In libvirt, via virt-manager, I removed the built-in virtual networks.
when creating VMs, I manually enter bridge interface name sdbr11
I want VM clients be routed to my lab internal network. And only masquerade when accessing Internet.
Testing
In VM, DHCP cannot get offer.
After manually assign 192.168.22.123/24, gw 192.168.22.2, dns 8.8.8.8, access to Internet is OK.
Connect a physical machine to my switch, with vlan11 untagged, and manual IP assignment. That machine can ping VM clients and access to Internet also. (That machine also cannot get DHCP offers)
In Journal, I do not see any DHCPServer log messages.
I further testing systemd-networkd’s DHCPServer in hostapd
Same, there is no DHCP offer received by Wifi clients.
Wifi clients can access Internet using manual IP address assignment.
How to verify:
DHCPServer on a particular interface is running of not?
What kind of firewalld policy is needed to allow DHCP offers to work once DHCPServer is running?
Thank you for the pointer regarding debugging systemd-networkd. I will see what I can find in debug log enabled.
Personally, I think there is no [Match] issues in my .net* files. As when I manually assign IP address in remote machines (real and virtual), the network communication is OK.
Yes, I will try with firewall disabled in my host, once I find DHCPServer is running.