AZ104-Q: Peering VNets with overlapping address spaces
Q: You want to peer two VNets whose address spaces overlap (both use
10.0.0.0/16). Will peering succeed?
- A) Yes — peering automatically handles overlapping ranges
- B) No — VNets with overlapping address spaces cannot be peered ✓
- C) Yes, but only if they are in different regions
- D) Yes, if you use a VPN gateway instead
Answer: B. VNet peering requires non-overlapping address spaces. If two VNets (or their subnets) overlap in IP ranges, the route between them is ambiguous and peering fails. Overlapping ranges are a common cause of peering errors. A VPN gateway does not resolve overlapping address spaces either — it has the same requirement. Peering also requires that neither VNet uses the other’s address space.
Why it helps
Always check address-space overlap before peering. If the ranges overlap, you must re-address or use a different topology — the exam loves this trap.