Configure a Site-to-Site IPSec IKEv1 Tunnel Between an ASA and a Cisco IOS Router - Cisco
Configuring Cisco Site to Site IPSec VPN with Dynamic IP Endpoint Cisco Routers
Site-to-site IPSec VPN through NAT - Packet Pushers
IPSec Tunnel Between Cisco Routers | Site to Site VPN Between Cisco Routers
Site to Site VPN Tunnel on Cisco Router | GNS3 - Mr. Robot
Configure Site-to-Site IPSec VPN Cisco Routers | Tech Space KH
Cisco samples
Configuring IPSec Site-to-Site VPN Tunnels
Establishing IPSec Tunnels Between HUAWEI Firewalls and HUAWEI AR Routers in NAT Traversal Scenarios - HUAWEI USG Series Firewalls Interoperability Configuration Guide for VPN - Huawei