[8.18] Update docker default base to Ubuntu 24.04 (#128732)

* [8.18] Update docker default base to Ubuntu 24.04

* Update docs/changelog/128732.yaml

* Tweak changelog

Author: breskeby

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/DockerBase.java

@@ -13,7 +13,7 @@
  * This class models the different Docker base images that are used to build Docker distributions of Elasticsearch.
  */
 public enum DockerBase {
-    DEFAULT("ubuntu:20.04", "", "apt-get"),
+    DEFAULT("ubuntu:24.04", "", "apt-get"),
 
     // "latest" here is intentional, since the image name specifies "8"
     UBI("docker.elastic.co/ubi8/ubi-minimal:latest", "-ubi8", "microdnf"),

distribution/docker/src/docker/Dockerfile

@@ -183,7 +183,7 @@ RUN yes no | dpkg-reconfigure dash && \\
       "      ${package_manager} update && \n" +
       "      ${package_manager} upgrade -y && \n" +
       "      ${package_manager} install -y --no-install-recommends \n" +
-      "        ca-certificates curl netcat p11-kit unzip zip ${docker_base == 'cloud' ? 'wget' : '' } && \n" +
+      "        ca-certificates curl netcat-openbsd p11-kit unzip zip ${docker_base == 'cloud' ? 'wget' : '' } && \n" +
       "      ${package_manager} clean && \n" +
       "      rm -rf /var/lib/apt/lists/*"
   ) %>
@@ -202,9 +202,10 @@ RUN <%= retry.loop(
 
 
 <% if (docker_base == "default" || docker_base == "cloud") { %>
-RUN groupadd -g 1000 elasticsearch && \\
-    adduser --uid 1000 --gid 1000 --home /usr/share/elasticsearch elasticsearch && \\
-    adduser elasticsearch root && \\
+RUN userdel -r ubuntu && \\
+    groupadd -g 1000 elasticsearch && \\
+    useradd --uid 1000 --gid 1000 --home-dir /usr/share/elasticsearch --create-home elasticsearch && \\
+    usermod -aG root elasticsearch && \\
     chown -R 0:0 /usr/share/elasticsearch
 <% } else if (docker_base == "wolfi") { %>
 RUN groupadd -g 1000 elasticsearch && \

docs/changelog/128732.yaml

@@ -0,0 +1,5 @@
+pr: 128732
+summary: "Update default docker base image to Ubuntu 24.04"
+area: Packaging
+type: upgrade
+issues: []