categories
+kind: bug-fix
+
+# Change summary; a 80ish characters long description of the change.
+summary: Ship journalctl on all Docker image variants
+
+# Long description; in case the summary is not enough to describe the change
+# this field accommodate a description without length limits.
+# NOTE: This field will be rendered only for breaking-change and known-issue kinds at the moment.
+description: |
+  Filebeat's Journald input requires journalctl, so the systemd package is added to all docker image variants.
+
+# Affected component; usually one of "elastic-agent", "fleet-server", "filebeat", "metricbeat", "auditbeat", "all", etc.
+component: elastic-agent
+
+# PR URL; optional; the PR number that added the changeset.
+# If not present is automatically filled by the tooling finding the PR where this changelog fragment has been added.
+# NOTE: the tooling supports backports, so it's able to fill the original PR number instead of the backport PR number.
+# Please provide it if you are adding a fragment for a different PR.
+pr: https://github.com/elastic/elastic-agent/pull/7995
+
+# Issue URL; optional; the GitHub issue related to this changeset (either closes or is part of).
+# If not present is automatically filled by the tooling with the issue linked to the PR number.
+issue: https://github.com/elastic/beats/issues/44040

dev-tools/packaging/templates/docker/Dockerfile.elastic-agent.tmpl

@@ -73,15 +73,15 @@ ENV BEAT_SETUID_AS={{ .user }}
 {{- if contains .from "ubi-minimal" }}
 RUN for iter in {1..10}; do \
         microdnf update -y && \
-        microdnf install -y tar gzip findutils shadow-utils ca-certificates gawk libcap xz && \
+        microdnf install -y tar gzip findutils shadow-utils ca-certificates gawk libcap xz systemd && \
         microdnf clean all && \
         exit_code=0 && break || exit_code=$? && echo "microdnf error: retry $iter in 10s" && sleep 10; done; (exit $exit_code)
 {{- end }}
 
 {{- if contains .from "wolfi" }}
 RUN for iter in {1..10}; do \
         apk fix && \
-        apk add --no-cache ca-certificates curl gawk shadow bash && \
+        apk add --no-cache ca-certificates curl gawk shadow bash systemd && \
         exit_code=0 && break || exit_code=$? && echo "apk error: retry $iter in 10s" && sleep 10; \
     done; \
     (exit $exit_code)