Posts Tagged ‘custom’

How to Remove / Add SuSE Linux start service command

Thursday, July 2nd, 2015

opensuse-remove-add-new-service-geeko-suse-linux-mini-logo
If you happen to administer SUSE LINUX Enterprise Server 9 (x86_64) and you need to add or remove already existing /etc/init.d script or custom created Apache / Tomcat .. etc. service and you're already familiar with Fedora's / RHEL chkconfig, then the good news chkconfig is also available on SuSE and you can use in same way chkconfig to start / stop / enable / disable boot time services.

To list all available boot time init.d services use:
 

suse-linux:/etc # chkconfig –list

 

SuSEfirewall2_final       0:off  1:off  2:off  3:off  4:off  5:off  6:off
SuSEfirewall2_init        0:off  1:off  2:off  3:off  4:off  5:off  6:off
SuSEfirewall2_setup       0:off  1:off  2:off  3:off  4:off  5:off  6:off
Tivoli_lcfd1.bkp          0:off  1:off  2:off  3:off  4:off  5:off  6:off
activate_web_all          0:off  1:off  2:off  3:on   4:off  5:on   6:off
alsasound                 0:off  1:off  2:on   3:on   4:off  5:on   6:off
apache2                   0:off  1:off  2:off  3:off  4:off  5:off  6:off
apache2-eis               0:off  1:off  2:off  3:on   4:off  5:off  6:off
atd                       0:off  1:off  2:off  3:off  4:off  5:off  6:off
audit                     0:off  1:off  2:off  3:off  4:off  5:off  6:off
autofs                    0:off  1:off  2:off  3:off  4:off  5:off  6:off
autoyast                  0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.clock                0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.crypto               0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.device-mapper        0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.evms                 0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.idedma               0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.ipconfig             0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.isapnp               0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.klog                 0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.ldconfig             0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.loadmodules          0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.localfs              0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.localnet             0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.lvm                  0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.md                   0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.multipath            0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.proc                 0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.restore_permissions  0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.rootfsck             0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.sched                0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.scpm                 0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.scsidev              0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.shm                  0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.swap                 0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.sysctl               0:off  1:off  2:off  3:off  4:off  5:off  6:off
boot.udev                 0:off  1:off  2:off  3:off  4:off  5:off  6:off
coldplug                  0:off  1:on   2:on   3:on   4:off  5:on   6:off

 

To then stop the service:
 

suse-linux:/etc # chkconfig gtiweb off


If you prefer to do it the SuSE way and learn a bit more on SuSE boot time process check out:

 

suse-linux:/etc # man insserv


Removing already existing SuSE start-up script from init.d start up with insserv is done with:

suse-linux:/etc # cd /etc/init.d/
suse-linux:etc/init.d # insserv -r gtiweb
insserv: script ipmi.hp: service ipmidrv already provided!
insserv: script boot.multipath.2008-10-29: service boot.multipath already provided!


To install a new custom written and placed into /etc/inti.d/ on SuSE's server boot time with insserv:

 

suse-linux:/etc/init.d/ # insserv your_custom_script_name

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Disabling PHP system(); and exec(); functions to raise up Apache security on Debian GNU / Linux

Wednesday, July 18th, 2012

Disabling PHP system(); and exec(); functions to raise up Apache security on Debian Gnu / Linux

At security critical hosts running Apache + PHP based sites it is recommended functions like:

system();
exec();shell_exec();.....

to be disabled. The reason is to mainly harden against script kiddies who might exploit your site/s and upload some shitty SK tool like PHP WebShell, PHP Shell and the probably thousands of “hacker” variations that exist nowdays.

In latest Debian stable Squeeze, suhosinadvanced protection module for php5 is being installed and enabled in Apache (by default).
Simply disabling a number of functions using suhosin, could prevent multiple of future headaches and hours of pondering on who 0wn3d your server ….

Disabling the basic PHP system(); and other similar functions which allows shell spawn is not always possible, since some websites or CMS platforms depends on them for proper runnig, anyways whether it is possible disabling ’em is a must.
There are two ways to disable system(); functions; One is through using /etc/php5/apache2/conf.d/suhosin.ini and 2nd by adding a list of functions that has to be disabled directly in Website Virtualhost file or in apache2.conf (/etc/apache2/apache2.conf;
For people hosting multiple virtualhost websites on the same server using the custom domain Virtualhost method is probably better, since on a global scale the functions could be enabled if some of the websites hosted on the server requires exec(); to work OK. In any case using /etc/php5/apache2/conf.d/suhosin.ini to disable system(); functions in PHP is less messy …

1. Disabling PHP system(); fuctions through /etc/apache2/apache2.conf and custom site Vhosts

Place somewhere (I prefer near the end of config);;;


php_admin_flag safe_mode on
php_admin_value disable_functions "system, exec, shell_exec, passthru , ini_alter, dl, pfsockopen, openlog, syslog, readlink, symlink, link, leak, fsockopen, popen, escapeshellcmd, apache_child_terminate apache_get_modules, apache_get_version, apache_getenv, apache_note,apache_setenv,virtual"

Disabling it for custom virtualhost is done by simply adding above Apache directvies (before the closing tag in /etc/apache2/sites-enabled/custom-vhost.com

