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Highlights of YaST Development Sprint 90

December 5th, 2019 by

As usual, during this sprint we have been working on a wide range of topics. The release of the next (open)SUSE versions is approaching and we need to pay attention to important changes like the new installation media or the /usr/etc and /etc split.

Although we have been working on more stuff, we would like to highlight these topics:

  • Support for the new SLE installation media.
  • Proper handling of shadow suite settings.
  • Mount points handling improvements.
  • Help others to keep the Live Installation working.
  • Proper configuration of console fonts.
  • Better calculation of minimum and maximum sizes while resizing ext2/3/4 filesystems.
  • Small fixes in the network module.

The New Online and Full SLE Installation Media

The upcoming Service Pack 2 of SUSE Linux Enterprise products will be released on two media types: Online and Full.

On the one hand, the Online medium does not contain any repository at all. They will be added from a registration server (SCC/SMT/RMT) after registering the selected base product. The Online medium is very small and contains only the files needed for booting the system and running the installer. On the other hand, the Full medium includes several repositories containing base products and several add-ons, which can help to save some bandwidth.

Obviously, as the installer is the same for both media types, we need to adapt it to make it work properly in all scenarios. This is an interesting challenge because the code is located in many YaST packages and at different places. Keep also in mind that the same installer needs to also work with the openSUSE Leap 15.2 product. That makes another set of scenarios which we need to support (or at least not to break).

The basic support is already there and we are now fine-tuning the details and corner cases, improving the user experience and so on.

Proper Handling of Shadow Suite Settings

A few weeks ago, we anticipated that (open)SUSE would split system’s configuration between /usr/etc and /etc directories. The former will contain vendor settings and the latter will define host-specific settings.

One of the first packages to be changed was shadow, which stores now its default configuration in /usr/etc/login.defs. The problem is that YaST was not adapted in time and it was still trying to read settings only from /etc/login.defs

During this sprint, we took the opportunity to fix this behavior and, what is more, to define a strategy to adapt the handling of other files in the future. In this case, YaST will take into account the settings from /usr/etc directory and it will write its changes to a dedicated /etc/login.defs.d/70-yast.conf file.

Missing Console Font Settings

The YaST team got a nice present this year (long before Christmas) thanks to Joaquín, who made an awesome contribution to the YaST project by refactoring the keyboard management module. Thanks a lot, Joaquín!

We owe all of you a blog entry explaining the details but, for the time being, let’s say that now the module plays nicely with systemd.

After merging those changes, our QA team detected that the console font settings were not being applied correctly. Did you ever think about the importance of having the right font in the console? The problem was that the SCR agent responsible for writing the configuration file for the virtual consoles was removed. Fortunately, bringing back the deleted agent was enough to fix the problem, so your console will work fine again.

Helping the Live Installation to Survive

Years ago, the YaST Team stopped supporting installation from the openSUSE live versions due to maintainability reasons. That has not stopped others from trying to keep the possibility open. Instead of fixing the old LiveInstallation mode of the installer, they have been adapting the live versions of openSUSE to include the regular installer and to be able to work with it.

Sometimes that reveals hidden bugs in the installer that nobody had noticed because they do not really affect the supported standard installation procedures. In this case, YaST was not always marking for installation in the target system all the packages needed by the storage stack. For example, the user could have decided to use Btrfs and still the installer would not automatically select to install the corresponding btrfsprogs package.

It happened because YaST was checking which packages were already installed and skipping them. That check makes sense when YaST is running in an already installed system and is harmless when performed in the standard installation media. But it was tricky in the live media. Now the check is skipped where it does not make sense and the live installation works reasonably well again.

A More Robust YaST Bootloader

In order to perform any operation, the bootloader module of YaST first needs to inspect the disk layout of the system to determine which devices allocate the more relevant mount points like /boot or the root filesystem. The usage of Btrfs, with all its exclusive features like subvolumes and snapshots, has expanded the possibilities about how a Linux system can look in that regard. Sometimes, that meant YaST Bootloader was not able to clearly identify the root file system and it just crashed.

"Missing '/' mount point" error

Fortunately, those scenarios are reduced now to the very minimum thanks to all the adaptations and fixes introduced during this sprint regarding mount points detection. But there is still a possibility in extreme cases like unfinished rollback procedures or very unusual subvolumes organization.

So, in addition to the mentioned improvements in yast2-storage-ng, we have also instructed yast2-bootloader to better deal with those unusual Btrfs scenarios, so it will find its way to the root file system, even if it’s tricky. That means the “missing ‘/’ mount point” errors should be gone for good.

But in case we overlooked something and there is still an open door to reach the same situation again in the future, we also have improved YaST to display an explanation and quit instead of crashing. Although we have done our best to ensure this blog entry will be the only chance for our users to see this new error pop-up.

YaST2 Bootloader: root file sytem not found

Improving the Detection of Mount Points

As mentioned above, improving the detection of mount points helped to prevent some problems that were affecting yast2-bootloader. However, that is not the only module that benefits from such changes.

When you run some clients like the Expert Partitioner, they automatically use the libstorage-ng library to discover all your storage devices. During that phase, libstorage-ng tries to find the mount points for all the file systems by inspecting /etc/fstab and /proc/mounts files. Normally, a file system is mounted only once, either at boot time or manually by the user. For the first case, both files /etc/fstab and /proc/mounts would contain an entry for the file system, for example:

$ cat /etc/fstab
/dev/sda1  /  ext4  defaults  0  0

$ cat /proc/mounts
/dev/sda1 / ext4 rw,relatime 0 0

In the example above, libstorage-ng associates the / mount point to the file system which is placed on the partition /dev/sda1. But, what happens when the user bind-mounts a directory? In such a situation, /proc/mounts would contain two entries for the same device:

$ mound /tmp/foo /mnt -o bind
$ cat /proc/mounts
/dev/sda1 / ext4 rw,relatime 0 0
/dev/sda1 /mnt ext4 rw,relatime 0 0

In the Expert Partitioner, that file system will appear as mounted at /mnt instead of /. So it will look like if your system did not have the root file system after all!

This issue was solved by improving the heuristic for associating mount points to the devices. Now, the /etc/fstab mount point is assigned to the device if that mount point also appears in the /proc/mounts file. That means, if a device is included in the /etc/fstab and the device is still mounted at that location, the /etc/fstab mount point takes precedence.

As a bonus, and also related to mount points handling, now the Expert Partitioner is able to detect the situation where, after performing a snapshot-based rollback, the system has not been rebooted. As a result, it will display a nice and informative message to the user.

System not rebooted after snapshot rollback

Improved Calculation of Minimum and Maximum Sizes for ext2/3/4

If you want to resize a filesystem using YaST, it needs to find out the minimum and maximum sizes for the given filesystem. Until now, the estimation for ext2/3/4 was based on the statvfs system call and it did not work well at all.

