Disable IPv6 at kernel boot time

- IPv6 is currently unsupported

Author: struanb

README.md

@@ -191,6 +191,7 @@ In the below summary of RunCVM's current main features and limitations, [+] is u
       - [+] `--hostname` (or `-h`) is supported
       - [-] Only one network (that which is assigned during `docker run`) is supported per container. There is no support for `docker network connect`.
       - [-] `--network=host` and `--network=container:name|id` are not supported
+      - [-] IPv6 is not supported
    - Execution environment
       - [+] `--user` (or `-u`) is supported
       - [?] `--workdir` (or `-w`) is supported

runcvm-scripts/runcvm-ctr-qemu

@@ -114,6 +114,9 @@ if [ "$RUNCVM_BIOS_DEBUG" != "1" ]; then
   OPTS+=(-fw_cfg opt/org.seabios/etc/sercon-port,string=0)
 fi
 
+# Disable IPv6, which is currently unsupported, at kernel boot time
+APPEND+=(ipv6.disable=1)
+
 ARGS=(
   "${OPTS[@]}"
   -no-user-config