Overlapping CIDR Blocks - How to Find Them Before VPC Peering or Transit Gateway Refuses the Connection, What AWS, Azure and Google Cloud Each Reject, and the Four Ways Out (Renumber, Secondary CIDR,

This blog discusses how to identify and resolve overlapping CIDR blocks in cloud networking, focusing on AWS, Azure, and Google Cloud. It explains the implications of CIDR overlap for VPC peering and offers four methods to resolve these conflicts. Additionally, it emphasizes the importance of maintaining an accurate inventory of networks to avoid overlaps before they occur.