Multi-Wan dns failover cpanel and http proxy issues

[medico6601]

Hello everyone
I'm using OPNSense since winter and it's the most stable and reliable product I've ever seen, 200 days uptime, great job. Had some issues with new Intel nics pci-x, went for older ones.

So I have two requirements and I don't know how to solve them:

1. Failover multi wan setup with proxy
แทงบอลเงินสด
The network computers have internet access through http proxy (not transparent) only.
The network file server has full internet access and port forwarding.
When the main gateway fails OPNSense switches the backup one, but the computers no longer have internet access, only the server has.
How can this be fixed?

2. I'm achieving dns failover using a small c# service which updates the IP for the subdomain automatically in cpanel.
The subdomain points to both OPNSense wan IP, backup and main, I've added port forwarding rules for both gateways.
The dns resolution is provided by a hosting company, short TTL.
The simple c# service running on the file server does a "my IP" check each minute and if that has changed it updates it with a https request to the hosting cpanel API.

How can this process be performed on OPNSense, is it possible to trigger a script when the main gateway failed, or can I write a plug-in for that?
Where to start with this?

Thank you