Bring water to boil in a large pot. Place beef shank into water and simmer, 1 1/2 hours. Let cool overnight. Lift meat out, trim off gristle and cut meat into medium-sized pieces; set aside. Skim fat from surface of stock, or strain through a fine sieve.

Return stock to heat, and bring to a boil. Add onions, carrots, and rutabaga. Season with salt and pepper. Simmer for 1 hour. Add potatoes, and simmer until tender, 15 to 20 minutes. Stir in the cabbage, leeks, parsley, and reserved meat. Simmer for 10 minutes, or until cabbage is tender.