DNS Resolver Won't Work on Cellular Failover

[mdt]

Hi friends - I'm running 2.4.5 p1 and have a gateway group set up for automatic failover to a cellular connection (via a ZTE-MF833V USB card - listed as working in Netgate docs). I can route all LAN traffic to the cellular card with no problem, but as soon as I disconnect the tier 1 WAN connection, the DNS Resolver refuses to work over the cellular connection. I can still route traffic through cellular for any domains cached before failover, but nothing resolves via cellular alone. LTE provider (Google Fi) is not blocking DNS queries (confirmed via direct connection to my laptop).

I've tried:

• DNS resolver is set to all interfaces, IPv4 only
• Register DHCP leases in the DNS Resolver (Y/N)
• Forwarding Mode (Y/N)
• DNSSEC (Y/N)
• Register connected OpenVPN clients in the DNS Resolver
• Disabled pfBlockerNG
• Disabled all OpenVPN connections and routed traffic directly to the cellular gateway
• Flush connections on state change (Y/N)
• DNS servers specified for each gateway in general settings
• DNS override by DHCP (Y/N)
• Disable DNS Forwarder (Y/N)
• Cloudflare and Google DNS servers

What's odd is that it only breaks in one direction (WAN ethernet failover to cellular), but cellular to WAN ethernet causes no DNS resolver issues. I've spent 8 hours troubleshooting and reading through the forums — desperate to get it working before leaving the country — any advice?

[mdt]

I believe I was able to get this to work after binding the DNS resolver to specific Outgoing Network Interfaces instead of to ALL. Very unclear why this would be the case, but it seems to work flawlessly now.

[Cool_Corona]

@mdt said in DNS Resolver Won't Work on Cellular Failover:

I believe I was able to get this to work after binding the DNS resolver to specific Outgoing Network Interfaces instead of to ALL. Very unclear why this would be the case, but it seems to work flawlessly now.

My best bet would be GW failover but glad you got it working