Example documentation for IPSec tunnels from Nuagenetworks nsg e200 devices

Hi,
we have several issues to create stable IPSec tunnels form Nuagenetworks e200 devices to Zscaler.
Does anyone have successful created stable tunnels from such devices and can share the configuration.
Most errors we have is DPD timeouts and IPSec re-negotiations.

We are using IPSec with username and PSK.
Thank you & best regards
Andreas