Failed to query for metadata size

You must pull the MMT image to both your source MSR system and your target MSR system, otherwise the migration will fail with the following error message:

Failed to query RethinkDB for total metadata size: failed to convert query
response to int: strconv.Atoi: parsing "": invalid syntax
Continuing without total metadata size ...

To remedy this you must pull the MMT image to each of the two systems, using the following commands:

docker login -u <username>
docker pull