I'm using Google Cloud VPN gateway and attempting to connect to a CISCO ASA 5545 device on a 3rd party premise. It's a static route setup and the Cisco router is using IKE v1 only.
I have this problem where from the logs, I could see connection is established, then it says scheduling rekeying immediately after, then received INVALID_ID_INFORMATION error notify, then received DELETE for IKE_SA vpn_[PEER IP] then deleting IKE_SA vpn_[PEER IP] between [VPN PUBLIC IP]...[PEER IP]. This continues to repeat in the log.
Obviously there are configuration mismathces; the on-premise client wants me to change the encryption to AES-256 or 3des because "the device does not support AES 128". Is it even possible to change the encryption for Google Cloud VPN once you've chosen to use IKEv1?
According to the documentation https://cloud.google.com/compute/docs/vpn/advanced, IKEv1 uses aes-cbc-128 encryption, is it possible to change that to aes-256? Is it possible to make the on-premise device work with aes-128?