I've personally aged a large cheese wheel for several months, and it's common to see cracks develop over time. This usually means the cheese is losing moisture as it matures, which can affect texture and flavor. When I noticed cracks, I gently cleaned the wheel's surface to remove any dried residues or mold, ensuring to use a soft cloth and avoid harsh scrubbing that could damage the rind. One useful trick I've found is to keep the cheese stored in a cool, humid environment like a wine fridge or a dedicated cheese storage box. High humidity helps prevent excessive drying that leads to cracking. If the crack is deep or the cheese looks like it could spoil, trimming the affected area can be helpful to keep the rest of the cheese safe to eat. Remember, cracking is a natural part of the aging process for many hard cheeses like Parmesan. It doesn't necessarily mean your cheese is spoiled or unusable. Regularly inspecting your cheese and maintaining proper storage will extend its life, allowing you to enjoy its rich flavors longer. Feel free to share your experiences or ask questions about cheese aging and care; it's a fascinating journey that every cheeselover should explore!