High availability through an IPsec VPN connection in a single region.
Must properly configure 2 or 4 BGP tunnel from your HA VPN gateway to your peer VPN gateway or to another HA VPN gateway.
HA VPN gateway can have multiple tunnels
Each tunnel on the 2 sides of the gateway must have the same number
When HA VPN gateway is created, GCP automatically chooses two external IP addresses, one for each of its fixed number of two interfaces
from a unique address pool to support high availability.
if you run HA VPN to a remote VPN gateway on-premises for a customer, you can connect in one of the following ways:
Two on-premises VPN gateway devices: Each of the tunnels from each interface on the Cloud VPN gateway must be connected to its own peer gateway.
A single on-premises VPN gateway device with two interfaces: Each of the tunnels from each interface on the Cloud VPN gateway must be connected to its own interface on the peer gateway.
A single on-premises VPN gateway device with a single interface: Both of the tunnels from each interface on the Cloud VPN gateway must be connected to the same interface on the peer gateway.
Depending on the way that you configure route priorities for HA VPN tunnels, you can create an active/active or active/passive routing configuration.