The VPN Gateway must renegotiate the IKE security association (SA) after eight hours or less.

When a VPN gateway creates an IPsec SA, resources must be allocated to maintain the SA. These resources are wasted during periods of IPsec endpoint inactivity, which could result in the gateway’s inability to create new SAs for other endpoints, thereby preventing new sessions from connecting. The Internet Key Exchange (IKE) idle timeout may also be set to allow SAs associated with inactive endpoints to be deleted before the SA lifetime has expired, although this setting is not recommended.

Verify the VPN Gateway renegotiates the IKE security association after eight hours or less.

If the VPN Gateway does not renegotiate the IKE security association after eight hours or less, this is a finding.

Configure the VPN Gateway to renegotiate the IKE security association after eight hours or less.