On a Google Cloud Platform (GCP) infrastructure, some subnet addresses are reserved for items specific to the platform. CDV will store IP addresses reserved in subnets by GCP as IP addresses with corresponding types in a BlueCat Address Manager (BAM) network.
CDV supports the import of IPv4 reserved IP addresses for GCP. When discovering reserved IP addresses, if a specific reserved address is already used in Address Manager, CDV will log an error in the CDV error log file.
Within a subnet, GCP reserves the first two and last two IP addresses in each subnet primary IPv4 address range. GCP lets you use all addresses in secondary IPv4 address ranges. CDV will map the reserved IP addresses to IP addresses on BAM as follows:
IPv4 networks
| Unusable address | GCP | BAM | Example |
|---|---|---|---|
| First address | Network address | Network ID | 10.1.1.0 from CIDR range 10.1.1.0/24 |
| Second address | Reserved by GCP for the default gateway | Gateway address | 10.1.1.1 from CIDR range 10.1.1.0/24 |
| Second-to-last address | Reserved by GCP for future use | Reserved address |
10.1.1.254 from CIDR range 10.1.1.0/24 |
| Last address | Network broadcast address | Broadcast address | 10.1.1.255 from CIDR range 10.1.1.0/24 |