Updating OpenSuse 42.3 to Leap 15

I recently updated my OpenSuse 42.3 installation to Leap 15 and while the upgrade worked fine and most of the stuff works just fine, there were some smaller issues.

DNS not working

During installation, network was working fine but after restart DNS lookups failed. Turned out that /etc/resolv.conf was not getting updated any longer. The solution was to run

netconfig -f update

once (as root) to fix the file.

USB autosuspend

This is not actually a problem with the OpenSuse update itself but I noticed that USB devices could no longer be charged. In the new kernel USB autosuspend was enabled to reduce power demands which is a good thing for longer battery runtime. A smartphone will be charged as long as it is mounted in the system. But if the device runs in charge mode only, the kernel will suspend the device right after plugging it in so it stops charging. You can disabled the power suspend individually for each USB device by writing "-1" into the autosuspend file in the /sys/ filesystem:

echo -1 >/sys/devices/pci0000:00/0000:00:1a.0/usb3/power/autosuspend

(of course adjust the address to the correct address of your device).

You can also disable it completely for all newly connected devices by writing "-1" to the file of the usbcore module:

echo -1 >/sys/module/usbcore/parameters/autosuspend

And you can also add a kernel parameter to disable it on startup:

usbcore.autosuspend=-1

Of course this will reduce battery life time a bit.

Freeze after return from hibernate

I use hibernate (or suspend-to-disk) quite often but I experienced lockups after returning from suspend. It was not happening consistently, but very often after the second or third return from suspend.

It used to work just fine for the kernel from OpenSuse 42.3. My first try to fix it was to use a newer kernel version. So I added a repository as described here. I updated to kernel 4.20 and hibernate works fine again.

[UPDATE: 2019-03-30:]

Firewall

The firewall also changed from SuSEfirewall2 to firewalld. You can migrate your configuration as described here using the tool "susefirewall2-to-firewalld". If you did not changed anything to the settings and don't care about previous settings, you should at least uninstall SuSEfirewall2 and install firewalld as it is not done automatically.