Quick question regarding the Flink Operator: we're running application clusters on openshift where the GID=0 must be applied since we always get a random UID in this group as the default user. we have created our own base image of flink where we add:

&& chgrp -R 0 /opt/flink \
 && chmod -R g=u /opt/flink

we now still see these issue appearing though from the `docker-entrypoint.sh`:

sed: couldn't open temporary file /opt/flink/conf/sed7zLHN3: Read-only file system
sed: couldn't open temporary file /opt/flink/conf/sedasVKRI: Read-only file system
/docker-entrypoint.sh: line 73: /opt/flink/conf/flink-conf.yaml: Permission denied
/docker-entrypoint.sh: line 89: /opt/flink/conf/flink-conf.yaml.tmp: Read-only file system

which basically comes from this section in the

docker-entrypoint.sh

set_config_option() {
  local option=$1
  local value=$2

  # escape periods for usage in regular expressions
  local escaped_option=$(echo ${option} | sed -e "s/\./\\\./g")

  # either override an existing entry, or append a new one
  if grep -E "^${escaped_option}:.*" "${CONF_FILE}" > /dev/null; then
        sed -i -e "s/${escaped_option}:.*/$option: $value/g" "${CONF_FILE}"
  else
        echo "${option}: ${value}" >> "${CONF_FILE}"
  fi
}

prepare_configuration() {
    set_config_option jobmanager.rpc.address ${JOB_MANAGER_RPC_ADDRESS}
    set_config_option blob.server.port 6124
    set_config_option query.server.port 6125

    if [ -n "${TASK_MANAGER_NUMBER_OF_TASK_SLOTS}" ]; then
        set_config_option taskmanager.numberOfTaskSlots ${TASK_MANAGER_NUMBER_OF_TASK_SLOTS}
    fi

    if [ -n "${FLINK_PROPERTIES}" ]; then
        echo "${FLINK_PROPERTIES}" >> "${CONF_FILE}"
    fi
    envsubst < "${CONF_FILE}" > "${CONF_FILE}.tmp" && mv "${CONF_FILE}.tmp" "${CONF_FILE}"
}

where it tries to override some values such as the numberOfTasksSlots if the ENV var is provided. the operator though - from what I've seen only works via the

flink-conf.yaml

and not via the ENV vars. what would be the suggestions to get this fixed? can we somehow correct the access rights? or should we simply override the

docker-entrypoint.sh

in our base image and let it ignore the ENV vars completely? or is there an even better approach we're not seeing yet... do we maybe use the wrong flink image which is not compatible with the operator? i'd assume that they must be compatible since the

docker-entrypoint.sh

would always try to overwrite flink-conf.yaml but the configMap isn't mutable...