Place pork, ham hocks, kielbasa, 1 of the onions, garlic, 1 tsp. salt, peppercorns, and bay leaves in a large, heavy pot with water to cover. Bring to a boil over medium-high heat. Reduce heat and gently simmer for 2 hours, skimming fat and foam.
Add remaining 5 onions, leeks, carrots, turnips, sausages, and potatoes, and bring to a simmer. Cook over medium-low heat until vegetables are almost tender, about 30 minutes. Add cabbage; cook 10 minutes more.
Remove meat and vegetables and keep warm in a low oven. Reduce stock over high heat for 10 minutes. Adjust seasoning.
Slice meat and sausages and place in the center of a deep platter; surround with vegetables. Ladle some broth over the dish and sprinkle with salt and pepper. Serve with remaining broth and toasted bread.
