feat: add openssh for mpi-operator v2

ompp-run-ubuntu/Dockerfile

@@ -52,6 +52,7 @@ RUN echo "ulimit -S -s 65536" >> etc/bash.bashrc && \
     apt-get upgrade -y && \
     rm -rf /var/lib/apt/lists/*
 
+# Install kubectl cli to be able to utilize file transfer functionality between containers
 ARG KUBECTL_VERSION=v1.28.2
 ARG KUBECTL_URL=https://dl.k8s.io/release/${KUBECTL_VERSION}/bin/linux/amd64/kubectl
 ARG KUBECTL_SHA=c922440b043e5de1afa3c1382f8c663a25f055978cbc6e8423493ec157579ec5
@@ -65,6 +66,19 @@ RUN curl -LO "${KUBECTL_URL}" \
 RUN rm -f /etc/localtime && \
     ln -s /usr/share/zoneinfo/America/Toronto /etc/localtime
 
+# Install OpenSSH for MPI to communicate between containers
+RUN apt-get install -y --no-install-recommends openssh-client openssh-server && \
+    mkdir -p /var/run/sshd
+
+# Allow OpenSSH to talk to containers without asking for confirmation
+# by disabling StrictHostKeyChecking.
+# mpi-operator mounts the .ssh folder from a Secret. For that to work, we need
+# to disable UserKnownHostsFile to avoid write permissions.
+# Disabling StrictModes avoids directory and files read permission checks.
+RUN sed -i 's/[ #]\(.*StrictHostKeyChecking \).*/ \1no/g' /etc/ssh/ssh_config && \
+    echo "    UserKnownHostsFile /dev/null" >> /etc/ssh/ssh_config && \
+    sed -i 's/#\(StrictModes \).*/\1no/g' /etc/ssh/sshd_config
+
 # Done with installation
 # set user, work directory and entry point
 #