Subject: Assistance Needed for Multi-WAN Setup with Cloudflare Tunnel for Mail Serv

Hello Cloudflare Community,

I am currently using a Cloudflare Tunnel due to my Multi-WAN setup on my OPNsense router. My primary ISP connection (fiber optic) occasionally experiences outages, so I have connected a secondary mobile 4G/5G router to ensure continuous access to my web services. This part of my setup is functioning as expected.

However, I am encountering an issue with my mail server, which is behind a mail gateway. I would like my mail service to also failover seamlessly, just like my web services.

I came across a discussion from a few years ago where it was mentioned that this might not be feasible because the Cloudflare Tunnel configuration creates a CNAME DNS record, whereas an MX record requires an A record.

My question is: Is there a way to configure my setup so that my SMTP server remains accessible even if my primary connection fails? Any advice or guidance on this matter would be greatly appreciated.

Thank you in advance for your help!

Best regards,