I am new to Proxmox, but I am quite experienced in linux and networking.
I installed Proxmox VE 8.3 and configured a couple of VMs and LXC (including openWRT which acts as a router for the entire home network)
I discovered that both Proxmox host and LXC and VMs (without systemd-resolved) have problems with DNS requests.
Let me explain: dig requests work with any DNS server, while everything else (ping, apt update, curl) only works with DNS servers internal to the local network or with Cloudflare DNS 1.1.1.1. Any other DNS server does not respond to the queries that are made (8.8.8.8, 8.8.4.4, 9.9.9.9, etc..).
All other devices in the home network can set any DNS server and receive the answers.
I have performed several tcpdump captures on both the router and the VMs and I have noticed that the DNS requests are made correctly and go out of the WAN to the internet, however I never receive the response (except for requests made with the dig command).
Other tests I have done: I have configured a bind9 server as a dns forwarder both on a VM (inside Proxmox) and on another PC inside the network (but outside the Proxmox vmbr) and in both cases the DNS requests work.
I tried with a friend who also has a DNS server with bind9 and in this case we saw that the requests arrive at his home router, but do not arrive at the DNS server (we assume they are discarded by the kernel).
Can anyone help me?
I installed Proxmox VE 8.3 and configured a couple of VMs and LXC (including openWRT which acts as a router for the entire home network)
I discovered that both Proxmox host and LXC and VMs (without systemd-resolved) have problems with DNS requests.
Let me explain: dig requests work with any DNS server, while everything else (ping, apt update, curl) only works with DNS servers internal to the local network or with Cloudflare DNS 1.1.1.1. Any other DNS server does not respond to the queries that are made (8.8.8.8, 8.8.4.4, 9.9.9.9, etc..).
All other devices in the home network can set any DNS server and receive the answers.
I have performed several tcpdump captures on both the router and the VMs and I have noticed that the DNS requests are made correctly and go out of the WAN to the internet, however I never receive the response (except for requests made with the dig command).
Other tests I have done: I have configured a bind9 server as a dns forwarder both on a VM (inside Proxmox) and on another PC inside the network (but outside the Proxmox vmbr) and in both cases the DNS requests work.
I tried with a friend who also has a DNS server with bind9 and in this case we saw that the requests arrive at his home router, but do not arrive at the DNS server (we assume they are discarded by the kernel).
Can anyone help me?