Unable to activate the ethernet connection after upgrading to Ubuntu 18.04

I just upgraded from Ubuntu 17.10 to 18.04, and my wired network does not work (whereas my wifi connection works just fine).

My interface seems correctly detected by the system:

sudo lshw -C network

Gives me this

*-network                 
       description: Ethernet interface
       produit: RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller
       fabriquant: Realtek Semiconductor Co., Ltd.
       identifiant matériel: 0
       information bus: pci@0000:02:00.0
       nom logique: enp2s0
       version: 15
       numéro de série: b0:6e:bf:02:e2:8d
       taille: 100Mbit/s
       capacité: 1Gbit/s
       bits: 64 bits
       horloge: 33MHz
       fonctionnalités: pm msi pciexpress msix bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full firmware=rtl8168h-2_0.0.2 02/26/15 latency=0 link=yes multicast=yes port=MII speed=100Mbit/s
       ressources: irq:126 portE/S:d000(taille=256) mémoire:ef204000-ef204fff mémoire:ef200000-ef203fff
  *-network
       description: Interface réseau sans fil
       produit: Realtek Semiconductor Co., Ltd.
       fabriquant: Realtek Semiconductor Co., Ltd.
       identifiant matériel: 0
       information bus: pci@0000:03:00.0
       nom logique: wlp3s0
       version: 00
       numéro de série: 40:9f:38:28:95:31
       bits: 64 bits
       horloge: 33MHz
       fonctionnalités: pm msi pciexpress bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=r8822be driverversion=4.15.0-20-generic firmware=N/A ip=192.168.42.70 latency=0 link=yes multicast=yes wireless=IEEE 802.11
       ressources: irq:129 portE/S:c000(taille=256) mémoire:ef100000-ef10ffff

(with a bunch of other interfaces, created by docker and/or virtualbox, i guess)

But it seems that the system is not able to get any response from the DHCP client, only for my ethernet interface.

journalctl -u NetworkManager

mai 09 21:29:48 guillaume NetworkManager[12863]:   [1525894188.7918] device (enp2s0): state change: ip-config -> deactivating (reason 'user-requested', sys-ifa
mai 09 21:29:48 guillaume NetworkManager[12863]:   [1525894188.7924] audit: op="device-disconnect" interface="enp2s0" ifindex=2 pid=1807 uid=1000 result="succe
mai 09 21:29:48 guillaume NetworkManager[12863]:   [1525894188.7930] device (enp2s0): state change: deactivating -> disconnected (reason 'user-requested', sys-
mai 09 21:29:48 guillaume NetworkManager[12863]:   [1525894188.8338] dhcp4 (enp2s0): canceled DHCP transaction, DHCP client pid 13504
mai 09 21:29:48 guillaume NetworkManager[12863]:   [1525894188.8338] dhcp4 (enp2s0): state changed unknown -> done
mai 09 21:29:48 guillaume NetworkManager[12863]:   [1525894188.8737] dispatcher: (18) 01-ifupdown failed (failed): Script '/etc/NetworkManager/dispatcher.d/01-
mai 09 21:29:51 guillaume NetworkManager[12863]:   [1525894191.1413] device (enp2s0): Activation: starting connection 'Connexion filaire 1' (314fe0f7-6356-4f63
mai 09 21:29:51 guillaume NetworkManager[12863]:   [1525894191.1416] audit: op="connection-activate" uuid="314fe0f7-6356-4f63-aadc-9cb947b26528" name="Connexio
mai 09 21:29:51 guillaume NetworkManager[12863]:   [1525894191.1421] device (enp2s0): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'm
mai 09 21:29:51 guillaume NetworkManager[12863]:   [1525894191.1431] device (enp2s0): state change: prepare -> config (reason 'none', sys-iface-state: 'managed
mai 09 21:29:51 guillaume NetworkManager[12863]:   [1525894191.1444] device (enp2s0): state change: config -> ip-config (reason 'none', sys-iface-state: 'manag
mai 09 21:29:51 guillaume NetworkManager[12863]:   [1525894191.1450] dhcp4 (enp2s0): activation: beginning transaction (timeout in 45 seconds)
mai 09 21:29:51 guillaume NetworkManager[12863]:   [1525894191.1489] dhcp4 (enp2s0): dhclient started with pid 13562
mai 09 21:29:51 guillaume dhclient[13562]: DHCPDISCOVER on enp2s0 to 255.255.255.255 port 67 interval 3 (xid=0x5c5d0e34)
mai 09 21:29:54 guillaume dhclient[13562]: DHCPDISCOVER on enp2s0 to 255.255.255.255 port 67 interval 6 (xid=0x5c5d0e34)

If I launch sudo dhclient enp2s0 the command just never ends.

Any idea?


A recent update fixed the issue.