I have kea and virt-manager installed. I have one virtual network
defined, and it is set to come up at boot. It does not, apparently
because kea grabs the virtual interface before dnsmasq can grab it.

I have to shut kea's dhcp4 server down, then start the virtual network,
then start the kea dhcp4 server up again.

According to the kea docs, I should be able to tell the kea dhcp4 server
which interfaces to bind to with the "interfaces-config" option. This
does not appear to be working; kea grabs the virtual interface
before dnsmasq can anyway.

This is on trixie as updated.

charles@hawk:~$ pre kea-dhcp4 virt-manager
kea-dhcp4-server 2.6.3-1+deb13u1 amd64
virt-manager 1:5.0.0-5+deb13u1 all
charles@hawk:~$

I don't see any relevant reports in https://bugs.debian.org/cgi-bin/pkgreport.cgi?dist=trixie;package=kea-dhcp4-server

"Dhcp4": {
// Add names of your network interfaces to listen on.
"interfaces-config": {
// See section 8.2.4 for more details. You probably want to add just
// interface name (e.g. "eth0" or specific IPv4 address on that
// interface name (e.g. "eth0/192.168.100.12").
// "interfaces": [ "wlp2s0" ]
"interfaces": [ "enp3s0" ]

// Kea DHCPv4 server by default listens using raw sockets. This ensures
// all packets, including those sent by directly connected clients
// that don't have IPv4 address yet, are received. However, if your
// traffic is always relayed, it is often better to use regular
// UDP sockets. If you want to do that, uncomment this line:
// "dhcp-socket-type": "udp"
},



--
Does anybody read signatures any more?

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https://charlescurley.com/blog/

--- PyGate Linux v1.5.19
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

On Thu, 27 Aug 2026 22:01:41 +0200
john doe <johndoe65534@mail.com> wrote:

"interfaces": [ "enp3s0" ]

- How is this interface configured (ip addressing)?

Network Manager, using static addressing. So no DHCP.

- Do you see anything interesting if you use "-d" when- starting Kea?

I assume you mean the kea dhcp4 server. Well, I see a lot of stuff.

I wasn't able to start it from the command line, even with su. So I
edited the service to add the -d. Searching on 'interface' I see:

Aug 27 16:41:28 hawk kea-dhcp4[29687]: DEBUG DHCP4_CONFIG_RECEIVED
received configuration { ? "interfaces-config": { "interfaces": [ "enp3s0/192.168.100.6" ] }, ? .
?
Aug 27 16:41:28 hawk kea-dhcp4[29687]: INFO DHCPSRV_CFGMGR_USE_ADDRESS listening on address 192.168.100.6, on interface enp3s0

and that's it. It doesn't appear to claim any others, probably because
I shut down the virtual network. But the virtual network refuses to
start.

I ran 'journalctl -f', and tried to start up the virtual network.
Nothing in the trace indicating that kea tried to grab the virtual
interface.

The network's definition has the following:

<dnsmasq:options>
<dnsmasq:option value="interface=virbr0"/>
<dnsmasq:option value="except-interface=lo,enp3s0"/>
</dnsmasq:options>

To me, that's more of a question for Kea or Libvirt!

If I don't get any satisfaction here I will try those two.

--
Does anybody read signatures any more?

https://charlescurley.com
https://charlescurley.com/blog/

--- PyGate Linux v1.5.19
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)