ipAddress property

Optional IPv4 address of network endpoint.

The IP address must belong to a VM in Compute Engine (either the primary IP or as part of an aliased IP range). If the IP address is not specified, then the primary IP address for the VM instance in the network that the network endpoint group belongs to will be used. This field is redundant and need not be set for network endpoints of type GCE_VM_IP. If set, it must be set to the primary internal IP address of the attached VM instance that matches the subnetwork of the NEG. The primary internal IP address from any NIC of a multi-NIC VM instance can be added to a NEG as long as it matches the NEG subnetwork.