Gateway/Routing Problems on the Opnsense itself after upgrade from 23.7 to 24.1.

[unclesam87]

Hello,

Today, I upgraded a firewall from version 23.7 to 24.1.5. After the reboot, everything looked fine at first glance, but I noticed the following issues:

1. Both ISP gateways are reported as offline according to monitoring.
1.1. Occasionally, one of the gateways shows up as online, but this only lasts for a short time – the reason is not yet clear.
2. Firmware updates are not possible because DNS resolution is failing.
2.1 DNS lookup via the firewall yields no results if:
2.2. Only the hostname is entered.
2.3. If 1.1.1.1 is entered as the DNS server, it returns: Error: error sending query: Error creating socket.
2.4. If the AD DNS server is specified, the lookup is successful.
3. VPN issues:
3.1. Sometimes the VPN only works over one of the two ISPs, although both were functioning previously.
4.Pings (perhaps I am testing incorrectly here):
4.1. Pinging 1.1.1.1 from the firewall's IP fails.
4.2. Pinging a local address from the firewall's IP works.
4.3. Pinging 1.1.1.1 from the ISP interface's IP (Vodafone) fails.
4.4. Pinging 1.1.1.1 from the ISP gateway's IP (Vodafone) fails.
4.5. The same result occurs for the other ISP.
5. All clients are working perfectly as of now!
6. All web services are reachable without issues.
7. Both ISPs use static IP addresses with subnets – no IPv6 or DHCP is used here.
7.1. There is a WAN group – perhaps there is an error here?
8. OpenVPN: I can only access OpenVPN through one ISP, although it used to work with both.
8.1. Additionally, if I change settings on the gateways, even if I revert them, it sometimes changes which ISP allows VPN access.
8.2 The ISPs are Plusnet (fiber) and Vodafone (cable) – I think it's unlikely that the problem lies with them.
9.1. Both ISPs are configured with static IP subnets in Opnsense.
9.2. Multi-WAN configuration with monitoring IPs.

I have tried many things and even reverted to the last working configuration. I think I am becoming too close to the issue and would greatly appreciate constructive and organized suggestions on how to resolve this problem.

[unclesam87]

problem "solved": we reinstalled it with an 24.7 image and loaded the config file.