How many instances does Azure virtual network gateway have in active-standby configuration?

very Azure VPN gateway consists of two instances in an active-standby configuration. For any planned maintenance or unplanned disruption that happens to the active instance, the standby instance would take over (failover) automatically, and resume the S2S VPN or VNet-to-VNet connections. The switch over will cause a brief interruption. For planned maintenance, the connectivity should be restored within 10 to 15 seconds. For unplanned issues, the connection recovery will be longer, about 1 to 3 minutes in the worst case. For P2S VPN client connections to the gateway, the P2S connections will be disconnected and the users will need to reconnect from the client machines.