Shred the cabbage thinly to resemble saurkraut using a knife, madeleine or food processor.
Cut onion in half lengthwise and slice into thin half moons.
Put the shredded cabbage in a large bowl, add the shredded onion and entire contents of the 2 sauerkraut packages. (Do not drain or rinse the sauerkraut.).
Sprinkle in the caraway seeds.
Using your hands, mix well. It will seem to be too much cabbage for the amount of sauerkraut but do not be concerned.
Place a 2" layer of sauerkraut mixture in the bottom of a large Dutch oven, stockpot or non-aluminum kettle. Layer the pork ribs on the sauerkraut mixture and cover with 1/3 of the remaining sauerkraut mix.
Cut the keilbasa into 6 - 8 pieces and layer in pot. Cover with another 1/3 of the sauerkraut mixture.
Add a layer of hotdogs, cut in half if desired, and top with remaining sauerkraut mixture. Pour any juices that remain in the bowl into the pot.
Cover and simmer over a very low heat for 2 1/2 - 3 hours. At the end of the cooking time you should not be able to tell what started out as cabbage or onion from what was originally sauerkraut.
Note: A pork roast can substituted for the boneless ribs, kielbasa and hotdogs. If using a roast brown it in a separate skillet and double the thickness of the base layer of the sauerkraut mixture.