Recently, we have improved YaST to use the value reported by resize2fs as the minimum size which is more precise. Additionally, YaST checks now the block size and whether the 64bit feature is on to calculate the maximum size.

Polishing the Network Module

As part of our recent network module refactorization, we have improved the workflow of wireless devices configuration, among other UI changes. Usually, these changes are controversial and, as a consequence, we received a few bug reports about some missing steps that are actually not needed anymore. However, checking those bugs allowed us to find some small UI glitches, like a problem with the Authentication Mode widget.

Moreover, we have used this sprint to drop the support for some deprecated device types, like Token Ring or FDDI. Below you can see how bad the device type selection looks now. But fear not! We are aware and we will give it some love during the next sprint.

Network Device Type Selection

Conclusions

The last sprint of the year is already in progress. This time, we are still polishing our storage and network stacks, improving the migration procedure, and fixing several miscelaneous issues. We will give you all the details in two weeks through our next sprint report. Until then, have a lot of fun!

Highlights of YaST Development Sprints 88 and 89

November 22nd, 2019 by

A More User Friendly Role Selector Dialog

Step by step, we continue improving the user experience making use of the newly added widgets to libyui. This sprint was the turn to update the role selection dialog to use the new item selector introduced during the sprint 87. Apart from looking better as it can be seen in the screenshots below, there are two immediate improvements:

  • the vertical scroll, when present, is respected after selecting a role (instead of “jumping to the beginning”), and
  • the selected role (if any) will be visible when arriving at the dialog even when the list is quite long or the available space too short.
Before After

What is more, updating the dialog was also useful for us to realize about some needed improvements for the widget itself, mentioned in the next section. Quite a productive change 🙂

When one Bit is not Enough: The CustomStatusItemSelector

A few weeks ago, we wrote about the new ItemSelector widget that is finding its way into YaST user interfaces. It turned out that just a simple on/off status is not enough in some cases, so we had to extend that concept. For example, software modules may have dependencies, and we want to show the difference between one that was explicitly selected by the user and one that was auto-selected because some other software module requires it.

This kind of shook the foundations of the underlying classes; all of a sudden a bit is no longer just a bit, but it needs to be broken down into even smaller pieces. Well, we cheated; we now use integer values instead. Most of the class hierarchy still only uses 0 and 1, but the new YCustomStatusItemSelector also supports using higher numbers for application-defined purposes.

For each possible status value, the application defines the name of the icon to be displayed (for graphical UIs like the Qt UI), the text equivalent (for text mode / the NCurses UI), and an optional nextStatus which tells the widget what status to cycle to when the user changes the status of an item with a mouse click or with the keyboard. A value of -1 lets the application handle this.

So this is not a one-trick-pony that is useful only for that one use case (the software modules), but a generic tool that might find good uses in other places all over YaST as well.

Usage examples: C++, Ruby.

Snapper and Machine-readable Output

Most likely you already know snapper, a great tool to work with your filesystem snapshots. Some third-party scripts and tools (e.g., YaST) use the snapper CLI to get some information, but generally, snapper generates an output intended to be human-readable. Sometimes that could cause some troubles in scripts checking the snapper output. Now on, snapper also offers CLI options to generate its output in a machine-readable format, i.e., CSV and JSON. Please, check this post for more information about those new options.

Fix Boot Problems with Remote Encrypted Devices

Since we adopted systemd, the management during system boot of encrypted devices on top of network-based devices like iSCSI or FCoE disks has been less than optimal. But now we are happy to announce that we have put all the pieces together to make the experience as smooth as possible.

One of the main responsibilities of systemd is sorting the actions performed during boot and setting the dependencies between them. For example, if there are encrypted devices, systemd will first ask you for the password and activate the devices to afterwards mount the file system contained in those encrypted devices. Systemd should be able to distinguish when an encrypted device is based on a network-based storage device and, thus, can only be initialized after the network is up. In some cases that detection failed (for example network block device based mounts, such as iSCSI and FCoE disks) and systemd got stuck before initializing the network waiting for the device to be available.

Recently, SLE and openSUSE Leap has incorporated support for specifying the _netdev option in the /etc/crypttab file. With such option, systemd will recognize the encrypted device as network-based and will only try to activate it after setting up the network. That’s analogous to the corresponding _netdev option in /etc/fstab that has been already there for quite some time and that can be used to defer when a device is mounted. For it to work properly, the _netdev option must be present in all the relevant entries of both crypttab and fstab.

And that’s exactly what YaST will do now in openSUSE Tumbleweed and upcoming releases of both SLE and openSUSE Leap. From now on, the _netdev option will be added fstab for all mount points depending (directly or indirectly) on the network. In addition, that option (and also the noauto and nofail ones) will be propagated from fstab to all the corresponding crypttab entries.

This should mark the end of a dark age of encrypted iSCSI and FCoE devices timing out during boot.

AutoYaST Support for Random and Pervasive Encryption

Back in October, we announced that YaST got support for new encryption methods like random or pervasive encryption. At that time, AutoYaST was out of scope because we wanted to have a stable (and tested) API first. Fortunately, the time has come and now AutoYaST supports these encryption mechanisms.

Starting in autoyast2 4.2.17, you can specify the encryption method using a crypt_method element, as shown in the example below. Possible values are luks1 (regular LUKS1 encryption), pervasive_luks2 (pervasive volume encryption), protected_swap (encryption with volatile protected key), secure_swap (encryption with volatile secure key) and random_swap (encryption with volatile random key).

    <drive>
     <type config:type="symbol">CT_DISK</type>
     <use>all</use>
     <partitions config:type="list">
      <partition>
       <size>20G</size>
       <mount>/</mount>
       <filesystem config:type="symbol">ext4</filesystem>
       <crypt_method config:type="symbol">luks1</crypt_method> <!-- default method if crypt_key is defined -->
       <crypt_key>S3CR3T</crypt_key>
      </partition>
      <partition>
       <size>1G</size>
       <mount>swap</mount>
       <crypt_method config:type="symbol">random_swap</crypt_method> <!-- set encryption method -->
      </partition>
     </partitions>
    </drive>

As we want AutoYaST to be as user-friendly as possible, it will try to help you if you do some mistake setting the encryption configuration as when in the screenshot below.

Finally, the old crypt_fs element is deprecated, although it stills works for backward-compatibility reasons. Basically, it is equivalent to setting crypt_method to luks1.

