Comment 2 for bug 1870410

From /var/log/syslog:

ubuntu@ubuntu:~$ grep wlan0 /var/log/syslog
Apr 2 14:18:19 ubuntu systemd[1]: Found device /sys/subsystem/net/devices/wlan0.
Apr 2 14:18:19 ubuntu systemd[1]: Started WPA supplicant for netplan wlan0.
Apr 2 14:18:19 ubuntu kernel: [ 22.355445] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
Apr 2 14:18:19 ubuntu wpa_supplicant[1028]: wlan0: Trying to associate with SSID 'javelin7'
Apr 2 14:18:19 ubuntu wpa_supplicant[1028]: wlan0: Associated with 50:c7:bf:15:c0:93
Apr 2 14:18:19 ubuntu wpa_supplicant[1028]: wlan0: CTRL-EVENT-CONNECTED - Connection to 50:c7:bf:15:c0:93 completed [id=0 id_str=]
Apr 2 14:18:19 ubuntu wpa_supplicant[1028]: wlan0: CTRL-EVENT-SUBNET-STATUS-UPDATE status=0
Apr 2 14:18:19 ubuntu systemd-networkd[1109]: wlan0: Gained IPv6LL
Apr 2 14:18:19 ubuntu systemd-networkd[1109]: wlan0: Link DOWN
Apr 2 14:18:19 ubuntu systemd-networkd[1109]: wlan0: Lost carrier
Apr 2 14:18:19 ubuntu systemd-networkd[1109]: wlan0: Link UP
Apr 2 14:18:19 ubuntu systemd-networkd[1109]: wlan0: Gained carrier
Apr 2 14:18:19 ubuntu systemd-networkd[1109]: wlan0: Connected WiFi access point: javelin7 (50:c7:bf:15:c0:93)
Apr 2 14:18:19 ubuntu systemd-networkd[1109]: wlan0: Re-configuring with /run/systemd/network/10-netplan-wlan0.network
Apr 2 14:18:19 ubuntu systemd-networkd[1109]: wlan0: IPv6 successfully enabled
Apr 2 14:18:19 ubuntu systemd-networkd[1109]: wlan0: IPv6 successfully enabled
Apr 2 14:18:19 ubuntu systemd-networkd[1109]: wlan0: DHCP4 CLIENT: Failed to attach event: Device or resource busy
Apr 2 14:18:19 ubuntu systemd-networkd[1109]: wlan0: Failed
Apr 2 14:18:19 ubuntu systemd-networkd-wait-online[1110]: managing: wlan0
Apr 2 14:18:19 ubuntu systemd-networkd-wait-online[1110]: managing: wlan0
Apr 2 14:18:19 ubuntu systemd-networkd-wait-online[1110]: managing: wlan0
Apr 2 14:18:19 ubuntu systemd-networkd-wait-online[1110]: managing: wlan0