systemd-networkd .network ignored within systemd-nspawn container

Question

I'm fiddling with systemd-nspawn containers on my RaspberryPi. So far booting works fine. I use the --network-veth and --network-bridge=br0 options and bridging did work well with a kvm virtual machine.

Now I want to configure the container IP to a specific address and created a /etc/systemd/network/host.network file which seems to be ignored as the container gets its IP via DHCP.

This is the file.

[Match]
Name=host0

[Network]
DHCP=no
Address=192.168.0.16/24
Gateway=192.168.0.1
DNS=8.8.8.8

systemd-networkd is running:

root@bluehost-debian:~# systemctl status systemd-networkd.service
● systemd-networkd.service - Network Service
   Loaded: loaded (/lib/systemd/system/systemd-networkd.service; enabled)
   Active: active (running) since Do 2016-09-01 21:10:54 UTC; 12min ago
     Docs: man:systemd-networkd.service(8)
 Main PID: 69 (systemd-network)
   Status: "Processing requests..."
   CGroup: /machine.slice/machine-bluecloud.scope/system.slice/systemd-networkd.service
           └─69 /lib/systemd/systemd-networkd

Sep 01 21:10:54 bluehost-debian systemd-networkd[69]: host0           : link configured
Sep 01 21:10:54 bluehost-debian systemd[1]: Started Network Service.
Sep 01 21:10:55 bluehost-debian systemd-networkd[69]: host0           : gained carrier
Sep 01 21:10:58 bluehost-debian systemd-networkd[69]: host0           : DHCPv4 address 192.168.0.143/24 via 192.168.0.1
Sep 01 21:10:58 bluehost-debian systemd-networkd[69]: host0           : link configured

udev tells me that my value for the Name field should be ok. Why is it ignored?

udevadm info /sys/class/net/host0
P: /devices/virtual/net/host0
E: DEVPATH=/devices/virtual/net/host0
E: IFINDEX=2
E: INTERFACE=host0
E: SUBSYSTEM=net

Otherwise the network works ok. Tried /etc/network/interfaces but this did not work in startup but only with ifup... (allow-hotplug host0 ...)

I'm a little stuck so help is appreciated.

Answer 1

Now I want to configure the container IP to a specific address and created a /etc/systemd/network/host.network file which seems to be ignored as the container gets its IP via DHCP.

Ok... in the container I updated systemd to latest from jessie-backports which got me networkctl. This showed me the file currently used for network configuration. which was not mine. rename my file to 00-host.network and that did the trick...

Well done.

To be clear, the problem was that host.network sorts last. You needed to provide a file with a name that sorted before the default 80-host0.network in /lib/systemd/network/, or which had the same filename (or mask it by creating a file with the same name, pointing to /dev/null).

read something about a bug with network in the container until 217... debian had 215 and in backports is 230.

Alternative: /etc/network/interfaces

Tried /etc/network/interfaces but this did not work in startup but only with ifup... (allow-hotplug host0 ...)

/etc/network/interfaces worked fine for me (with DHCP). However I worried that allow-hotplug might not work inside the container, so I had used auto host0 instead. This should be safe as host0 is created very early on by nspawn.