Which technology works with IPsec stateful failover?

GLBP uses per-flow load balancing with multiple active forwarders, making it incompatible with the single-active/single-standby state synchronization model that IPsec stateful failover requires.

HSRP provides the virtual IP address that both active and standby peers share, ensuring clients always connect to the same endpoint. In stateful failover mode, the active peer continuously synchronizes IKE and IPsec SA databases to the standby, so when HSRP transitions the virtual IP after a failure the standby can resume all existing sessions without requiring renegotiation.

GSS (Global Site Selector) is a DNS-based geographic load balancing appliance designed for multi-site traffic distribution, not for local peer-level IPsec session state synchronization.

VRRP is an open-standard first-hop redundancy protocol, but Cisco's stateful failover implementation for IPsec is specifically coupled with HSRP rather than VRRP on Cisco IOS and ASA platforms.