Improve Support for AutoYaST Guided Partitioning

When it comes to partitioning, we can categorize AutoYaST use cases into three different levels:

  • Automatic partitioning: the user does not care about the partitioning and trusts in AutoYaST to do the right thing.
  • Guided partitioning: the user would like to set some basic settings (use LVM, set an encryption password, etc.)
  • Expert partitioning: the user specifies how the layout should look, although a complete definition is not required.

To some extent, it is like using the regular installer where you can skip the partitioning screen and trust in YaST, use the Guided Proposal, or define the partitioning layout through the Expert Partitioner.

The second level (Guided partitioning) was introduced in AutoYaST with the release of SUSE Linux Enteprise 15 (and Leap 15.0) but it was not documented at all. Additionally, although it was working as designed at first sight, it was far from being that useful.

This sprint with invested quite some time improving the documentation (kudos to our awesome documentation team) and the behaviour. Now, if you want to set up an LVM system without having the specify all the details, you can use the following snippet in your profile:

<general>
  <storage>
    <lvm config:type="boolean">true</lvm>
  </storage>
</general>

If you are interested in the available options, you can check the documentation draft.

using YaST firstboot wizard in WSL

November 21st, 2019 by

When starting a WSL distribution for the first time, a text prompt for user name and password appears:

The code for that is partially in the Windows launcher. The Windows side actually prompts for the user name:
https://github.com/microsoft/WSL-DistroLauncher/blob/master/DistroLauncher/DistroLauncher.cpp#L44

and passes it to ‘adduser’:
https://github.com/microsoft/WSL-DistroLauncher/blob/1f8551f7e2ea22bba2e6fb02f01e7a5f7fb757f3/DistroLauncher/DistributionInfo.cpp#L14

That seems to be a Debian specific tool that also prompts for a password. We don’t have it in openSUSE. When done, the Windows part actually calls into the Linux environment again with ‘id -u’ to get the uid of the added user:
https://github.com/microsoft/WSL-DistroLauncher/blob/1f8551f7e2ea22bba2e6fb02f01e7a5f7fb757f3/DistroLauncher/DistributionInfo.cpp#L44

So in order to also prompt for the password we’d have to write a wrapper like the Debian one or implement another prompt in the launcher. Implementing such a prompt in Windows code seems boring to me. When writing a wrapper, I’d do something dialog based to make it look more fancy. There’s already jeos-firstboot that does something similar already and more. But then the WSL image doesn’t have to be really minimal, which means we have YaST!

So even though WSL doesn’t really boot as it has no systemd it would be still possible to run the YaST firstboot wizard on first start. What modules it launches is configurable via xml file. So leaving out hardware/VM specific things like network configuration it works pretty well:


For the launcher to know the name of the created user a small YaST module was needed to write the name into /run/wsl_firstboot_uid. The launcher fetches it from there.

Using the YaST firstboot wizard also allows to use e.g. the existing registration dialogs on SLE or add other useful configuration steps. One feature I have in mind would be for example is the role selection screen to offer some pre defined package selections for WSL use cases.

Tumbleweed and Leap appx files to test this are available from download.opensuse.org. Keep in mind that one needs to import the certificates used by OBS for signing first.

Highlights of YaST Development Sprint 87

October 23rd, 2019 by

It’s time for another YaST team report! Let’s see what’s on the menu today.

  • More news and improvements in the storage area, specially regarding encryption support.
  • Some polishing of the behavior of YaST Network.
  • New widgets in libYUI.
  • A look into systemd timers and how we are using them to replace cron.
  • And a new cool tool for developers who have to deal with complex object-oriented code!

So let’s go for it all.

Performance Improvements in Encrypted Devices

As you may know, we have recently extended YaST to support additional encryption mechanisms like volatile encryption for swap devices or pervasive encryption for data volumes. You can find more details in our blog post titled "Advanced Encryption Options Land in the YaST Partitioner".

Those encryption mechanisms offer the possibility of adjusting the sector size of the encryption layer according to the sector size of the disk. That can result in a performance boost with storage devices based on 4k blocks. To get the best of your systems, we have instructed YaST to set the sector size to 4096 bytes whenever is possible, which should improve the performance of the encrypted devices created with the recently implemented methods.

Additionally, we took the time to improve the codebase related to encryption, based on the lessons we learned while implementing volatile and pervasive encryption. We also performed some additional tests and we found a problem that we are already fixing in the sprint that has just started.

Other improvements related to encryption

One of those lessons we have learnt recently is that resizing a device encrypted with a LUKS2 encryption layer works slightly different to the traditional LUKS1 case. With LUKS2 the password must be provided in the moment of resizing, even if the device is already open and active. So we changed how libstorage-ng handles the passwords provided by the user to make it possible to resize LUKS2 devices in several situations, although there are still some cases in which it will not be possible to use the YaST Partitioner to resize a LUKS2 device.

As a side effect of the new passwords management, now the process that analyzes the storage devices at the beginning of the installation should be more pleasant in scenarios like the one described in the report of bug#1129496, where there are many encrypted devices but the user doesn’t want to activate them all.

And talking about improvements based on our users’ feedback, we have also adapted the names of the new methods for encrypting swap with volatile keys, as suggested in the comments of our already mentioned previous blog post. We also took the opportunity to improve the corresponding warning messages and help texts.

New name and description for encryption with volatile keys

Network and Dependencies Between Devices

Similar to encryption, the network backend is another area that needed some final adjustments after the big implementation done in the previous sprints. In particular, we wanted to improve the management of devices that depend on other network devices, like VLANs (virtual LANs) or bridges.

Historically, YaST has simply kept the name of the device as a dependency, even if such device does not exist any longer. That leaded to inconsistent states. Now the dependencies are updated dynamically. If the user renames a device, then it’s automatically renamed in all its dependencies. If the user deletes a device that is needed by any other one, YaST will immediately ask the user whether to modify (in the case of bonding and bridges) or to remove (in the case of VLANs) those dependent devices.

New libYUI Widget: ItemSelector

Now that we mention the user experience, it’s fair to note that it has been quite a while since we created the last new widget for libYUI, our YaST UI toolkit. But we identified a need for a widget that lets the user select one or many from a number of items with not only a short title, but also a descriptive text for each one (and optionally an icon), and that can scroll if there are more items than fit on the screen.

So say hello to the new SingleItemSelector.

SingleItemSelector in graphical mode

As you would expect from any libYUI widget, there is also a text-based (ncurses) alternative.

SingleItemSelector in text mode

Please, note the screenshots above are just short usage examples. We are NOT planning to bring back the desktop selection screen. On the other hand, now we have the opportunity to make a prettier screen to select the computer role. Stay tuned for more news about that.

There is also an alternative version of the new widget that allows to select several items. The unsurprisingly named MultiItemSelector.

MultiItemSelector in graphical mode

Which, of course, also comes with an ncurses version.

