pfSense

When using IKEv2, dpd_timeout is ignored and instead the global charon.retransmit_* is used to determine the timeout thresholds of the IKE connection. As is, the timeout can last for several minutes.

The retransmission options should be user-configurable. This would help, for example, in HA failover scenarios where a low retransmission timeout could result in a significantly quicker IPsec reconnection.

https://wiki.strongswan.org/projects/strongswan/wiki/ConnSection
https://wiki.strongswan.org/projects/strongswan/wiki/Retransmission
https://wiki.strongswan.org/projects/strongswan/wiki/Swanctlconf

Related issues:
https://redmine.pfsense.org/issues/5355