Don't rely on systemd to run minimega components

See moby/moby#42275.

docker/Dockerfile

@@ -11,7 +11,7 @@ COPY ./src    ./src
 RUN ./build.bash
 
 
-FROM jrei/systemd-ubuntu:20.04
+FROM ubuntu:20.04
 
 RUN apt update && apt install -y \
   dnsmasq iproute2 isc-dhcp-client \
@@ -31,19 +31,20 @@ COPY --from=gobuilder /minimega/bin/miniweb  /opt/minimega/bin/miniweb
 COPY --from=gobuilder /minimega/bin/miniccc     /opt/minimega/bin/miniccc
 COPY --from=gobuilder /minimega/bin/miniccc.exe /opt/minimega/bin/miniccc.exe
 
-# For the sake of consistency, let's go ahead and include protonuke in the image
-# too so we can easily grab a copy if/when necessary.
+# For the sake of consistency, let's go ahead and include protonuke and
+# minirouter in the image too so we can easily grab a copy if/when necessary.
 COPY --from=gobuilder /minimega/bin/protonuke     /opt/minimega/bin/protonuke
 COPY --from=gobuilder /minimega/bin/protonuke.exe /opt/minimega/bin/protonuke.exe
+COPY --from=gobuilder /minimega/bin/minirouter    /opt/minimega/bin/minirouter
 
-COPY ./misc/web /opt/minimega/misc/web
+COPY ./misc/web  /opt/minimega/misc/web
+COPY ./docker/mm /usr/local/bin/mm
 
-ADD docker/minimega.service /etc/systemd/system/minimega.service
-ADD docker/miniweb.service  /etc/systemd/system/miniweb.service
+COPY ./docker/start-minimega.sh /start-minimega.sh
 
-WORKDIR /etc/systemd/system/multi-user.target.wants
-
-RUN ln -s ../minimega.service \
-  && ln -s ../miniweb.service
+RUN chmod +x /usr/local/bin/mm \
+  && chmod +x /start-minimega.sh
 
 WORKDIR /opt/minimega
+
+CMD ["/start-minimega.sh"]

docker/README.md

@@ -8,36 +8,47 @@
 
 ### Build the minimega docker image
 
-> NOTE: Currently, only minimega, miniweb, miniccc, and protonuke will exist in the minimega docker image. If you need additional binaries, add them to the Dockerfile using the `COPY --from=gobuilder …` directive.
+> NOTE: Currently, only minimega, miniweb, miniccc, minirouter, and protonuke
+> will exist in the minimega docker image. If you need additional binaries, add
+> them to the Dockerfile using the `COPY --from=gobuilder …` directive.
 
-> NOTE: The docker image needs to be built from the base directory of the minimega repository.
+> NOTE: The docker image needs to be built from the base directory of the
+> minimega repository.
 
   ```bash
   $ docker build -t minimega -f docker/Dockerfile .
   ```
 
 ### Start the minimega docker container
 
-> NOTE: The additional privileges and system mounts (e.g. /dev) are required for the openvswitch process to run inside the container and to allow minimega to perform file injections.
+> NOTE: The additional privileges and system mounts (e.g. /dev) are required for
+> the openvswitch process to run inside the container and to allow minimega to
+> perform file injections.
+
+> NOTE: If the `deploy launch` minimega command is used to initialize a
+> multi-node minimega cluster, then a directory containing SSH keys will likely
+> need to be mounted as a volume as well (and can be read-only). An example
+> would be `-v /root/.ssh:/root/.ssh:ro`.
 
 ```bash
-docker run -d -it \
+docker run -d \
   --name minimega \
   --hostname minimega \
   --privileged \
   --cap-add ALL \
   -p 9000:9000/udp \
   -p 9001:9001 \
-  -v /tmp/minimega:/tmp/minimega \
-  -v /var/log/minimega:/var/log/minimega \
   -v /dev:/dev \
   -v /lib/modules:/lib/modules:ro \
-  -v /sys/fs/cgroup:/sys/fs/cgroup:ro \
-  --health-cmd "minimega -e version" \
+  -v /var/log/minimega:/var/log/minimega \
+  -v /tmp/minimega:/tmp/minimega \
+  --health-cmd "mm version" \
   minimega
 ```
 
-The container runs systemd as PID 1, which takes care of starting openvswitch, minimega, and miniweb.
+The container runs the `start-minimega.sh` script as PID 1, which takes care of
+starting openvswitch, miniweb, and finally minimega. This means the minimega
+logs will be available in the container logs via Docker.
 
 ---
 
@@ -75,3 +86,25 @@ $ source ~/.bash_aliases
 
 miniweb gets started in the container automatically.
 
+### minimega configuration
+
+By default, the following values are set for minimega:
+
+```
+MM_BASE=/tmp/minimega
+MM_FILEPATH=/tmp/minimega/files
+MM_BROADCAST=255.255.255.255
+MM_PORT=9000
+MM_DEGREE=2
+MM_CONTEXT=minimega
+MM_LOGLEVEL=info
+MM_LOGFILE=/var/log/minimega.log
+```
+
+These values can be overwritten either by passing environment variables to
+Docker when starting the container or by binding a file to
+`/etc/default/minimega` in the container that contains updated values.
+
+> NOTE: If a value is specified both as an environment variable to Docker and in
+> the file bound to `/etc/default/minimega`, the value in
+> `/etc/default/minimega` will be used.

docker/docker-compose.yml

@@ -1,6 +1,9 @@
 version: '3.7'
 services:
   minimega:
+    build:
+      context: ../
+      dockerfile: docker/Dockerfile
     image: minimega
     container_name: minimega
     hostname: minimega
@@ -19,10 +22,8 @@ services:
     volumes:
     - /dev:/dev
     - /lib/modules:/lib/modules:ro
-    - /sys/fs/cgroup:/sys/fs/cgroup:ro
     - /etc/localtime:/etc/localtime:ro
     - /tmp/minimega:/tmp/minimega
     - /var/log/minimega:/var/log/minimega
-    - /root/.ssh:/root/.ssh:ro
     healthcheck:
-      test: minimega -e version
+      test: mm version

docker/mm

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+exec /opt/minimega/bin/minimega -e "$@"

docker/start-minimega.sh

@@ -0,0 +1,28 @@
+#!/bin/bash
+
+/usr/share/openvswitch/scripts/ovs-ctl start
+
+/opt/minimega/bin/miniweb -root=/opt/minimega/misc/web -addr=0.0.0.0:9001 &
+
+: "${MM_BASE:=/tmp/minimega}"
+: "${MM_FILEPATH:=/tmp/minimega/files}"
+: "${MM_BROADCAST:=255.255.255.255}"
+: "${MM_PORT:=9000}"
+: "${MM_DEGREE:=2}"
+: "${MM_CONTEXT:=minimega}"
+: "${MM_LOGLEVEL:=info}"
+: "${MM_LOGFILE:=/var/log/minimega.log}"
+
+[[ -f "/etc/default/minimega" ]] && source "/etc/default/minimega"
+
+/opt/minimega/bin/minimega \
+  -force \
+  -nostdin \
+  -base=${MM_BASE} \
+  -filepath=${MM_FILEPATH} \
+  -broadcast=${MM_BROADCAST} \
+  -port=${MM_PORT} \
+  -degree=${MM_DEGREE} \
+  -context=${MM_CONTEXT} \
+  -level=${MM_LOGLEVEL} \
+  -logfile=${MM_LOGFILE}