2. Disabling PHP system();, exec(); shell spawn with suhosin.ini

In /etc/php5/apache2/conf.d/suhosin.ini add;;

suhosin.executor.func.blacklist =system, exec, shell_exec, passthru, ini_alter, dl,
pfsockopen, openlog, syslog, readlink, symlink, link, leak, fsockopen, popen,
escapeshellcmd, apache_child_terminate apache_get_modules, apache_get_version,
apache_getenv, apache_note,apache_setenv,virtual

To do it directly via shell issue;;;

server: conf.d/# cd /etc/php5/apache2/conf.d/
server: conf.d# echo 'suhosin.executor.func.blacklist =system, exec, shell_exec, passthru, ini_alter, dl,' >> suhosin.ini
server: conf.d# echo 'pfsockopen, openlog, syslog, readlink, symlink, link, leak, fsockopen, popen,' >> suhosin.ini
server: conf.d# echo escapeshellcmd, apache_child_terminate apache_get_modules, apache_get_version,' >> suhosin.ini
server: conf.d# echo 'apache_getenv, apache_note,apache_setenv,virtual' >> suhosin.ini

Then to re-load the memory loaded Apache libphp library an Apache restart is necessary;

server: conf.d# /etc/init.d/apache2 restart
Restarting web server: apache2 ... waiting .
server: conf.d#

Tadam, this should be quite a good security against annoying automated script attacks. Cheers 😉

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Three Ways to Reduce Addiction to Mobile Phone ( GSM ) use

Wednesday, June 27th, 2012

Mobile Phone Caricature Reduce Mobile Addiction / 3 ways to reduce mobile phone addiction / Use your Mobile less

1.: Don't use a ring tone or use a short landline phone ringtone on incoming calls

In the past, we all had a local stand line phones, most of the landline phones rung using a very specific ring sound which was almost identical on all phones around the world. This ringing tone used was following some telephone standards. The result was everyone could distinguish a ringing phone in a room or closed space and tell for sure, this sound is generated by a phone. Nowdays with the boom of cellular phone ringtones, there is almost noone who uses a standard old-fashioned telephone ringtone as a ring melody.

The consequence of this is in our minds we start loosing the boundary between whether communicating on the phone or communicating without it.
In younger people this boundary between phone line and a physical communication is more evident than in adults (as youngsters has grown in society where mobile was used everywhere). The implication of this is more and more people are starting to perceive mobile communication as so natural as the person to person communication. Spending big part of the day talking over the phone mostly senseless things, not being consciously aware that this is done due to a heavy phone addiction and repeating behaviour trait stored sub-consciously.

Today everyone chooses a custom mobile phone ringtone melody (popular or impopular) song and sets it up to be a standard incoming call signal. As you can guess there are consequences on the mind, as the ringtone set is heard ten times or more a day during each and every phone call. The result is just like with alcoholics or drug addicts, the more you take from a certain "good" the more attached you become to it. Hence the more we listen to a certain song chunk daily on incoming calls, the sub-conscious becomes dependent on hearing this sound at least a number of times daily. If a day passes without no-one calling us and we don't hear the ringtone indicating a call the sub-conscious stored dependency starts popping up and we could start feeling lonely and we feel like calling someone (and we often do). Obviously this is dependency and even if someone might argue me this is a severe addiction which as every other addiction could be very dangerous and hard to fight.

As I prior said due to the fact that the phone use dependency is built in our minds starting with the phone ring melody, we can reduce this dependency by switching off the phone ringtone completely or at least changing it to a unique beep which is not likely to be heard or seen somewhere in your surrounding environment.

By setting the ringtone to some popular song we see on (TV, Radio or Internet on daily basis) this might become a trigger for us to associate hearing this sound with talking on the phone and hence make you increase the time you spend on the phone ,,, so be careful ,,,,

2.:: Stop Mobile Beeps and sounds on menu navigation

All new mobiles sold on the market are configured to have buzzling sounds on events and various beeps on keypad lock / unlock and menu navigation.
This sounds are there mostly to make you more alert and concentrated on using your mobile and often as a consequence whether one uses his mobile his awareness is comletely taken by the phone screen (you're totally "absorbed" by the phone use).
Besides designed to alert you the Managers and CEO's who decided to have a heavy beep sounds on mobiles made it having probably something else on mind? The beeps on keypad navigation makes the user emotionally and sub-consciously attached to the Cell Phone. The idea here is like in popular music streamed on radios and TVs and mostly everywhere …. The more you listen to a song, the higher the mind trait it leaves in you, so later when one hears a music pattern or a whole song, which he / she listened already thousands of times this brings back "good" old memories. It is very simple actually our minds are constructed in a way that the mor certain "information" is heard / saw / smell the bigger the mind influence this leaves on us. Back to the mobile sounds, the more you use the mobile phone with turned on sounds, the more addicted and mind stucked the beep and melodies during use of the cell phone becomes in the mind. For example many people take a look at their mobile automatically (without being consciously aware) and do the activity of (unlock) and (lock) the phone screen not knowing they do it automatic. More or less we all do such an auto-mated learned behaviour because of the subconscious dependency that is built in our minds. Whether we lock and unlock the mobile phone almost robotically, we do it because our sub-conscious mind plays a trick on us and "force" us to do a previous learned activity (association in our mind with the unlock / lock beep sound).

3.::: Use your mobile in different ways

Any modern mobile is quite advanced in functionality and there is more than one way to initiate a phone call. E.g. the mobile has a shortcut buttons assigned to do quick phone calls, quickly evoke SMS menu etc.
Learn them and occasionally use the shortcut buttons instead of the menu navigation. Our minds like changing patterns and doing things different.

Even if you have no chance to do a things via a certain menu, you can always change the position of the phone screen to different distance to eyesight 🙂 You can for example type on the keypad following the menu steps by watching from left or right eye periphery or you can use the menus with your phone screen turned backwards 🙂 If you're used to type on the keypad or touch screen with right hand try doing it with the left hand 🙂

This will take time but the fun worths it. Plus the most valuable thing in using the mobile in different ways each time is there is no specific inflicting pattern associated in your mind and hence the depepdency set in your sub-conscious mind on phone use is lesser.
Actually there are too many various "hacks" one could come up with on how to use mobile as differently as possible. It is up to your imagination. Though using the mobile "each-time-different" can be sometimes more time-consuming it surely makes your phone use amusing.

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How to mount ISO image files in Graphical Environment (GUI) on Ubuntu and Debian GNU/Linux

Saturday, January 14th, 2012

Mounting ISO files in Linux is easy with mount cmd, however remembering the exact command one has to issue is a hard task because mounting ISO files is not a common task.

Mounting ISO files directly by clicking on the ISO file is very nice, especially for lazy people uninitiated with the command line 😉

Besides that I'm sure many Windows users are curious if there is an equivallent program to DaemonTools for Linux / BSD*?

The answer to this question is YES!
There are two major programs which can be used as a DaemonTools substitute on Linux:

These are FuriousISOMount and AcetoneISO
AcetoneISO is more known and I've used it some long time ago and if I'm correct it used to be one of the first ISO Mount GUI programs for Linux. There is a project called GMount-ISO / (GMountISO) which of the time of writting this article seems to be dead (at least I couldn't find the source code).

Luckily FuriousISOMount and AcetoneISO are pretty easy to install and either one of the two is nowdays existing in most Linux distributions.
Probably the programs can also be easily run on BSD platform also quite easily using bsd linux emulation.
If someone has tried something to mount GUIs in Free/Net/OpenBSD, I'll be interesting to hear how?

1. Mount ISO files GUI in GNOME with Furius ISO Mount

FuriousISOMount is a simple Gtk+ interface to mount -t iso9660 -o loop command.

To start using the program on Debian / Ubuntu install with apt;

debian:~# apt-get install furiusisomount
The following extra packages will be installed:
fuseiso fuseiso9660 libumlib0
The following NEW packages will be installed:
furiusisomount fuseiso fuseiso9660 libumlib0

To access the program in GNOME after install use;

Applications -> Accessories -> Furious ISO Mount

Screenshot ISO Mount Tool Debian GNU/Linux Screenshot
 

When mounting it is important to choose Loop option to mount the iso instead of Fuse

After the program is installed to associate the (.iso) ISO files, to permanently be opened with furiusisomount roll over the .iso file and choose Open With -> Other Application -> (Use a custom command) -> furiusisomount

GNOME Open with menu Debian GNU / Linux

2. Mount ISO Files in KDE Graphical Environment with AcetoneISO

AcetoneISO is build on top of KDE's QT library and isway more feature rich than furiousisomount.
Installing AcetoneISO Ubuntu and Debian is done with:

debian:~# apt-get install acetoneiso
The following NEW packages will be installed:
acetoneiso gnupg-agent gnupg2 libksba8 pinentry-gtk2 pinentry-qt4
0 upgraded, 6 newly installed, 0 to remove and 35 not upgraded.
Need to get 3,963 kB of archives.
After this operation, 8,974 kB of additional disk space will be used.
...

Screenshot Furius ISO Mount Tool Debian GNU/Linux ScreenShot

AcetoneISO supports:
 

  • conversion between different ISO formats
  • burn images to disc
  • split ISO image volumes
  • encrypt images
  • extract password protected files

Complete list of the rich functionality AcetoneISO offers is to be found on http://www.acetoneteam.org/viewpage.php?page_id=6
To start the program via the GNOME menus use;

Applications -> Accessories -> Sound & Video -> AcetoneISO

I personally don't like AcetoneISO as I'm not a KDE user and I see the functionality this program offers as to rich and mostly unnecessery for the simple purpose of mounting an ISO.

3. Mount ISO image files using the mount command

If you're a console guy and still prefer mounting ISO with the mount command instead of using fancy gui stuff use:

# mount -t iso9660 -o loop /home/binary/someiso.iso /home/username/Iso_Directory_Name

 

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The Legend of the Christmas Tree and Why do we put Christmas trees at home in Christmas time? :)

Thursday, January 12th, 2012

Why we put Pine tree / Fir in Christmas origins of Christmas tree / Legends for the Christmas Tree
 

Christmas has just passed away. As a Christian I was curious what is the reason in so many Christian countries, we decorate Pine trees and I did a quick research on the topic. In this small article, I'll present my findings.

Observing the Christmas Pine Tree tradition has been quite ancient and probably according to many sources dates back to the XIIth century.
The first written records of a Christmas tree are of an anonymous Frenchman who visited Strasbourg, Germany in 1601. His description of the decoratd pine tree says like "wafers and golden sugar-twists (Barley sugar), roses cut out of many-colored paper, apples, gold foil and sweets."

Later in the 1800s, the local German Christmas pine tree tradition was spread across America by German emmigrants.
In UK the Pine tree decorating tradition appeard in 1841, where a royalty (Prince Albert) decorated his castle (Winston Castle).

A little later after the Queen Victoria adopted the pine tree, United Kingdom citizens started to decorate pine trees for themselves, folliwng the highly regarded Queen.
Usually the pine tree has historically been decorated with gifts as well as an Bright star is put atop.

One of the Christian interpretations for the Christmas tree is that it represents the same Cross (tree) on which Christ was crucifixed. Then after Christ's resurrection because of (or through that) tree, the humanity received the Lord big spiritual blessings. These blessings are represented by the gifts decorated on the Fir tree. The pine tree itself is in Christianity a reference for the symbol of Salvation that we received came from the Holy Cross, where our saviour was crucified.

The Fir is decorated with lights to represent the joy and the lights of Christmas (that burns in our hearts), the star atop the tree is a reminder of the Star that rised in the East during the night of Christ's birth as we read in the gospels.

Roman Catholic Church Christmas Pine Trees
Decorating Pine trees is commonly observed mostly in Roman Catholic Church and often followed by some protestant denominations and less used in Orthodox Church (though this is changing nowdays).

In Eastern Europe, the Christmas tree appeared quite Legends about the Christmas Fir Treelate and the whole concept was unknown in the Orthodox Christian countries, just until the end of the 19th century.

With the recent severe globalization the pine tree was silenty adopted in almost all parts of the world, including even communist countries and even sometimes in muslim ones.
Enormous Fir Tree in Tarnovo city hill Bulgaria

Unfortunately, the relation between the Fir tree and our Christian faith is little known today and with the years to come it will be less and less associated with Christianity.

Here are few interesting legends which I found explaining, some of the possible roots of the Christmas tree decoration:

Legends about the Christmas Fir Tree

1. Legend of the Pine Tree Saving the Holy Family

When the Holy family was pursued by Herod's soldiers, many plants offered to provide them with shelter.
One such plant was the Pine tree. With Mary too weary to travel any longer, the family stopped at the edge of a forest to rest.
A gnarled old Pine which had grown hollow with the years invited them to rest within its trunk.
Then, it closed its branches down upon them, keeping the family safe until the soldiers had passed.
Upon leaving, the Christ Child blessed the Pine and the imprint of his tiny hand was left forever in the tree's fruit… the Pine cone.
If a cone is cut lengthwise, the hand may still be seen.

2. Pine tree and Easter Legend
 

Pine tree on cones on Easter forms Cross shape

There is a legend that pine trees "know" when it's Easter.
The pine trees start their new growth in the weeks before Easter.
If you look at the tops of the pine trees two weeks before Easter you'll see the yellow shoots.
As the days get closer to Easter Sunday, the tallest shoot will branch off and form a cross.
By the time Easter Sunday comes around, you will see that most of the pine trees will have small yellow crosses on all of the tallest shoots.
This really happens we live where there are lots of pines,
and each year this actually happens, it is amazing to watch,
and the process of the new growth appears as crosses on the ends
of each branch.

I've not personally observed that, but according to people who live in pine tree forest areas this is a fact.

3. Legend about M. Luther and the Pine tree

Martin Luther, founder of the Protestant religion, was taking a stroll through the woods late one night.
The sky was clear and many stars were shining through the branches of the trees,
giving the impression of twinkling lights.
Luther was so captivated and inspired by the beautiful brilliance of the sight
that he cut down a small evergreen and brought it home.
He recreated the stars by placing candles upon the tree's branches to imitate
their radiance and presented it to his children.

This story explains why, the pine tree become so wide spread initially in the "western world", as it gives some connection between the Pine tree and Protestant Christianity.

4. The Children Legend of the Fir Tree (Kids Story)

On the night of the Christ Child's birth, all living creatures, both flora and fauna, traveled to Bethlehem bearing gifts.
The Olive tree, for example, brought its fruit and the Palm tree its dates.
But the little Fir tree had no gift and was so tired that it was unable to resist when the larger trees pushed it into the background and hid it from view.
But then, a nearby Angel took pity and commanded a cluster of stars to descend and rest upon its delicate boughs.
When the Baby Jesus beheld this lovely lighted tree, he smiled and blessed it,
declaring henceforth that Fir trees should always be filled with lights at
Christmastime to please little children.
When Christianity first came to Northern Europe, three personages representing
virtues were dispatched from Heaven to place lights on the original Christmas tree.
These personages were Faith, Hope and Charity.
Their search was long, since they were required to find a tree as high as hope, as great as love and as sweet as charity.
In addition, the tree had to bear the sign of the cross on every bough.
Their search finally ended in the forests of the North where they found the Fir.
Lit by the radiance of the stars, it became the first Christmas tree.
The triangular design of the Fir has also been usedto describe the Holy Trinity of God the Father, The Son and The Holy Spirit.
Eventually, converts began to revere the Fir as God's Tree…as they had once revered the Oak.
By the Twelfth Century it was being hung, upside-down, from ceilings at Christmastime
in Central Europe, as a symbol of Christianity.

5. The Paradise Tree Legend

A very old and delightful European custom centers around decorating a Fir tree with apples and small white wafers which represents the Holy Eucharist.
These wafers were later replaced by small pieces of pastry cut into the shapes of stars, angels, hearts, flowers and bells.
Eventually additional pastries were introduced bearing the shapes of men, birds, roosters and other animals.

During the middle Ages, around the Eleventh century, religious theater was born.
One of the most popular plays …
The German mystery play concerned Adam and Eve and their fall and expulsion from the Garden of Eden, represented by a Fir tree hung with apples.
This tree was symbolic of both the Tree of Life and the Tree of Discernment of Good and Evil, which stood in the center of Paradise.
The play ended with the prophecy of a coming Saviour. For this reason, it was often enacted during Advent.

The one piece of scenery, the "Paradeisbaum" or "Paradise Tree" become a popular object and was often set up in churches.
Eventually it also found its way in private homes and became symbol of the Saviour.
Since the tree was representative not only to Paradise and the fall of man, but also the premise of salvation.
It was hung not merely with apples, but with bread of wafers (Holy Eucharist) and often sweet to represent the sweetness of redemption.
In some areas of Bavaria, fir branches and little trees decorated with lights, apples and tinsel are still called "Paradeis".

According to some other Christian legends, it was a Fir tree that grew as the Tree of Life in the Garden of Eden.
When Eve plucked its fruit, the foliage and flowers shrank to nothing but needles.
Only on the night of Nativity would the Fir tree bloom again a moment marked perhaps by the Christmas tree we Christians use.

Of course these are just legends and as with every legend there is plenty of romantism included.
Nevertheless I consider most legends similar to proverbs contain deep truth and contain truthful facts. Moreover knowing the legends of our forefathers connect us to who and what we are and from antropological point of view is precious knowledge, we should try to sustain and spread to our children.
 

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How to solve ALSA sound problems with old Linux programs and games depending on (OSS)’s /dev/dsp / fix wine games and pulseaudio problems – My few thoughts on OSS and ALSA

Wednesday, January 11th, 2012

 

ALSA OSS Pulseaudio ESD Some fixes workaround to gnu linux audio messI remember GNU / Linux, 11 years from now, times when ALSA was not standardly shipped with Linux.
Back then ALSA still lacked good support for many SoundCards and was still a "baby project".
In that time what we used to have sound on Linux was OSSOpen Sound System. OSS emerged right after the first ever Linux sound system VoxWare (formerly known as the Linux Sound Driver).

Back in those days OSS was used for multimedia support on both GNU / Linux and BSD based free OSes. It was few years later when I heard and used ALSA for a fist time and it wasn't really a love from first sigth.

One can easily find out by the name ALSA it is a system especially built for the Linux kernel and that's one of the reasosn why *BSD systems has their custom separate sound system.
There is plenty of reasons why OSS was substituted with ALSA. Main reason was its commercial like license, OSS wasn't completely "open source" GPLed (free software), there was resctions on use of OSS for commercial goals.

With its emerge ALSA started to push away OSS slowly. Somewhere in 2003, alsa has officially entered the Linux kernel source and until 2005 it was the default standard for all GNU / Linux operating systems.

As of time of writting ALSA has become the only sound system to have support for multiple sound card devices for Linux.
My experiences with ALSA, however ain't so nice if I take a look in my past experiences.
Since the very beginning of using ALSA, I had plenty of troubles with configuring properly my sound card not to mention, even after configuring it the MIDI support was not there.
Besides all the troubles main problems were stemming from the many applications still written to use OSS as sound system and hence with those sound was impossible with ALSA.The most problematic thing about apps written with OSS in mind was all of them tried to stream sound via /dev/dsp (OSS Digital Sound Processor), since alsa did not used /dev/dsp those programs was soundless.

On the other hand OSS was creating issues as well, one severe problem with OSS was the inability to stream multiple sounds simultaneously, because each sound stream required to pass voice through /dev/dsp and usually there was only one /dev/dsp.

The message;

/dev/dsp: Device or resource busy
and the proceeding irritation that used to annoy us in the early GNU / Linux days had of course some raw workarounds hacks but generally the workaround did not fix problems always.

Introduction of alsa free us from /dev/dsp issues but on the other handy has created a whole ocean of new BIG problems …
ALSA has modular structure and this imposes a great problem nowdays. The modular architecture is generally a good idea, however the way this was implemented within ALSA is far away from clear and easy to understand by the end user and therefore makes it very unintuitive and obscure.
Alsa misses simplicity which somehow was partially in the days of OSS. Thinking over the general situation with Linux multimedia nowdays, I believe it was exactly ALSA Project responsible for the so delayed mass Desktop Linux adoption.

Many long year standing Linux users had certainly had the alsa troubles during new system installs (correct me if I'm wrong).
The only fix to multiple soundcard initialization problems was to download alsa source and compile from source and hence made it hard and discouraging for people giving Linux a try.
This kind of ALSA "brokenness" pattern continues even to this very day (in Debian) Linux and probably building the alsa system from source is among the good practices to have a functional Linux sound system…

With all said the historic reason why ALSA was not quickly adopted and still is not a preferred default system for many applications ported to Free Software OSes by commercial company vendors is clear. Its simply not working out of the box …

Hope some ALSA developers will read this post work on changing the crazy structure of ALSA over complexity. ALSA needs automate way to solve issues with itself, the configuration should be more trivial and unified if Linux has to become more attractive for Desktop adoption.

Anyways, after the few words of history and indicating my pesonal observations on ALSA. I will proceed and explain few things on how ALSA can be configured to support and play nice with OSS dependant programs as well some basic explanations on common incompatibility between esd and pulseaudio and how this can be fixed;.

To assure nowdays OSS API built programs and games would work with Alsa its necessery to have installed;

ALSA wrapper for OSS applications

On Debian, Ubuntu, Fedora and most Linux distributions the Alsa OSS compatability layer comes under a (deb / rpm) package named alsa-oss

To install OSS compatability on Debian, Ubuntu and the like Debian based distributions issue:

debian:~# apt-get install alsa-oss alsaplayer-oss
...

On Fedora and other rpm based distributions install is with:

[root@fedora ~]# yum install alsa-oss alsaplayer-oss
...

alsa-oss provides with a command called aoss that should be used to work around some issues with old applications still depending on OSS:

hipo@debian:~$ aoss programName

Using aoss is helpful especially in situations if you have to run programs which deal with MIDI and others which somehow want to use /dev/dsp

There is also alternative way to enable alsa native support for MIDI and OSS by loading 3 kernel modules:

debian:~# modprobe snd-seq-oss
debian:~# modprobe snd-pcm-oss
debian:~# modprobe snd-mixer-oss

Note! The three modules has to be separately build using kernel source at most cases and does not come with most Linux distributions, so on many installations (including my current), they will be missing. If for you they load properly or you have customly build them add them also to load on system boot, like so:

echo 'snd-seq-oss' >> /etc/modules
echo 'snd-pcm-oss' >> /etc/modules
echo 'snd-mixer-oss' >> /etc/modules

The Linux sound situation becomes even more messy when ESD enters the scene. Many of the novice new Linux users certainly don't remember (Enlightened Sound Daemon) . ESD historically preceded PulseAudio . Hence it will be good to mention ESD was used for few years in GNOME and in around 2006-2007 it was substituted by PulseAudio.
Many applications, however who was ported or written for Linux especially (the proprietary ported ones) was already built to work with ESD and even though newer GNOME releases was fully using pulseaudio, this (non free software apps and games) were still depending on ESD.

The situation was partially fixed by creation of module for pulseaudio which added emulation support for esd . This was done by a module library for pulseaudio called libprotocol-esound.so
The package for almost all Linux distributions which does the esd emulation via pulse is pulseaudio-esound-compat . In latest Fedora Linux pulseaudio-esound-compat is installed by default.
In Debian and other Linux distributions it might need to be installed via apt with;

debian:~# apt-get install pulseaudio-esound-compat
...

pulseaudio-esound-compat solves some of the ESD app incompability but not always …
Handy tool also worthy to mention in solving PulseAudio, OSS incompatibility issues is padsp

padsp is helpful in solving obsolete issues with OSS applications (trying to access /dev/dsp) and therefore unable to communicate with Pulseaudio
padsp – is a PulseAudio OSS Wrapper.

An example where padsp is helpful is in case of /dev/dsp errors like:

/dev/dsp: Device or resource busy
Could not open /dev/dsp

Another common problem with sound on Linux is when running windows applications (running windows games with wine).
Quite often sound fails to work since wine tries to directly communicate with alsa and fails because alsa sound channel is taken by pulseaudio.

To workaround wine issues with pulseaudio, one of the solutions is to temporary stop pulseaudio, before running the wine emulated application:

hipo@debian:~$ pulseaudio --kill

Later on when the windows wine emulation is completed, pulseaudio has to be started once again in order to make Pulseaudio applications produce sound again, e.g. one has to issue:

hipo@debian:~$ pulseaudio --start
Alternative way to workaround wine sound issues is by using a script to kill pulseaudio every second. Here is fix_pulseaudio_wine_sound_probs.sh script

This script was reported by many people as fix to problems with wine games failing to play sounds and music, anyhow I personally prefer using the stop / start pulseaudio method.

The picture below is taken from Wikipedia and illustrates, clearly the intergalactical complexity of sound systems on Gnu / Linux and BSD

I just hope one day this (OSS, ALSA, esd, Pulseaudio) mess will be over! In the mean time I hope my suggested work arounds helps someone. If someone has a better more unified script or solution please share in comments

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Happy New 2012 Year, few Bulgarian New Year traditions / customs

Sunday, January 1st, 2012

Happy 2012 New Year . Wish to everyone best of luck, good health and best of success in the new upcoming year!
There is few customs, which are very typical for Bulgarian Christmas and New Year.
As I'm so keen on tradition and I'm sure many non-bulgarians are not aware of the Bulgarian custom, I'll try to name few of them and shed some light for foreigners who are about to celebrate the Christmas or New year eve in Bulgaria.

One is the back (spine) tapping, done by youngsters to elders with a stick made of cornel-tree and decorated in a very special beautiful way.

Here is how the stick the youngsters use to wish happy new year in a traditional bulgarian custom way.Survaknica Bulgariar New Year (Survane) new year custom
The back tapping to the elder is accompanied by famous words in Bulgarian saying:

Surva, Surva Godina!
Chervena Qbylka v Gradina,
edyr klas na niva,
golqm grozd na loza,
jylt mamul na lesa,
pylna kyshta s deca!
Jivo-zdravo do godina,
do godina do Amina!

This translated to english says something like:

Healthy (Complete), Healthy Year!
Red Apple in a Garden,
Large grapes in the vineyeard,
Yellow corn in the field,
full house with children!
Living-healthy until next year
in these year until the next one.

Actually this New Yearly wishings had different minor text variations in different regions of Bulgaria, but the main meaning is anyhow preserved.

Surva Surva Godina, Vesela Godina kid back tapping an older man Bulgaria
Kid using Survaknica to back tap some older man according to our tradition

You can see how simple and the same time meaningful those wishings are. They accent to the main things which were important for our forefathers. The things on which the yearly daily life depends.

Here is a video of some children in the kinder garden reciting the Surva, Surva wishing holding Survaknici

I've seen for the last 10 years these tradition as a consequence of the internationalization is starting to disappear. Now most of the times only in villages and some small regions these tradition is still practiced.
In cities gipsys are going in the early morning of the New Year morning and knocking on each apartment door offering a back tapping. Once they back tap you with Survaknica and wish you good things you're supposed to give them some food, candies and / or money 😉

Its also common that in the morning of the New Year a lot of folklore ensambles dance on the centers of cities and villages or sing Bulgarian folklore songs.

Bulgarian Folklore Choire

Some of the other things which are a kind of traditional on New Year is to go out on the city center and fire up some fires and dance some traditional dance we call Horo near the camping fire.


 

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How to install and configure Jabber Server (Ejabberd) on Debian Lenny GNU / Linux

Wednesday, December 28th, 2011

Ejabberd server erlang logo hedgehog

I've recently installed a jabber server on one Debian Lenny server and hence decided to describe my installations steps hoping this would help ppl who would like to run their own jabber server on Debian . After some research of the jabber server softwares available, I decided to install Ejabberd

The reasons I choose Ejabberd is has rich documentation, good community around the project and the project in general looks like one of the best free software jabber servers available presently. Besides that ejabberd doesn't need Apache or MySQL and only depends on erlang programming language.

Here is the exact steps I followed to have installed and configured a running XMPP jabber server.

1. Install Ejabberd with apt

The installation of Ejabberd is standard, e.g.:

debian:~# apt-get --yes install ejabberd

Now as ejabberd is installed, some minor configuration is necessery before the server can be launched:

2. Edit /etc/ejabberd/ejabberd.cfg

Inside I changed the default settings for:

a) Uncomment%%override_acls.. Changed:

%%%% Remove the Access Control Lists before new ones are added.%%%%override_acls.

to

%%
%% Remove the Access Control Lists before new ones are added.
%%
override_acls.

b) Admin User from:

%% Admin user
{acl, admin, {user, "", "example.com"}}.

to

%% Admin user
{acl, admin, {user, "admin", "jabber.myserver-host.com"}}.

c) default %% Hostname of example.com to my real hostname:

%% Hostname
{hosts, ["jabber.myserver-host.com"]}.

The rest of the configurations in /etc/ejabberd/ejabberd.cfg can stay like it is, though it is interesting to read it carefully before continuing as, there are some config timings which might prevent the XMPP server from user brute force attacks as well as few other goodies like for example (ICQ, MSN , Yahoo etc.) protocol transports.

3. Add iptables ACCEPT traffic (allow) rules for ports which are used by Ejabberd

The minimum ACCEPT rules to add are:

/sbin/iptables -A INPUT -p tcp -m tcp --dport 22 -j ACCEPT
/sbin/iptables -A INPUT -p tcp -m tcp --dport 5222 -j ACCEPT
/sbin/iptables -A INPUT -p udp -m udp --dport 5222 -j ACCEPT
/sbin/iptables -A INPUT -p tcp -m tcp --dport 5223 -j ACCEPT
/sbin/iptables -A INPUT -p udp -m udp --dport 5223 -j ACCEPT
/sbin/iptables -A INPUT -p tcp -m tcp --dport 5269 -j ACCEPT
/sbin/iptables -A INPUT -p udp -m udp --dport 5269 -j ACCEPT
/sbin/iptables -A INPUT -p tcp -m tcp --dport 5280 -j ACCEPT
/sbin/iptables -A INPUT -p udp -m udp --dport 5280 -j ACCEPT
/sbin/iptables -A INPUT -p tcp -m tcp --dport 4369 -j ACCEPT
/sbin/iptables -A INPUT -p udp -m udp --dport 4369 -j ACCEPT
/sbin/iptables -A INPUT -p tcp -m tcp --dport 53873 -j ACCEPT

Of course if there is some specific file which stores iptables rules or some custom firewall these rules has to be added / modified to fit appropriate place or chain.

4. Restart ejabberd via init.d script

debian:~# /etc/init.d/ejabberd restart
Restarting jabber server: ejabberd is not running. Starting ejabberd.

5. Create ejabberd necessery new user accounts

debian:~# /usr/sbin/ejabberdctl register admin jabber.myserver-host.com mypasswd1
debian:~# /usr/sbin/ejabberdctl register hipo jabber.myserver-host.com mypasswd2
debian:~# /usr/sbin/ejabberdctl register newuser jabber.myserver-host.com mypasswd3
debian:~# /usr/sbin/ejabberdctl register newuser1 jabber.myserver-host.com mypasswd4
...
etc.

ejabberdctl ejabberd server client (frontend) has multiple other options and the manual is a good reading.

One helpful use of ejabberdctl is:

debian:~# /usr/sbin/ejabberdctl status
Node ejabberd@debian is started. Status: started
ejabberd is running

ejabberctl can be used also to delete some existent users, for example to delete the newuser1 just added above:

debian:~# /usr/sbin/ejabberdctl unregister newuser jabber.myserver-host.com

6. Post install web configurations

ejabberd server offers a web interface listening on port 5280, to access the web interface right after it is installed I used URL: http://jabber.myserver-host.com:5280/admin/

To login to http://jabber.myserver-host.com:5280/admin/ you will need to use the admin username previously added in this case:
admin@jabber.myserver-host.com mypasswd1

Anyways in the web interface there is not much of configuration options available for change.

7. Set dns SRV records

I'm using Godaddy 's DNS for my domain so here is a screenshot on the SRV records that needs to be configured on Godaddy:

GoDaddy DNS SRV records screenshot

In the screenshto Target is the Fually qualified domain hostname for the jabber server.

Setting the SRV records for the domain using Godaddy's DNS could take from 24 to 48 hours to propagate the changes among all the global DNS records so be patient.

If instead you use own custom BIND DNS server the records that needs to be added to the respective domain zone file are:

_xmpp-client._tcp 900 IN SRV 5 0 5222 jabber.myserver-host.com.
_xmpp-server._tcp 900 IN SRV 5 0 5269 jabber.myserver-host.com.
_jabber._tcp 900 IN SRV 5 0 5269 jabber.myserver-host.com.

8. Testing if the SRV dns records for domain are correct

debian:~$ nslookup
> set type=SRV
> jabber.myserver-host.com
 ...
> myserver-host.com

 If all is fine above nslookup request should return the requested domain SRV records.
You might be wondering what is the purpose of setting DNS SRV records at all, well if your jabber server has to communicate with the other jabber servers on the internet using the DNS SRV record is the way your server will found the other ones and vice versa.

DNS records can also be checked with dig for example

$ dig SRV _xmpp-server._tcp.mydomain.net

[…]

;; QUESTION SECTION:
;_xmpp-server._tcp.mydomain.net. IN SRV

;; ANSWER SECTION:
_xmpp-server._tcp.mydomain.net. 259200 IN SRV 5 0 5269 jabber.mydomain.net.

;; ADDITIONAL SECTION:
jabber.mydomain.net. 259200 IN A 11.22.33.44

;; Query time: 109 msec
;; SERVER: 212.27.40.241#53(212.27.40.241)
;; WHEN: Sat Aug 14 14:14:22 2010
;; MSG SIZE rcvd: 111

9. Debugging issues with ejabberd

Ejabberd log files are located in /var/log/ejabberd , you will have to check the logs in case of any issues with the jabber XMPP server. Here is the three files which log messages from ejabberd:

debian:~$ ls -1 /var/log/ejabberd/
ejabberd.log
erl_crash.dump
sasl.log

I will not get into details on the logs as the best way to find out about them is to read them 😉

10. Testing ejabberd server with Pidgin

To test if my Jabber server works properly I used Pidgin universal chat client . However there are plenty of other multiplatform jabber clients out there e.g.: Psi , Spark , Gajim etc.

Here is a screenshot of my (Accounts -> Manage Accounts -> Add) XMPP protocol configuration

Pidgin account configuration XMPP on debian Linux
 

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Poderosa a tabbed Terminal Emulator (PuTTY Windows Alternative)

Tuesday, December 6th, 2011

Even though, I rarely use Windows to connect to remote servers using SSH or Telnet protocols in some cases I’m forced to do that (in cases I’m away from my Linux notebook). I’m doing my best to keep away from logging anywhere via SSH using Windows as when using Windows you never know what kind of spyware, malware or Viruses is already on the system, not to mention Microsoft are sniffing a lot if not everything which is typed on the keyboard… Anyways, usually I use Putty as a quick way to access a remote SSH, however pitily PuTTY lacks an embedded functionality for Tabs and each new connection to a server I had to run a new instance of PuTTY. This is okay if you need to access a single server but in some cases where access to multple servers is necessery lacking the tab functionality and starting 10 times putty is really irritating and one forgets what kind of connection is present on which PuTTY instance.

Earlier on, I’ve blogged about the existence of PuTTY Connection Manager PuTTY add-on program which is a PuTTY wrapper which enables PuTTY to be used with Connection Tabs feature, however installing two programs is quite inconvenient, especially if you have to do this every few days (in case if travelling a lot).

Luckily there is another terminal emulator free program for Windows called PodeRoSA which natively supports a tabbed Secure Shell connections.
If you want to get some experience with it check out Poderosa’s website , here is also a screenshot of the program running few ssh encrypted connections in tabs on a Windows host.

Poderosa Windows ssh / telnet tabs terminal emulator screenshot
Another good reason that one might consider using Poderosa instead of PuTTY is the Apache License under which Poderosa is developed. Currently the Apache License is compatible with GPL free software license which makes the program fully free software. The PuTTY license is under BSD and MIT and some other weird custom license not 100% compatible with GPL and hence PuTTY can be considered less free software in terms of freedom.

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