MultiItemSelector in text mode

In the near future, we are planning to use that for selecting products and add-on modules. But this kind of widgets will find other uses as well.

Fun with Systemd Timers

And talking about the close future, many of you may know there is a plan coming together to replace the usage of cron with systemd timers as the default mechanism for (open)SUSE packages to execute periodic tasks.

In our case, we decided to start the change with yast2-ntp-client, which offers the possibility to synchronize the system time once in a while. So let’s take a look to how systemd timers work and how we used them to replace cron.

When defining a service in systemd it is possible to specify a type for that service to define how it behaves. When started, a service of type oneshot will simply execute some action and then finish. Those services can be combined with the timers, which invoke any service according to monotonous clock with a given cadence. To make that cadence configurable by the user, the YaST module overrides the default timer with another one located at /etc/systemd/system.

As a note for anyone else migrating to systemd timers, our first though was to use the EnvironmentFile directive instead of overriding the timer. But that seems to not be possible for timers.

One clear advantage of using a systemd service to implement this is the possibility of specifying dependencies and relations with other services. In our case, that allows us to specify that one time synchronization cannot be used if the chrony daemon is running, since they would both conflict. So the new system is slightly more complex than a one-liner cron script, but it’s also more descriptive and solid.

And another tip for anyone dealing with one-shot services and systemd timers, you can use systemd-cat to catch the output of any script and redirect it to the systemd journal.

Everybody Loves Diagrams

But apart from tips for sysadmins and packagers, we also have some content for our fellow developers. You know YaST is a huge project that tries to manage all kind of inter-related pieces. Often, the average YaST developer needs to jump into some complex module. Code documentation can help to know your way around YaST internals that you don’t work with every day. To generate such documentation, we use the YARD tool, and its output is for example here, for yast-network. Still, for large modules with many small classes, this is not enough to get a good overview.

Enter yard-medoosa, a plugin for YARD that automatically creates UML class diagrams, clickable to get you to the classes textual documentation.

The yast2-network medoosa

It is still a prototype but it has proven useful for navigating a certain large pull request. We hope to soon tell you about an improved version.

More Solid Device Names in fstab and crypttab

Back to topics related to storage management, you surely know there are several ways to specify a device to be mounted in the /etc/fstab file or a device to be activated in the /etc/crypttab. Apart from using directly the name of the device (like /dev/sda1) or any of its alternative names based on udev, you can also use the UUID or the label of the file-system or of the LUKS device.

By default, YaST will use the udev path in s390 systems and the UUID in any other architecture. Although that’s something that can be configured modifying the /etc/sysconfig/storage file or simply using this screen of the Partitioner, which makes possible to change how the installation (both the Guided Setup and the Expert Partitioner) writes the resulting fstab and crypttab files.

Changing the way devices are referenced

But, what happens when the default option (like the udev path) is not a valid option for some particular device? So far, YaST simply used the device name (e.g. /dev/sda1) as an immediate fallback. That happened at the very end of the process, when already writing the changes to disk.

We have improved that for Tumbleweed, for SLE-15-SP1 (which implies Leap 15.1) and for the upcoming versions of (open)SUSE. Now, if the default value is not suitable for a particular device because the corresponding udev path does not exists, because using a given name is incompatible with the chosen encryption method, or for any other reason, YaST will fall back to the most reasonable and stable alternative. And it will do it from the very beginning of the process, being immediately visible in the Partitioner.

Stay Tuned for More… and Stay Communicative

As usual, when we publish our sprint report we are already working on the next development sprint. So in approximately two weeks you will have more news about our work, this time likely with a strong focus in AutoYaST.

Don’t forget to keep providing us feedback. As commented above, it’s very valuable for us and we really use it as an input to plan subsequent development sprints.

Advanced Encryption Options Land in the YaST Partitioner

October 9th, 2019 by

Welcome to a new sneak peek on the YaST improvements you will enjoy in SLE-15-SP2 and openSUSE Leap 15.2… or much earlier if you, as most YaST developers, are a happy user of openSUSE Tumbleweed.

In our report of the 84th sprint we mentioned some changes regarding the encryption capabilities of the YaST Partitioner, like displaying the concrete encryption technology or the possibility to keep an existing encryption layer.

Keeping the previous encryption layer

And the report of sprint 85 contained a promise about a separate blog post detailing the new possibilities we have been adding when it comes to create encrypted devices.

So here we go! But let’s start with a small disclaimer. Although some of the new options are available for all (open)SUSE users, it’s fair to say that this time the main beneficiaries are the users of s390 systems, which may enjoy up to four new ways of encrypting their devices.

Good Things don’t Need to Change

As you may know, so far the YaST Partitioner offered an “Encrypt Device” checkbox when creating or editing a block device. If such box is marked, the Partitioner asks for an encryption password and creates a LUKS virtual device on top of the device being encrypted.

LUKS (Linux Unified Key Setup) is the standard for Linux hard disk encryption. By providing a standard on-disk-format, it facilitates compatibility among distributions. LUKS stores all necessary setup information in the partition header, enabling to transport or migrate data seamlessly. So far, there are two format specifications for such header: LUKS1 and LUKS2. YaST uses LUKS1 because is established, solid and well-known, being fully compatible with the (open)SUSE installation process and perfectly supported by all the system tools and by most bootloaders, like Grub2.

You should not fix what is not broken. Thus, in most cases, the screen for encrypting a device has not changed at all and it still works exactly in the same way under the hood.

Editing an encrypted device

But using an alternative approach may be useful for some use cases, and we wanted to offer an option in the Partitioner for those who look for something else. So in some special cases that screen will include a new selector to choose the encryption method. Let’s analyze all those new methods.

Volatile Swap Encryption with a Random Key

When a swap device has been marked to be encrypted, the user will be able to choose between “Regular LUKS1” and “Volatile Encryption with Random Key”. Both options will be there for swap devices on all hardware architectures. The first option simply uses the classical approach described above.

Selecting the encryption method

The second one allows to configure the system in a way in which the swap device is re-encrypted on every boot with a new randomly generated password.

Encrypt swap with a random password

Some advanced users may point that configuring such a random encryption for swap was already possible in versions of openSUSE prior to Leap 15.0. But the procedure to do so was obscure to say the least. The encryption with a random password was achieved by simply leaving blank the “Enter a Password” field in the encryption step. The exact implications were not explained anywhere in the interface and the help text didn’t mention all the risks.

Now the same configuration can be achieved with a more explicit interface, relevant information is provided as you can see in the screenshot below and some extra internal controls are in place to try to limit the potential harm.

