Ensure VCN CIDR prefix overlaps with other VCNs in your tenancy or with your organizations private IP network ranges. The explanation is that a VCN CIDR prefix is the range of IPv4 addresses that can be used within the VCN and its subnets. The VCN CIDR prefix should not overlap with other VCNs in your tenancy or with your organization's private IP network ranges, as this can cause routing conflicts and connectivity issues. You should choose a VCN CIDR prefix that is large enough to accommodate your current and future needs, but not too large to waste IP addresses. You can use any of the private IPv4 address ranges specified in RFC 1918 for your VCN CIDR prefix.