the networking is configured via systemd-networkd. bonding module is loaded with 'max_bonds=0' to address upcoming systemd change https://github.com/systemd/systemd/issues/6184
pre-upgrade: # networkctl IDX LINK TYPE OPERATIONAL SETUP 1 lo loopback carrier unmanaged 2 eth0 ether carrier configuring 3 eth1 ether carrier configuring 4 bond0 ether routable configured 5 bond0.200 ether routable configured # ip link 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eth0: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 9000 qdisc mq master bond0 state UP mode DEFAULT group default qlen 1000 link/ether 5a:42:ff:c5:26:61 brd ff:ff:ff:ff:ff:ff 3: eth1: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 9000 qdisc mq master bond0 state UP mode DEFAULT group default qlen 1000 link/ether 5a:42:ff:c5:26:61 brd ff:ff:ff:ff:ff:ff 4: bond0: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 9000 qdisc noqueue state UP mode DEFAULT group default qlen 1000 link/ether 5a:42:ff:c5:26:61 brd ff:ff:ff:ff:ff:ff 5: bond0.200@bond0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000 link/ether 5a:42:ff:c5:26:61 brd ff:ff:ff:ff:ff:ff interfaces(.d) and netplan are empty and unused/disabled /etc/systemd/network: # cat eth1.network [Match] Name=eth1 [Network] Bond=bond0 # cat eth0.network [Match] Name=eth0 [Network] Bond=bond0 # cat bond0.netdev [NetDev] Name=bond0 Kind=bond [Bond] Mode=802.3ad MIIMonitorSec=0.1s LACPTransmitRate=fast UpDelaySec=0.2s DownDelaySec=0.2s # cat bond0.network [Match] Name=bond0 [Address] Address=192.168.1.100/24 [Route] Gateway=192.168.1.1 [Network] VLAN=bond0.200 [Link] MTUBytes=9000 # cat bond0.200.netdev [NetDev] Name=bond0.200 Kind=vlan [VLAN] Id=200 # cat bond0.200.network [Match] Name=bond0.200 [Address] Address=10.10.0.100/16 [Route] Gateway=10.10.0.1 [Link] MTUBytes=9000 After upgrade: # networkctl IDX LINK TYPE OPERATIONAL SETUP 1 lo loopback carrier unmanaged 2 eth0 ether carrier configuring 3 eth1 ether carrier configuring 4 bond0 ether routable configured 5 bond0.200 ether routable configured However, the link of eth0, eth1 and the bond and vlan interface changes to NOARP # ip link 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eth0: <BROADCAST,MULTICAST,NOARP,SLAVE,UP,LOWER_UP> mtu 9000 qdisc mq master bond0 state UP mode DEFAULT group default qlen 1000 link/ether 5a:42:ff:c5:26:61 brd ff:ff:ff:ff:ff:ff 3: eth1: <BROADCAST,MULTICAST,NOARP,SLAVE,UP,LOWER_UP> mtu 9000 qdisc mq master bond0 state UP mode DEFAULT group default qlen 1000 link/ether 5a:42:ff:c5:26:61 brd ff:ff:ff:ff:ff:ff 4: bond0: <BROADCAST,MULTICAST,NOARP,MASTER,UP,LOWER_UP> mtu 9000 qdisc noqueue state UP mode DEFAULT group default qlen 1000 link/ether 5a:42:ff:c5:26:61 brd ff:ff:ff:ff:ff:ff 5: bond0.200@bond0: <BROADCAST,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000 link/ether 5a:42:ff:c5:26:61 brd ff:ff:ff:ff:ff:ff ** Bug watch added: github.com/systemd/systemd/issues #6184 https://github.com/systemd/systemd/issues/6184 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1727301 Title: 229-4ubuntu20 added ARP option breaks existing bonding interfaces Status in systemd package in Ubuntu: Confirmed Bug description: this breaks existing configurations with bonding on upgrading from 229-4ubuntu19 to 229-4ubuntu20 on xenial as bond interfaces are now by default configured without ARP. Hence you suddenly lose network connectivity on upgrade. Very bad for a SRU. Plus adding "ARP=yes" to the Link section of a .network file does not work. Before this update, bond interfaces (specifically 802.3ad) were defaulting to ARP enabled. After the upgrade, they are created with NOARP set on the link. pre-upgrade: eth0: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> eth1: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> bond0: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> post-upgrade: eth0: <BROADCAST,MULTICAST,NOARP,SLAVE,UP,LOWER_UP> eth1: <BROADCAST,MULTICAST,NOARP,SLAVE,UP,LOWER_UP> bond0: <BROADCAST,MULTICAST,NOARP,MASTER,UP,LOWER_UP> Linux cnode11 4.4.0-97-generic #120-Ubuntu SMP Tue Sep 19 17:28:18 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1727301/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp