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My computer is under Ubuntu 24.10, the last version available.

I installed VirtualBox, with the last version available in the repo is 7.0.20, even 7.0.22 or 7.1.4 exist.
By default the "Extension Pack" is not installed.

I download the file here:
https://www.virtualbox.org/wiki/Download_Old_Builds

And when I tried to install the file manually in VirtualBox, I had an error "shell problem", because the shell I used ("Elvish") is not present in file "/etc/shells".
VirtualBox was explicit to the cause of the problem.

As "root" I edit the file, and add the line "/usr/local/bin/elvish" at the end of the file.

I retry, and it's working...
The "Extension Pack" is there now.


In add, this entry in the file solved another problem I had.
In nautilus/gnome-shell, it's possible to open a shell with the right-click and "open in terminal" and to open it directly in the selected directory.
But, after I switch to "elvish", the directory was always my "home" directory.
I didn't found a solution by searching on internet.

Now, by adding the entry in "/etc/shells", The command open my Elvish shell session directly in the directory !


Fantastic ! 2 problems solved in one operation.
 

[Pour les lecteurs français, cliquez sur le drapeau en haut à gauche pour basculer sur la page en français]


I discovered recently the new shell named "Elvish".
Sounds nice.

https://elv.sh/

1) Installation :

The stable version at this moment is 0.21.0, but check on the site to get the latest release...

curl -so - https://dl.elv.sh/linux-amd64/elvish-v0.21.0.tar.gz | sudo tar -xzvC /usr/local/bin


2) Setup as default shell :

sudo usermod -s /usr/local/bin/elvish <username>
cat /etc/passwd | grep <username>

And after reconnect with your user, the default shell is now in place.


3) Functions :

If you are familiar with bash, ksh, or sh, it sounds similar.

In bash, I use frequently the "ll" command.
On different unix with no bash, I create an alias to define it as "ls -al".

It's a quite bit different on elvish.
No alias but functions.

fn ll {|@args|
    ls -al $@args
}


4) RC file :

https://elv.sh/ref/command.html#rc-file

"RC file" is the equivalent of "~/.bash_profile" for bash, or "~/.profile" for ksh.

mkdir -p ~/.config/elvish/
vi ~/.config/elvish/rc.elv

Inside I put the function I defined previously, and each time, I start a terminal, my "ll" is ready tu use !


5) Next :

I will continue to explore it.
I'am going to translate some of my shell scripts in Elvish.

The "peach" ("parallel each") command looks like powerful.


6) References:

The documentation seems to be complete and clear.
https://elv.sh/learn/
https://elv.sh/learn/tour.html
https://elv.sh/ref/
https://elv.sh/ref/command.html

Forum:
Not a lot of threads for the moment.
https://bbs.elv.sh/

Icon of this page found here:
https://icons8.com/icons/set/elvish
 

Hello !

A small message just saying I finished to migrate from version 5 to 6 of Guppy.

Actually, I tried it for some times. I started at several times, but in each trys, time or a blocking problem stopped me.

Finally, it's done

[Pour les lecteurs français, cliquez sur le drapeau en haut à gauche pour basculer sur la page en français]

Here we are, I migrate to Fedora 32, and the look & feel continues to improve version after version.

No big issues to upfdate from F31, except VirtualBox that I was obliged to de-install.

But after install I immediatly install the latest version of VirtualBox which is compatible with F32.

Actually, at each new version I'am waiting to migrate that VirtualBox new update compatible with the new OS is available.

[Pour les lecteurs français, cliquez sur le drapeau en haut à gauche pour basculer sur la page en français]

I'am still working as DBA, as my main job, just sitting on my pile of knownledge. Mainly Oracle, but following PostGreSQL as second opportunity.

But for my sanity, I read other technologies around.

NoSQL DB's doesn't impress me much. It's just a fashion event. It's becoming a technology among another, with strong and weak points, not the revolution acclaimed at the beginning.

From my point of view, Graph DB's are more interesting, and the use is underrated for the moment.

And for Fun, I continue to code for myself. For some years, after trying multiple languages, I like and I come back regurlaly to RUBY.

Why RUBY?
Well the syntax is elegant and light, the code is compact and readable even after weeks or months.
I use it for scripting and for GUI.
For GUI, I use the jRuby with Swing.

Why not Java?
I tried it in the past, but I never like it, too verbose.
"100 lines of Java can be done in 10 lines in Ruby" : it's common sentence in Ruby world, and after trying it, ... it's true.

Why not python?
Well, I didn't catch up. If necessary, I thing I can code, but I prefer Ruby. It's more a question of feeling.

After years, the wisdom is to decide to not decide. Eveybody can claim to like and support it's own programming language. If it's mandatory to choose one, it's should be 'Ada'. But it's another story.

One of my favorite programming language is Ruby. And I will write some pages on it.

[Pour les lecteurs français, cliquez sur le drapeau en haut à gauche pour basculer sur la page en français]

Monday 09 septembre was in Paris (France) a big Oracle show for the launch of the Oracle Database 12c.

Tom Kyte was the "guest guest" of this exhibition. His presentation was very clear, specially if you consider that he was the only one who talked in english. It was a really nice moment.
As he said, he lived 2 majors rupture of Oracle Database:
* First, 34 years ago with Oracle 6, when the database became multi-processes.
* And now, with the 12c, and the 600 new features, specially the plugable databases.

It's why I put the title "a new era?".

In a quick presentation, it was showed how to duplicate a database inside a CDB (Container DataBase). The operation is very fast, as it's just a declaration. The datafiles are not duplicated immediatly. It's like in VirtualBox, when a server is linked to the source. Only the blocks modified are written to disk.
It's very impressive. But I notice a limitation: the source database was stopped. This feature should be better with a kind of "begin backup" mode, to not impact the end-users, specially for duplicating a production DB? It's something to investigate.

It's a lot of new features for DataGuard (DG), actually in "Active DG" payable option, of course.
* Now standby environment are not solely, and trying to connect to each other. A new kind of structure, similar of the RAC architecture, bounds them and improve the communication as a global system.
* Another improvement is the synchronous replication (FAR Sync) on long range, with the "repeater" server.
* It's coupled with the "FAST Sync" to speed up the synchronous commit on DB database.

It's was another nice presentation from the CERN which is a beta-tester of the 12c. They have more than 100 PB (1PB = 1024 TB) of datas, and still increasing. They were facing 2 difficulties::
* Long range duplication of datas: eased with the new DG features.
* Transaction errors: when a transaction is lost (disconnected) around the commit, it's possible to redo it automatically through the JDBC driver (only this one for the moment). This sounds useful for them a they have massive insertion of datas. But for standard OLTP/ERP users, they just have to reconnect, query the datas inside the application to search if the insert was done or not.

Another interesting presentation of the automatic "online compression" without any scripting, coupled with the "multi-tiering" of datas on different quality of disks. Available in "advanced compression" payable option.
This is only available for SUN/zfs storage. I guess, in the next versions, more storage vendors (EMC, Netapp, ...) will be compatible.

No big announcements for the RAC. The only one, is the "FLEX ASM". This means that a Node of the RAC is not obliged to run a ASM instance, it can be a client of an another one.

Concerning the licensing, no mentions, of course.
It seems that the CDB multi-tennant will an additionnal license from the database. And CDB single-tennant will be included in the cost of the DB.
It's also possible to create a database in the traditionnal way. But the use of the CDB single-tennant will ease the migration process.



Finally, at the end, a very non-oracle presentation of Jean-François CLERVOY, a french astronaut, who went 3 times in space.
His presentation of his experience was impressive, and would think to remain humble face to the vastness of the space and the fragility of our planet.
 

[Pour les lecteurs français, cliquez sur le drapeau en haut à gauche pour basculer sur la page en français]

Finally the official release of Database 12c (12.1.0.1.0) is available on Oracle Technet for Windows / Linux / Solaris for the moment.

http://www.oracle.com/technetwork/database/enterprise-edition/downloads/index.html

I download the documentation to read the new features.

The big one is the "Database container" (CDB) which is a brand new concept. But I don't think it will be an universal features for all companies.



The most interesting improvement I read is there:

http://docs.oracle.com/cd/E16655_01/server.121/e17906/chapter1.htm#AREANO02524

1.7.2.1 Oracle ACFS Support for All Oracle Database Files

"Oracle ACFS provides support for all database files."


If I understand correctly, it should be possible to have the benefit of ASM (via ACFS) and to manage databases with regular file systems, for standalone and RAC databases.
This is a major improvement !



Also, next monday, in Paris (France), it will be an event for the launch of the Database 12c:

http://www.oracle.com/webapps/events/ns/EventsDetail.jsp?p_eventId=168982

Tom Kyte will be there.

I registered to it, so I will write a little comment after that.
 

[Pour les lecteurs français, cliquez sur le drapeau en haut à gauche pour basculer sur la page en français]

By default on my CentOS installation, I have "Movie Player" to watch videos and to listen musics.
But most of the time it can't read the videos.

So I tried to install a more versatile player.

At the beginning, I tried to install "VLC". But after a lot of problems and error messages, I gived up.
It seems that it's not possible to install easily VLC on CentOS.


And after some search in forums, I found the graal : "mplayer".

Please read the description on wikipedia:
http://en.wikipedia.org/wiki/MPlayer

That sounds a powerful player and very light in term of CPU consumption.


Important note:
MPlayer is a very good player but it don't have an easy GUI interface.
So to use it day to day, a "Frontends" should be installed.

Here the list of "MPlayer Frontends" available:
http://www.mplayerhq.hu/design3/projects.html

2 of them, seems to be very popular: "GnomeMplayer" and "SMPlayer"


For "SMPlayer", it sounds good, but no rpm for CentOS/RHel.
http://smplayer.sourceforge.net/


So I installed "GnomeMplayer"

Here the main site:
https://sites.google.com/site/kdekorte2/gnomemplayer

Here the blog of the author:
http://kdekorte.blogspot.fr/search/label/GnomeMplayer



I installed them last year, and it was working perfectly for a while.

But recently, I upgraded to CentOS 6.4, and I had some trouble with it.

After some investigations:

yum list mplayer

Installed Packages
mplayer.x86_64          4:1.2-91_snap20130509.el6        @atrpms
Available Packages
mplayer.i686            1.0.4-3.el6                      linuxtech



yum list gnome-mplayer

Installed Packages
gnome-mplayer.x86_64    1.0.0-12.el6                     @atrpms



Here the last version:
http://mplayerhq.hu/design7/news.html

When I write this article, it's:
2013-05-05, Sunday :: MPlayer 1.1.1 update

Obviously, I have a mismatch somewhere.


For "GnomeMplayer", only 1.0.0 version is available at "atrpms" repository.
In the blog, the version 1.0.7 is available.
But in the download page:
http://code.google.com/p/gnome-mplayer/downloads/list
The version 1.0.8 is ready...



First attempt to re-install "MPlayer" (failed):

So I downloaded tha last version from:
http://mplayerhq.hu/design7/dload.html

Player 1.1.1 release     HTTP (xz compressed, 11 MB)
MPlayer-1.1.1.tar.xz

And installed it manually:
yum remove gnome-mplayer
yum remove mplayer

yum repolist

I keep only:
* epel
* rpmfusion-free-updates
* rpmfusion-nonfree-updates
I put all the other in the "--disablerepo" clause.

yum list mplayer --disablerepo=base,elrepo,extras,rpmforge,updates,linuxtech,atrpms

Loaded plugins: fastestmirror, refresh-packagekit
Loading mirror speeds from cached hostfile
 * epel: nl.mirror.eurid.eu
 * rpmfusion-free-updates: rpmfusion.famillecollet.com
 * rpmfusion-nonfree-updates: rpmfusion.famillecollet.com
Available Packages
mplayer.x86_64         1.0-0.140.20120205svn.el6.1     rpmfusion-free-updates

Sounds good.

yum install mplayer --disablerepo=base,elrepo,extras,rpmforge,updates,linuxtech,atrpms


Hum, the installer, in add, of "mplayer" try to install 8 others components, as "ffmpeg".
But it detects conflicts:

Transaction Check Error:
  file /usr/lib64/libfaad.so.2.0.0 from install of faad2-libs-1:2.7-2.el6.3.x86_64 conflicts with file from package libfaad2-1:2.7-18.el6.x86_64
  file /usr/lib64/libswresample.so.0 from install of ffmpeg-libs-0.10.7-1.el6.x86_64 conflicts with file from package libswresample0-1.2.1-59.el6.x86_64
  file /usr/lib64/libswscale.so.2 from install of ffmpeg-libs-0.10.7-1.el6.x86_64 conflicts with file from package libswscale2-1.2.1-59.el6.x86_64
  file /usr/lib64/libpostproc.so.52 from install of ffmpeg-libs-0.10.7-1.el6.x86_64 conflicts with file from package libpostproc52-1.2.1-59.el6.x86_64

My solution:
yum remove ffmpeg

Do again:
yum install mplayer --disablerepo=base,elrepo,extras,rpmforge,updates,linuxtech,atrpms

But no way. By the difficulties, I give up and I found a better solution.




Second attempt to re-install "MPlayer" (success):

Follow instructions from:
http://wiki.centos.org/TipsAndTricks/MultimediaOnCentOS

Step 1 and Step 2, good

For Step 3, I did it, but in add, some newer codec must be installed.
( see discusion in: http://www.linuxquestions.org/questions/linux-software-2/install-mplayer-on-centos-6-0-64bit-915855/
)

Note: on page: http://www.mplayerhq.hu/MPlayer/releases/codecs/
all-20110131.tar.bz2 is still the lastest release available.

wget www1.mplayerhq.hu/MPlayer/releases/codecs/all-20110131.tar.bz2

bunzip2 all-20110131.tar.bz2

tar xvf all-20110131.tar

cd all-20110131

more README
...
If you use a prebuilt MPlayer package it will most likely be /usr/lib/codecs,
see the documentation of your package for details.
...

ll /usr/lib/codecs

yes, for me all the codecs are there

mv * /usr/lib/codecs
 

So here, "MPlayer is installed". So I need to install a latest version of "gnome-mplayer"

I tried to install the version 1.0.8 from the source and to compile it. No way...
So I browsed the web to find a latest version, as only version 1.0.0 is available at "atrpms".

yum list gnome-mplayer
Installed Packages
gnome-mplayer.x86_64                 1.0.0-12.el6              @atrpms

yum list gnome-mplayer  --disablerepo=base,elrepo,extras,rpmforge,updates,linuxtech,atrpms


Here the page, I found useful informations
http://pkgs.org/download/gnome-mplayer
http://pkgs.org/centos-6-rhel-6/puias-i386/gnome-mplayer-1.0.3-2.puias6.i686.rpm.html

So for my CentOS 6, a RPM version 1.0.4 is available in "Nux Dextop" yum repository.

http://pkgs.org/centos-6-rhel-6/nux-dextop-x86_64/gnome-mplayer-1.0.4-16.el6.nux.x86_64.rpm.html

Install Howto

1. Download the latest "nux-dextop-release" RPM from

http://li.nux.ro/download/nux/dextop/el6/x86_64/

it seems to be:
nux-dextop-release-0-2.el6.nux.noarch.rpm

Note:
smplayer 0.8.5 (smplayer-0.8.5-1.el6.nux.x86_64.rpm) seems to be available here, but I don't installed it now, maybe later.



2. Install nux-dextop-release rpm:

rpm -Uvh nux-dextop-release*rpm


3. Install gnome-mplayer rpm package:

yum install gnome-mplayer

yum list gnome-mplayer
...
Installed Packages
gnome-mplayer.x86_64            1.0.4-16.el6.nux             @nux-dextop


Conclusion:

Finally MPlayer with the gnome-mplayer version 1.0.4 is installed on my CentOS 6, and it's working.
It's what I need. So I'am happy, even if I spent a long time to install it.

 

[Pour les lecteurs français, cliquez sur le drapeau en haut à gauche pour basculer sur la page en français]


As I said in a previous note, I work more and more with Linux, and less and less with windows.
I tried to start my windows in VirtualBox as physical installation guest in a CentOS host. But I never succeed to start windows.
The most important things to me was to have a access to the files stored on the NTFS partition. And also to run some programs existing in Windows world and not Linux.



1) First, I can access my NTFS disks with

Here it's the official site:
http://www.tuxera.com/community/ntfs-3g-download/

But the packages are available thru EPEL repository.

I don't remind how I setup the EPEL repo, but here the command to check if the repo is available for yum:

#List new repo:
yum repolist

yum install ntfs-3g ntfsprogs

Installed:
  ntfs-3g.x86_64 2:2011.4.12-5.el6                                ntfsprogs.x86_64 2:2011.4.12-5.el6


And after that, any NTFS volume from my windows or external hard disk can be mounted and the content can be visible from my Linux.
Also all accesses can be done (not only reading).
For one year from now, it's working perfectly.



2) Second step, I installed WINE which can run windows programs inside Linux.

Well, it's pretty good. I didn't try all the programs, but I have some, which are very useful and I don't find the equivalent in Linux.
Also, I tried my favorite editor in windows : Crimson editor. I can use it but, when I save a shell program, it loose all its running credentials. too bad...
I hope a day, it will be ported in Linux.



At this point I can use all Windows stuff I need, without windows. Marvelous.
 

It's a long time I didn't write a note.

Usual excuses. Time is passing fast. Family, Kid, Work, and the Lazy indolent of human nature, should be enough to describe this state !


What happens since I write my last notes.

Actually a plenty of work and problems.

To summarize, I installed Cent0S 6.0 with the Nouveau NVidia driver, and I was very happy to succeed.

Confident in the future, I accept to upgrade my centOS to a new version a kernel: 6.0

And there the problems begin. When I start, no GUI interface, even no access with a prompt.
Oups!
Hopfully, the network interface was working properly. The only possibility to connect to CentOS was from another PC on the network with telnet/SSH connection. I spent 2 weeks like this trying to browse internet to find a solution (My windows on first boot continue to work properly, so the problem was not a big problem).

After some times, CentOS was ready for download, and I upgrade the kernel another time.
Here, after the boot, no GUI connection, but a big improvement, the command line was working.

I became a expert to install/remove the Nouveau driver of NVidia. But no more chance. It was working on CentOS 6.0, but not after...

By browsing dozens of internet pages
At the end, I found a note explaining to not use the official driver from NVidia but installing the "kmod-nvidia" from elrepo.

Here the complete link references:

"
Install elrepo in place of nvidia driver

[CentOS] nvidia failure with new kernel
http://lists.centos.org/pipermail/centos/2011-January/104548.html

Alternatively, you could use the nvidia driver packages from elrepo.org:
http://elrepo.org/tiki/kmod-nvidia

You do need to set up elrepo if you have not used it before.
Instructions are here:
http://elrepo.org/tiki/tiki-index.php

You will probably also want to install the yum priorities plugin to
avoid conflicts between elrepo and the base repos (or any other
third-party repos you may use).
http://wiki.centos.org/PackageManagement/Yum/Priorities
"


And it works! Even, I upgrade to CentOS 6.3 (twice), and recently to 6.4, and wonderful, the package too, and at startup my GUI configuration of my graphic card continues to work properly.

Finally, this story is behind me, but I was closed to give up linux as graphical interface on my laptop.

Since, I work more and more on linux, and less and less on windows.
I apreciate the simplified interface, compared to the flashy one of windows.