Help text for the random swap method

With this approach, the key used to encrypt the content of the swap is generated on every boot using /dev/urandom which is extremely secure. But you can always go a bit further…

Swap Encryption with Volatile Protected AES Keys

One of the nice things about having a mainframe computer (and believe us there are MANY nice things) is the extra security measures implemented at all levels. In the case of IBM Z or IBM LinuxONE that translates into the so-called pervasive encryption. Pervasive encryption is an infrastructure for end-to-end data protection. It includes data encryption with protected and secure keys.

In s390 systems offering that technology, the swap can be encrypted on every boot using a volatile protected AES key, which offers an extra level of security compared to regular encryption using data from /dev/urandom. This document explains how to setup such system by hand. But now you can just use YaST and configure everything with a single click, as shown in the following screenshot.

Encrypting swap with volatile protected keys

The good thing about this method is that you can use it even if your s390 system does not have a CCA cryptographic coprocessor. Oh, wait… you may not know what a cryptographic coprocessor is. Don’t worry, just keep reading.

Pervasive Encryption for Data Volumes

Have you ever wondered how James Bond would protect his information from the most twisted and resourceful villains? We don’t know for sure (or, at least, we are supposed to not disclosure that information), but we would bet he has an s390 system with at least one Crypto Express cryptographic coprocessor configured in CCA mode (shortly referred as a CCA coprocessor).

Those dedicated pieces of hardware, when properly combined with CPU with CPACF support, make sure the information at-rest in any storage device can only be read in the very same system where that information was encrypted. They even have a physical mechanism to destroy all the keys when the hardware is removed from the machine, like the self-destruction mechanisms in the spy movies!

As documented here, the process to enjoy the full power of pervasive encryption for data volumes in Linux can be slightly complex… unless you have the YaST Partitioner at hand!

Pervasive volume encryption

As you can see in the screenshot above, the process with YaST is as simple as choosing “Pervasive Volume Encryption” instead of the classic LUKS1 that YaST uses regularly for non-swap volumes. If YaST finds in the system a secure AES key already associated to the volume being encrypted, it will use that key and the resulting encryption device will have the DeviceMapper name specified for that key. If such secure keys don’t exist, YaST will automatically register a new one for each volume.

Help for pervasive volume encryption

Pervasive encryption can be used on any volume of the system, even the root partition.

I want it all!

So far we have seen you can use protected AES keys for randomly encrypting swap and registered secure keys for protecting data volumes. But what if you want your swap to be randomly encrypted with a volatile secure AES key? After all, you have already invested time and money installing those great CCA coprocessors, let’s use them also for the random swap encryption!

If your hardware supports it, when encrypting the swap you will see a “Volatile Encryption with Secure Key” option, in addition to the other four possibilities commented above. As easy as it gets!

All possible methods for encrypting a swap

More Booting Checks in non-s390 Systems

As described in the help for pervasive volume encryption showed above, that encryption method uses LUKS2 under the hood. So we took the opportunity to improve the Partitioner checks about encryption and booting. Now, in any architecture that is not s390 the following warning will be displayed if the expert partitioner is used to place the root directory in a LUKS2 device without a separate plain /boot.

New check for booting

As mentioned, that doesn’t apply to s390 mainframes. The usage of zipl makes possible to boot Linux in those systems as long as the kernel supports the encryption technology, independently of the Grub2 (lack of) capabilities.

What’s next?

We are still working to smooth off the rough edges of the new encryption methods offered by YaST and to add AutoYaST support for them. You may have noticed that most of the improvements currently implemented will only directly benefit s390 systems… even just a subset of those. But at the current stage, we already have built the foundation for a new era of encryption support in YaSTland.

We are thinking about adding more encryption methods that could be useful for all (open)SUSE users, with general support for LUKS2 being an obvious candidate. But that’s not something we will see in the short term because there are many details to iron up first in those technologies to make then fit nicely into the current installation process.

But hey, meanwhile you can play with all the other new toys!

Highlights of YaST Development Sprint 85

September 26th, 2019 by

Refactored Network on its way to Tumbleweed

A few weeks ago we submitted the first round of changes to the network module to Tumbleweed. At that point, it was still using the old data model for most operations (except routing and DNS handling) and a lot of work remained to be done.

We have been working hard on improving the overall quality of this module and we will submit an updated (and much improved) version in the upcoming days. To summarize, here are some highlights:

  • Completed the new data model (support for TUN/TAP, bridges, bonding, VLANs, etc.).
  • New wireless configuration workflow.
  • Revamped support for interface renaming and driver assignment, including better udev rule handling.
  • Fixed /etc/hosts handling when switching from static to DHCP based configuration.
  • Many small fixes in several areas.

Are we done with the refactoring? No, we are still working on improving S390 support and fixing small issues, but most of the work is already done.

Of course, as soon as we finish, we will publish a blog entry with the gory details. But, as we know that you love screenshots, let us show you a handful of them.

Although we have not introduced big user interface changes, we have tried to improve small things, like properly displaying whether an interface belongs to a VLAN or hiding the "Hardware" tab for virtual interfaces.

DNS resolution not working during installation, or: openQA is different

When we got a bug report that DNS resolution was not working during installation (since SLE-15 apparently), a solution seemed straightforward: /run/netconfig/resolv.conf was missing because the /run directory was not mirrored (bind-mounted) into the target system. That’s a task that used to be done by yast-storage in times before SLE-15 and was for some unknown reason forgotten when we implemented yast-storage-ng. A one-line fix was easily done, tested, and submitted.

Or so it seemed.

A few days later we got reports from SLE openQA that tests started to fail with this patch. Nothing networking related but the installation did not finish because the 10 seconds countdown dialog (‘going to reboot’) at the very end of the installation was frozen. The UI didn’t accept any input whatsoever. But whatever we tried, the issue was not reproducible outside openQA. YaST logs from openQA showed that /run got mounted as planned and was cleanly unmounted at the end of the installation – before that frozen dialog. So no clue so far and the issue was set aside for a while. Until the same reports came in from Tumbleweed testing. It was clearly linked to this one-line patch. But how?

It stayed a mystery until a chat with an openQA expert shed some light on the issue. What we thought was happening was: openQA stopped the dialog (by pressing a button) and when it tried to go on the OK button did not respond anymore. What we learned does actually happen is this: openQA stops the dialog, then switches from X to the text console, collects logs, switches back to X, and then the UI does not respond anymore. So that was quite an essential point missing.

And with this it was easily reproduced outside openQA: the X logs showed that the X server lost all its input devices after the switch. And that was because someone had deleted the whole /run directory. The YaST logs didn’t contain a hint (of course not, would have been too easy) but grepping the sources found the place where YaST deleted the directory.

The code had been added after complaints that the installation left a cluttered /run directory – of course the installation did leave files there, since it was forgotten to bind-mount the directory. So once the mentioned patch bind-mounted it again the deletion code cleaned up not /run in the installation target system but the real /run as well – cutting off the X server from the outside world resulting in freezing the openQA test.

And the moral of the story is: probably none. But it highlights again that the automated test setup can have unexpected feedback on the test itself. Luckily in this case, as the issue would not have been noticed otherwise.

Computer, Enlarge the Device Graph

The partitioner module has a graphical view to help you see the relations in more complex storage setups:

If you turn the mouse scroll wheel up or down, we will zoom the view in or out. Now the direction matches the behavior in web browsers and online maps, previously we had it the wrong way around.

Update: during proofreading, a team mate told me: "A device graph? That’s not a device graph. THAT’s a device graph:"

Highlights of YaST Development Sprint 84

September 16th, 2019 by

The YaST Team finished yet another development sprint last week and we want to take the opportunity to let you all glance over the engine room to see what’s going on.

Today we will confess an uncomfortable truth about how we manage the Qt user interface, will show you how we organize our work (or at least, how we try to keep the administrative part of that under control) and will give you a sneak peak on some upcoming YaST features and improvements.

Let’s go for it!

There Be Dragons: YaST Qt UI Event Handling

The YaST Qt UI is different in the way that it uses Qt. Normal Qt applications are centered around a short main program that after initializing widgets passes control to the Qt event loop. Not so YaST: it is primarily an interpreter for the scripts (today in Ruby, in former times in YCP) that are executed for the business logic. Those scripts, among other things, also create and destroy widget trees. But the control flow is in the script, not in a Qt event loop. So YaST uses different execution threads to handle both sides: graphic’s system events for Qt widgets and the control flow from the scripts.

This was always quite nonstandard, and we always needed to do weird things to make it happen. We always kind of misused Qt to hammer it into shape for that. And we always feared that it might break with the next Qt release, and that we might have a hard time to make it work again.

This time has now come with bug#1139967, but we were lucky enough to find a Qt call to bring it back to life; a QEventLoop::wakeUp() call fixed it. We don’t quite know (yet) why, though. Any hint, anyone?.

Should we even tell you that? Well, we think you deserve to know. After all, it worked well for about 20 years (!)… and now it’s working again.

The Refactoring of YaST Network Keeps Going

What is still not working that fine is the revamped network management. We have been working on it during the latest sprint, but it will take at least another one before it’s stable enough to be submitted to openSUSE Tumbleweed.

On which parts have we be working during the this sprint? Glad you asked! 😉 We are cleaning the current mess in wireless configuration. Soon that part will be more intuitive and consistent with other types of network. We are also making sure we propose meaningful defaults for the new cards added to the network configuration (all types of cards, not only wireless). The functionality to configure udev in order to enjoy stable names for the network interfaces has also received some love. The new version is more stable and flexible. And last but not least, we are improving the device activation in s390 systems for it to be more straightforward in the code and more clear in the user interface.

If everything goes as planned, by the end of the next sprint we will be ready to submit the improved YaST Network to Tumbleweed. That will be the right time for a dedicated blog post with screenshots and further explanations of all the changes.

Enhancing the Partitioner Experience with Encrypted Devices

And talking about ongoing work, we are currently working to broaden the set of technologies and use-cases the Partitioner supports when it comes to data encryption. As with the network area, the big headlines in that regard will have to wait for future blog posts. But if you look close enough to the user interface of the Partitioner available in Tumbleweed you can start spotting some small changes that anticipate the upcoming new features.

The first change is very subtle. When visualizing the details of an encrypted device, next to the previously existing “Encrypted: Yes” text you will now be able to see the concrete type of encryption. For all devices encrypted using YaST, that type will always be LUKS1 since that’s the only format that YaST has supported… so far. 😉

Partitioner: show the type of encryption

Some other small changes are visible when editing an encrypted device. If such a device was not originally encrypted in the system, nothing changes apart from minor adjustments in the labels. The user simply sees a form with an empty field to enter the password.

Encrypting a plain device

When editing for a second time a device that was already marked for encryption during the current execution of the Partitioner, the form is already prefilled with the password entered before. In the past, the previous encryption layer was ditched (so it’s password and other arguments were forgotten) and the user had to define the encryption again from scratch. That will become even more relevant soon, when the form for encryption becomes more than just a password field. Stay tuned for news in that regard.

Editing an encrypted device

Moreover, when editing a device that is already encrypted in the system, an option is offered to just use the existing encryption layer instead of replacing it with a (likely more limited) encryption created by the Partitioner.

Keeping the previous encryption layer

Apart from opening the door for more powerful and relevant changes in the area of encryption, these changes represent an important usability improvement by themselves.

Tidying up the YaST Team’s Trello Board

As you can see in this report and in all the previous ones, the YaST Team works constantly on many different areas like installation, network management, storage technologies… you name it. We use Trello to organize all that work. For each bug in Bugzilla or feature in Jira there is a corresponding Trello card. As it happens, sometimes when a bug is closed its Trello card is forgotten to be updated.

A check with ytrello revealed that, out of a total of 900-something cards, about 500 were outdated and could be closed. More than the half! Why so many?

We found that quite a number of these cards were open cards in closed (archived) lists. So when you archive a list, don’t forget to archive its cards before. We have just learned that Trello does not do this automatically. That’s exactly why there’s a menu item Archive All Cards in This List... besides Archive This List in the Trello user interface.

Back to work!

This has been a summer of promises on our side. We told you we are working to improve our user interface library (libYUI), revamping the code to manage the network configuration, extending the support for encryption… which means we have a lot work to be finished.

So let us go back to work while you do your part – having a lot of fun!

Highlights of YaST Development Sprint 83

August 30th, 2019 by

The summer is almost gone but, looking back, it has been pretty productive from the YaST perspective. We have fixed a lot of bugs, introduced quite interesting features to the storage layer and the network module refactoring continues to progress (more or less) as planned.

So it is time for another sprint report. During the last two weeks, we have been basically busy squashing bugs and trying to get the network module as feature-complete as possible. But, after all, we have had also some time to improve our infrastructure and organize for the future.

YaST2 Network Refactoring Status

Although we have been working hard, we have not said a word about the yast2-network refactoring progress since the end of July, when we merged part of the changes into yast2-network 4.2.9 and pushed it to Tumbleweed. That version included quite a lot of internal changes related to the user interface and a few bits of the new data model, especially regarding routing and DNS handling.

However, things have changed a lot since then, so we would like you to give you an overview of the current situation. Probably, the most remarkable achievement is that the development version is able to read and write the configuration using the new data model. OK, it is not perfect and does not cover all the use cases, but we are heading in the right direction.

In the screencast below you can see it in action, reading and writing the configuration of an interface. The demo includes handling aliases too, which is done way better than the currently released versions.

