So this is an interesting one I can't figure out myself. I have Proxmox on a PowerEdge R730 with 5 NICs (4 + management). The management interface is doing its own thing so don't worry about that. Currently I have all 4 other interfaces bonded and bridged to a single IP. This IP is for my internal network (192.168.1.0/24, VLAN 1). This has been working great. I have no issues with any containers on this network. One of those containers happens to be one of two FreeIPA replicas, the other living in the cloud. I have had no issues using DNS or anything else for FreeIPA from this internal network nor from my cloud network or VPN networks.
Now, I finally have some stuff I want to toss in my DMZ network (192.168.5.0/24, VLAN 5) and so I'll just use my nice R730 to do so, right? Nope! I can get internet, I can even use the DNS server normally, but the second I go near my FreeIPA domains it all falls apart. For instance, I can get the records for example.local just fine, but the second i request ipa.example.local or ds.ipa.example.local, i get EDE 22: No Reachable Authority. This is despite the server that's being requested from being the authority for this zone. I can query the same internal DNS server from either the same internal network or a different network and it works handy dandy, but not from the R730 on another network. I can't even see the NS glue records on my public DNS root server.
I'm honestly not sure why everything except these FreeIPA domains works. Yes, I have the firewall open for it and I have added a trusted_networks ACL to Bind and allowed queries, recursion, and query_cache for this ACL. The fact it only breaks on these FreeIPA subdomains makes me think it's a forwarding issue, but shouldn't it see the NS records and keep going? It can ping all the addresses that might come up from DNS, it's showing the same SOA when I query the root domain, it just refuses to work from my IPA domains. Can someone provide any insight on this please, I'm sick and tired of trying to debug it.