Author Archive for Stefan Schubert
Tuesday, December 15th, 2009 by Stefan Schubert
After releasing WebYaST 1.0 last week we have had a look to the status module again and have come to the conclusion that we can do it better.
The current version looks more like a medical monitoring system that no one understand:

Technical background
The system data will be collected by a service called collectd (www.collectd.org). This data will be stored in a rrd-database which is located in
/var/lib/collectd/<system-name>/[cpu-0|cpu-1|df|interface|load|memory|....]
An own file/database will for each value will be generated.
The upper screen shot shows that an own graphic will be shown for each value. This is not really user friendly. We would like to show only values which provides “really” interesting information for the sysadmin or user. These values should also be grouped in order to reduce the amount of graphs.
Another lack of information is the labeling of the graphs. There is no description what the values mean and in which period they have been evaluated.
The aim
would be to give the user a nice overview about the system status. Additional, there should be an alarm system available if system values are exceeded. E.g. there should be sent an email to the system administrator if no disk space is available anymore.
The Administrator should also be able to configure “his” needed system values in a nice way.
Suggestion for configuration

There are three parts:
- General
General setting like period time of shown data, email address in the case of occurred errors and the color of displayed limits. - Graphics
Defining graphs with- labels
- scales
- flag for cumulate values
This means that the values in the graph are added. E.g. the component df of collectd returns two values of a partition (free, used). These values will be cumulated in the graph like this:

- Enable Values/Limits
- Defining which data of collectd will be shown in the graphics described above. This enable us to group data in one graph, defining color and label of each collectd value:

- Defining limits and send an email if the value is overstepped longer than the defined period (Alarm after (min.))
- Defining which data of collectd will be shown in the graphics described above. This enable us to group data in one graph, defining color and label of each collectd value:
The Result
should be an amount of view graphs which include interesting data only. These values are checked periodically and an email will be sent if they exceed a defined limit.
I am asking for
your opinion about:
- Do you know a much more fancy way for displaying system status data ?
- Which kind of Data would be interesting for you (CPU, memory, disk-space,….)?
- When and for which kind of data would you like to get an email if limits have been exceeded?
So, before changing this module we would like to ask you what you would like to see.
Thanks in advance.
New YaST-Web released 1.0.1
Wednesday, April 1st, 2009 by Stefan SchubertWe have released a new version of Web-YaST with following changes:
- Added translation support on the client side.
- Added ruby-gettext
- Split off ruby-rpam and ruby-polkit in single packages.
- Switch off IPv6 in lighttpd cause it has produced some undefined errors. (esp. on 64bit)
- Added package dependencies concerning rails. The last few weeks have shown that RAILS versions are not really compatible. So many problems have been happened due different RAILS versions on the systems where YaST-Web has been installed. Please use RAILS 2.1
- Cleanup code.
The newest packages can be found here:
https://build.opensuse.org/project/show?project=home:schubi2
Or
https://build.opensuse.org/project/show?project=YaST:Web
It would be nice to get some feedback. Bugzilla would be a nice option
Thank you !
YaST WEB
Tuesday, February 3rd, 2009 by Stefan SchubertAim
First of all we want to provide an general web based interface with the
functionality which is already provided by the YaST command line interface.
This API is based on the REST (Representational state transfer) architecture. This is a
simple interface which transmits domain-specific data over HTTP.
Please have a look to
http://en.wikipedia.org/wiki/Representational_State_Transfer
for more information about REST.
The second aim is to provide a YaST Web UI which can be used by every
web browser.
The current state of the project is an existing YaST-Webservice on the
host side which provides the REST based interface.
On the client side we have the concerning YaST-Webclient which can be
used be any web browser.
YaST-Webservice and YaST-Webclient are running as a webserver
(currently lighttpd) on different or even the same computer.
So the aim is to configure a host via the internet in a simple and
safety way.
How does it work ?

The YaST Webclient communicate via HTTP(s) with the YaST Webservice. The
user has to authenticate ( username, password ) to the host via PAM
(Pluggable Authentication Modules) which is available on every linux system.
The YaST Webclient sends requests ( e.g. create a user, install patch) to
the YaST Webservice. This service checks if the user has the right to
execute this request via PolicyKit. For each kind of request there is
PolicyKit rule defined. These rights has to be granted to the concerning user.
After permission check the request will be send via DBUS to the SCR agent of
YaST. The return value will be given back to YaST-Webclient in XML or JSON
format.
Patches will be handled by PackageKit. These requests will also be sent from
the YaST Webservice to PackageKit via DBUS.
How to get it ?
Have a look the openSUSE buildservice project
YaST Webservice (home:schubi2)
There are all needed packages for version openSuSE 11.1 and above.
As some additional packages (e.g. lighttpd) are needed which are not on openSuSE 11.1 you should add a
repositories ( e.g. factory ) in order to provide these packages.
The simplest way for installation would be to use zypper:
zypper in yast2-core-2*.rpm
zypper in ruby-dbus-*.rpm
zypper in yast2-webservice-*.rpm
zypper in yast2-webclient-*.rpm
How to use the YaST-Webservice
After you have installed these packages you can start the YaST-Webservice-Server with
rcyastws start
The server is running as “localhost:8080″ with which you can connect with a web browser:
http://localhost:8080

This “pure” web page shows the available modules which can be used via the REST interface.
This REST API is described under
http://localhost:8080/doc_interface.html
Additional configuration stuff like
- setup Hostname and Port
- setup HTTPS connection
- granting permissions for an single user
- AVAHI support
can be found here:
http://localhost:8080/doc_config.html
How to use the YaST-Webclient
After you have started the YaST-Webservice-Server you also can start the YaST-Webclient:
rcyastwc start
Now you can use any browser and connect with http://<name of your computer> to your
computer.
The default rights of the YaST Webservice are set to root only. So you can login with the root password
of that machine.
Following features are implemented:
- setting languages
- setting system time
- setting user permissions
- installing patches
- managing local users
- export user SSH-keys
- starting,stopping,status,… of services
- configuration of ntp server
Have a look to the following screen shot it order to give an overview how it looks like:



Known Bugs
-The first call of an menue entry will be slow cause an additional process will be started.
The second one should be much more faster ![]()
-Permissions will sometime not be shown correctly (just click “search” again) Bug 470645
Showing package dependencies
Friday, June 27th, 2008 by Stefan SchubertIn order to give an answer about “Why this package will be installed and who needs it?” I have added a new Dialog in the QT single package selector:
Select one item (pattern, package) in the single selection frame, use the right mouse button and select “Show solver information”. A solverrun will be made for this item and the result will be shown with this dialog.
- Black arrow : This item will be required by….
- Green arrow: This item will be recommended by…
- Green boxes: This package is already installed
- Grey boxes: This package will be installed
- Blue boxes: Patterns
You can navigate through the tree via the overview frame:
After you have selected one item in the tree you can see more information about:
e.G. this item will install two further patterns due to the shown dependencies.
In order to decrease the complexity of the tree you can blind out:
- already installed packages
- recommended packages/patterns
So you will get a shrinked tree:
Technical Background:
This is a simple Qt Dialog widget which can be used in other programs too. ( Package libqdialogsolver1)
YaST uses this widget as a YaST plugin. So if this package is not available you will get a popup in single selection only.



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