YaST2 Network New Data Model in Action

Moreover, we had brought back support for many types of devices (VLAN, InfiniBand, qeth, TAP, TUN, etc.), improved the WiFi set-up workflow and reimplemented the support for renaming devices.

Now, during the current sprint, we are focused on taking this new implementation to a usable state so we can release the current work as soon as possible and get some feedback from you.

Finally, if you like numbers, we can give you a few. Since our last update, we have merged 34 pull requests and have increased the unit test coverage from 44% in openSUSE Leap 15.0/SUSE Linux Enterprise SP1 to around 64%. The new version is composed of 31.702 (physical) lines of code scattered through 231 files (around 137 lines per file) vs 22.542 in 70 files of the old one (more than 300 lines per file). And these numbers will get better as we continue to replace the old code 🙂

Missing Packages in Leap

It turned out that some YaST packages were not updated in Leap 15.1. The problem is that, normally, the YaST packages are submitted to the SLE15 product and they are automatically mirrored to the Leap 15 distribution via the build service bots. So we do not need to specially handle the package updates for Leap.

However, there are few packages which are not included in the SUSE Linux Enteprise product line, but are included in openSUSE Leap. Obviously these packages cannot be updated automatically from SUSE Linux Enterprise because they are not present there. In this case Leap contained the old package versions from the initial 15.0 release.

In order to fix this issue, we manually submitted the latest packages to the Leap 15.2 distribution. To avoid this problem in the future we asked the Leap maintainers to add the Leap specific packages to a check list so they are verified before the next release. Of course, if you see any outdated YaST package in Leap you can still open a bug report. 😉

Just for reference, the affected packages are: yast2-alternatives, yast2-slp-server, yast2-docker and skelcd-control-openSUSE (the content is only present on the installation medium, it’s not released as an RPM).

Let’s use all disks!

As you may remember, three sprints ago we added some extra configuration options to make the storage guided proposal able to deal with the SUSE Manager approach. We even wrote a dedicated blog post about it!

Despite offering the new options in the Guided Setup, we tried to keep the default initial behavior of the installer consistent with other (open)SUSE products. So the installer initially tried to install the whole system in a single disk, unless that was impossible or it was told by the user to expand on several disks.

But the SUSE Manager folks found that to be contrary to the new ideas introduced in their Guided Setup. According to their feedback, in this case remaining consistent with other (open)SUSE product was not reducing the confusion, but rather increasing it. SUSE Manager should try from the very beginning to expand the product as much as possible among all available disks.

For that reason, during this sprint we introduced the first improvement (a.k.a. another configuration option), so now it is possible to tell whether the initial proposal should try to use multiple disks as first try.

Bootloader and Small MBR Gaps

We received a bug report because a system was not able to boot after installation. In this case, the user decided to use Btrfs and placed the root file system in a logical partition. In theory, this scenario should work but, unfortunately, the MBR gap was too small to embed the Grub2 bootloader code.

At first sight, this problem could be solved by asking YaST to install the bootloader into the logical partition and the generic boot code in the MBR. But this will only work if you set the logical partition as the active one. Sadly, some BIOSes could insist on having a primary partition as the active one.

But don’t worry, we have good news. Grub2 maintainers took care of this problem. In case the MBR gap is too small, Grub2 will automatically fall-back to the Btrfs partition. That’s all. And what does it mean for YaST? Well, thanks to this fix, YaST will simply work out of the box and your system will be bootable again. But not so fast! You still have to wait a little bit more to have these Grub2 improvements available in a Tumbleweed installer.

Handling Empty Comment Lines in NTP Configuration

AutoYaST supports defining an specific NTP configuration to be applied during the installation and it relies in Augeas to read/write the ntp.conf file. But it seems that Augeas has some problems when it tries to write comments with empty lines, as you can see in bug 1142026. The solution was to adapt YaST to filter out empty comment lines before saving the configuration file, working around the Augeas problem.

Error Resizing Some Partitions

Typically, an MS-DOS partition table reserves its first MiB for the MBR gap, so the partitions normally start after that point. But it is possible, especially in partitions for old Windows systems, that it starts before that first MiB. In that case, if we try to resize that partition (e.g., by using the Expert Partitioner), YaST crashes due to an error when calculating the resize information. Fortunately, this problem is gone now, and you will be able to resize this kind of partitions as well.

Side Effects of Keyboard Layouts Unification

During the sprint 81, the openSUSE and SUSE Linux Enterprise console keyboard layouts were unified after some minor changes. One of those changes was to stop using the, in appearance, useless keymaps symlinks for Arabic and Cambodian. But they were there for a reason: are being used by YaST to correctly adapt the keyboard in the X11 environment. Just visit the pull request if you prefer to scare yourself want to dive in more technical details.

Fortunately for the users of those keyboards, we realized about this problem before the upcoming SLE-15-SP2 was released 🙂 And, it’s fixed.

House Keeping Tasks

As part of our development duties for this sprint, we invested quite some time in reviewing and updating our continuous integration (CI) set up. Apart from using Travis CI for pull requests, we rely on Jenkins to run the tests and submit the code to the appropriate projects in the Open Build Service instances.

Then, when the development of a new version starts or when the product is about to be released, we need to adjust the configuration. Just in case you are wondering, we do not do this work by hand anymore and we use Salt and Jenkins Job Builder to handle this configuration.

Closing Thoughts

During the next sprint (actually, the current one) we are working in three different areas, apart from squashing bugs: improving encryption support in the storage layer, adding some features to the installer (repo-less installer, support for reading product licenses from a tarball, etc.) and, of course, refactoring the network code. Obviously, we will give you all sort of details in our next sprint report.

Highlights of YaST Development Sprint 82

August 14th, 2019 by

July and August are very sunny months in Europe… and chameleons like sun. That’s why most YaST developers run away from their keyboards during this period to enjoy vacations. Of course, that has an impact in the development speed of YaST and, as a consequence, in the length of the YaST Team blog posts.

But don’t worry much, we still have enough information to keep you entertained for a few minutes if you want to dive with us into our summer activities that includes:

  • Enhancing the development documentation
  • Extending AutoYaST capabilities regarding Bcache
  • Lots of small fixes and improvements

AutoYaST and Bcache – Broader Powers

Bcache technology made its debut in YaST several sprints ago. You can use the Expert Partitioner to create your Bcache devices and improve the performance of your slow disks. We even published a dedicated blog post with all details about it.

Apart of the Expert Partitioner, AutoYaST was also extended to support Bcache devices. And this time, we are pleased to announce that … we have fixed our first Bcache bug!

