@Stefan, I just did the test according to your description, I didn't reproduce your problem:
On my rpi4B with 4G ram and without ethernet cable connect, I installed the 1012 kernel: On the rpi4 board: ubuntu@ubuntu:~$ uname -a Linux ubuntu 5.3.0-1012-raspi4 #14 SMP Thu Nov 21 11:46:38 UTC 2019 aarch64 aarch64 aarch64 GNU/Linux ubuntu@ubuntu:~$ cat /etc/netplan/50-cloud-init.yaml # This file is generated from information provided by # the datasource. Changes to it will not persist across an instance. # To disable cloud-init's network configuration capabilities, write a file # /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg with the following: # network: {config: disabled} network: version: 2 renderer: networkd wifis: wlan0: dhcp4: yes dhcp6: no access-points: "mywifi": password: "mypassword" ubuntu@ubuntu:~$ sudo netplan apply ubuntu@ubuntu:~$ ifconfig lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1000 (Local Loopback) RX packets 44 bytes 3738 (3.7 KB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 44 bytes 3738 (3.7 KB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 wlan0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500 ether dc:a6:32:0e:9b:c5 txqueuelen 1000 (Ethernet) RX packets 605 bytes 724475 (724.4 KB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 540 bytes 72600 (72.6 KB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 ubuntu@ubuntu:~$ ifconfig lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1000 (Local Loopback) RX packets 44 bytes 3738 (3.7 KB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 44 bytes 3738 (3.7 KB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 wlan0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.1.109 netmask 255.255.255.0 broadcast 192.168.1.255 inet6 fe80::dea6:32ff:fe0e:9bc5 prefixlen 64 scopeid 0x20<link> ether dc:a6:32:0e:9b:c5 txqueuelen 1000 (Ethernet) RX packets 615 bytes 726200 (726.2 KB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 558 bytes 75051 (75.0 KB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 On my host machine: hwang4@hwang4-Vostro-5390:~/work/mainline/build/eoan-rpi/ubuntu-eoan/patch$ ssh ubuntu@192.168.1.109 The authenticity of host '192.168.1.109 (192.168.1.109)' can't be established. ECDSA key fingerprint is SHA256:ABndCbsaeSF4OTivweZvtSSmvzbtA9j1t1qUjQF2CBg. Are you sure you want to continue connecting (yes/no)? yes Warning: Permanently added '192.168.1.109' (ECDSA) to the list of known hosts. ubuntu@192.168.1.109's password: Welcome to Ubuntu 19.10 (GNU/Linux 5.3.0-1012-raspi4 aarch64) * Documentation: https://help.ubuntu.com * Management: https://landscape.canonical.com * Support: https://ubuntu.com/advantage System information as of Thu Nov 21 14:07:33 UTC 2019 System load: 2.39 Processes: 142 Usage of /: 52.4% of 7.00GB Users logged in: 1 Memory usage: 8% IP address for wlan0: 192.168.1.109 Swap usage: 0% * Kata Containers are now fully integrated in Charmed Kubernetes 1.16! Yes, charms take the Krazy out of K8s Kata Kluster Konstruction. https://ubuntu.com/kubernetes/docs/release-notes 31 updates can be installed immediately. 25 of these updates are security updates. To see these additional updates run: apt list --upgradable Last login: Thu Nov 21 14:06:29 2019 ubuntu@ubuntu:~$ ls focal-preinstalled-server-armhf+raspi3.img.xz ubuntu@ubuntu:~$ uname -a Linux ubuntu 5.3.0-1012-raspi4 #14 SMP Thu Nov 21 11:46:38 UTC 2019 aarch64 aarch64 aarch64 GNU/Linux ** Changed in: linux (Ubuntu) Importance: Undecided => High ** Changed in: linux (Ubuntu) Status: Confirmed => Incomplete ** Package changed: linux (Ubuntu) => linux-raspi2 (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1853030 Title: No connection through SSH over WIfi after kernel update To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-raspi2/+bug/1853030/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs