Dear list, I am running a machine "hortensia" with a container "dahlia". As the container will be a server, I want to have one IP for hortensia and another one for dahlia. On hortensia, with dhcpcd.service and systemd-networkd both disabled, I start at boot two netctl profiles. /etc/netctl/bridge-hortensia Description="Bridge connection to container" Interface=br0 Connection=bridge BindsToInterfaces=() IP=no /etc/netctl/static-hortensia Description='hortensia static ethernet connection' Interface=enp7s0 Connection=ethernet IP=static Address=('192.168.1.87/24') Gateway=('192.168.1.254') DNS=('192.168.1.254') Then here is the result: $ ip addr 2: enp7s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 link/ether 14:da:e9:b5:7a:88 brd ff:ff:ff:ff:ff:ff inet 192.168.1.87/24 brd 192.168.1.255 scope global enp7s0 valid_lft forever preferred_lft forever inet6 fe80::16da:e9ff:feb5:7a88/64 scope link valid_lft forever preferred_lft forever 3: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default link/ether 22:6d:8b:ac:6e:31 brd ff:ff:ff:ff:ff:ff inet6 fe80::206d:8bff:feac:6e31/64 scope link valid_lft forever preferred_lft forever Two questions : - is the command output correct for br0 ? - all wiki said to bind bridge interface to my ethernet device (enp7s0). But if I modified the /etc/netctl/bridge-hortensia this way : BindsToInterfaces=(enp7s0) I have no working network on machine hortensia. Is this behavior correct ? Now let's start the dahlia container # systemd-nspawn --machine=dahlia --network-bridge=br0 -bD /dahlia' On hortensia, now a new ip addr output, as supposed it shall be (vb-dahlia): $ ip addr 2: enp7s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 link/ether 14:da:e9:b5:7a:88 brd ff:ff:ff:ff:ff:ff inet 192.168.1.87/24 brd 192.168.1.255 scope global enp7s0 valid_lft forever preferred_lft forever inet6 fe80::16da:e9ff:feb5:7a88/64 scope link valid_lft forever preferred_lft forever 3: br0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default link/ether 1a:2d:eb:58:8e:db brd ff:ff:ff:ff:ff:ff inet6 fe80::206d:8bff:feac:6e31/64 scope link valid_lft forever preferred_lft forever 5: vb-dahlia: <BROADCAST,MULTICAST> mtu 1500 qdisc noop master br0 state DOWN group default qlen 1000 link/ether 1a:2d:eb:58:8e:db brd ff:ff:ff:ff:ff:ff My issue is that br0 is DOWN and can't make it up with this command: # ip link set dev br0 up This has no effect. Then, I can see NO-CARRIER in the br0 status. Is it the expected output ? Why is br0 DOWN ? Why can't I bring it UP ? All this leaves me with a broken network on the container dahlia: $ ip addr 2: host0: <NO-CARRIER,BROADCAST,MULTICAST,ALLMULTI,NOTRAILERS,UP> mtu 1500 qdisc pfifo_fast state DOWN group default qlen 1000 link/ether b2:25:69:eb:ea:a9 brd ff:ff:ff:ff:ff:ff inet 192.168.1.94/24 brd 192.168.1.255 scope global host0 valid_lft forever preferred_lft forever host0 is DOWN with again NO-CARRIER I have no idea what part of the setup is missing. I run a custom kernel, so is there any wrong configuration on it ? The kernel is moderately customized, but maybe did I disabled some needed flag ? Thank you for help.