Actually, there were two different bugs in the AutoYaST side. First, the auto-installation failed when you tried to create a Bcache device without a caching set. On the other hand, it was not possible to create a Bcache with an LVM Logical Volume as backing device. Both bugs are gone, and now AutoYaST supports those scenarios perfectly.

Configuring Bcache and LVM with AutoYaST

But Bcache is a quite young technology and it is not free of bugs. In fact, it fails when the backing device is an LVM Logical Volume and you try to set the cache mode. We have already reported a bug to the Bcache crew and (as you can see in the bug report) a patch is already been tested.

Enhancing Our Development Documentation

This sprint we also touched our development documentation, specifically we documented our process for creating the maintenance branches for the released products. The new branching documentation describes not only how to actually create the branches but also how to adapt all the infrastructure around (like Jenkins or Travis) which requires special knowledge.

We will see how much the documentation is helpful next time when somebody has to do the branching process for the next release. 😉

Working for a better world YaST

We do our best to write code free of bugs… but some bugs are smarter than us and they manage to survive and reproduce. Fortunately we used this sprint to do some hunting.

Those are only some examples of the kind of bugs we have fought during this sprint. But checking bug reports has also made us think in the future…

LibYUI in 21st Century

We fixed a bug related to how the focus was managed in text mode after changing any setting via the hyperlinks available in the installation summary.

Installation summary in text mode

The implemented solution is actually not perfect, it’s just the better we can do with our set of widgets. And that was yet another example of such problem – LibYUI is an awesome library that allows us to create interfaces that work in both graphic and text modes, but it has basically not evolved for more than a decade… and it’s time to fix that!

So we have been discussing how to organize our time in the close future to leave some room for innovation and renovation regarding LibYUI and the YaST UI in general. Stay tuned for more news.

August is still not over

The YaST Team will keep working during the rest of the summer sharpening our Linux Swiss army knife. But half of the team is still on vacation or starting their vacation now. So most likely our next report will be here in two weeks and it will also be a light read.

Meanwhile, don’t forget to have a lot of fun!

Highlights of YaST Development Sprint 81

July 29th, 2019 by

Unifying the Console Keyboard Layouts for SLE and openSUSE

The way of managing internationalization in Linux systems has changed through the years, as well as the technologies used to represent the different alphabets and characters used in every language. YaST tries to offer a centralized way of managing the system-wide settings in that regard. An apparently simple action like changing the language in the YaST interface implies many aspects like setting the font and the keyboard map to be used in the text-based consoles, doing the same for the graphical X11 environment and keeping those fonts and keyboard maps in sync, ensuring the compatibility between all the pieces.

For that purpose, YaST maintains a list with all the correspondences between keyboard layouts and its corresponding "keymap" files living under /usr/share/kbd/keymaps. Some time ago the content of that list diverged between openSUSE and SLE-based products. During this sprint we took the opportunity to analyze the situation and try to unify criteria in that regard.

We analyzed the status and origin of all the keymap files used in both families of distributions (you can see a rather comprehensive research starting in comment #18 of bug#1124921) and we came to the conclusions that:

  • The openSUSE list needed some minor adjustments.
  • Leaving that aside, the keymaps used in openSUSE were in general a better option because they are more modern and aligned with current upstream development.

So we decided to unify all systems to adopt the openSUSE approach. That will have basically no impact for our openSUSE users but may have some implications for users installing the upcoming SLE-15-SP2. In any case, we hope that change will be for the better in most cases. Time will tell.

Exporting User Defined Repositories to AutoYaST Configuration File.

With the call yast clone_system an AutoYaST configuration file will be generated which reflects the state of the running system. Up to now only SUSE Add-Ons have been defined in the AutoYaST configration module. Now also user defined repositories will be exported in an own subsection <add_on_others> of the <add-on> section.

<add-on>
  <add_on_others config:type="list">
    <listentry>
      <alias>yast_head</alias>
      <media_url>https://download.opensuse.org/repositories/YaST:/Head/openSUSE_Leap_15.1/</media_url>
      <name>Yast head</name>
      <priority config:type="integer">99</priority>
      <product_dir>/</product_dir>
    </listentry>
  </add_on_others>
  <add_on_products config:type="list">
    <listentry>
      <media_url>dvd:/?devices=/dev/sr1</media_url>
      <product>sle-module-desktop-applications</product>
      <product_dir>/Module-Desktop-Applications</product_dir>
    </listentry>
    <listentry>
      <media_url>dvd:/?devices=/dev/sr1</media_url>
      <product>sle-module-basesystem</product>
      <product_dir>/Module-Basesystem</product_dir>
    </listentry>
  </add_on_products>
</add-on>

The format of the <add_on_others> section is the same as the <add_on_products> section.

Better Handling of Broken Bootloader Setups during Upgrade

With the current versions of SLE and openSUSE, using the installation media to upgrade a system which contains a badly broken GRUB2 configuration (e.g. contains references to udev links that do not longer exist) can result in an ugly internal error during the process.

The first possible problem could arise in the summary screen. Like shown in this screenshot.

If the error didn’t pop-up or if the user managed to recover from it, it was possible to reach the final phase of the upgrade process. But then the same internal error could still pop up in a different place:

Those errors will be fixed in the upcoming releases of SLE-12-SP5 and SLE-15-SP2 and, of course, in the corresponding openSUSE Leap version and in Tumbleweed. Now if such a broken setup is detected in the summary screen, a proper warning is displayed, including the technical details and a tip on what to do to fix the problem.

The user can ignore the problem or click on "booting" to fix it. In the latter case, the usual pop-up with instructions will appear.

If the final stage of the upgrade process is reached without fixing the error, the wild internal error is now replaced by an informative message that does not interrupt the process.

Hopefully most of our users will never see these improvements. But users with a broken system will likely appreciate the extra guidance.

Old Storage, New Features

If you are an usual reader of this blog, most likely you already know that YaST has a completely re-implemented Storage stack (a.k.a. storage-ng). That new storage code did its debut with the SLE 15 (and openSUSE Leap 15.0) family. And thanks to this revamped code, our beloved users can enjoy today some new great features in YaST like Bcache, partitionable Software RAIDs or multi-device Btrfs file system (just to mention a few examples). But SLE 12 (openSUSE 42) products are still alive and getting improvements with every maintenance update! Of course, the old Storage stack is not an exception, and now on a new installation scenario is supported.

Thanks to a bug report, we realized that Snapper could not be configured in some cases. More specifically, the reporter was trying to install with AutoYaST over a directly formatted Software RAID by using Btrfs for root and enabling snapper. The installation was perfectly performed, but it turned out that snapper was not correctly enabled in the installed system. After having a deeper look into the problem, we discovered that this was not a bug exactly but a completely missing feature. But no problems, YaST got down to work and now it is nicely supported.