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cron: you can’t split multiple lines command

May 12th, 2015 No comments

Remember: you can’t split multiple lines command inside cron like you do in shell with the \

 

 

SOURCE:

https://www.pantz.org/software/cron/croninfo.html
http://www.alleft.com/sysadmin/common-cron-mistakes/

Categories: Linux Tags:

Debian Wheezy: change console resolution

October 20th, 2013 No comments

I’m running a VM with Debian Wheezy on a Parallels Desktop installation on a MacBook Pro early 2011 and Debian can’t get automatically the correct video resolution.

To correct it, edit /etc/default/grub and add these 2 lines

[cce_bash]GRUB_GFXMODE=1280x800
GRUB_GFXPAYLOAD_LINUX=1280x800[/cce]

 

Enjoy big_grin

 

 

SOURCE: how to change the console resolution?

Categories: Debian Tags:

How a 4-pin tactile switch works

February 22nd, 2013 No comments

Here it is an application example of a type of a 4-pin tactile switch

4-Pin Tactile Switch

Each pin is already in contact with in the pin in front of it. When you press the button, all pins are connected together.

Here the switch disassembled

4-pin tactile switch disassembled

The rounded metal plate, in the bottom of the picture, is placed upon the the three metal parts, that you see in the switch base in the left of the picture.

This plate is a little concave, so when the button is unpressed, it only connects the metal parts on the sides

When you press the button, you are going to press in the center of the rounded metal plate and it will connect all the 3 metal parts.

This way, the circuit is closed and all pins can connect together.

But how it is possibile?

Here a schema I drew

4pin_tactile_switch_schema

Red and blue lines show how pins and metal parts are connected together internally. So when the rounded metal plate touches all the three metal parts, it closes the circuit.

 

Enjoy :)

Categories: Ubuntu Tags:

Error: XML: Cacti version does not exist

April 18th, 2012 No comments

OS: CentOS 6.2
Cacti version: 0.8.8

If you get the error in subject importing a template, simply edit /var/www/cacti/include/global_array.php, at line 558 add a comma at the end

[cce_bash]"0.8.7i" => "0023",[/cce]

and after it add a new line

[cce_bash]"0.8.8" => "0024"[/cce]

 

Enjoy :)

Categories: Linux Tags: ,

How-to: install mssh on Fedora 16

March 5th, 2012 No comments

Form Debian Unstable packages list
http://packages.debian.org/source/unstable/mssh
download
mssh_1.2.orig.tar.gz
mssh_1.2-1.1.diff.gz

Untar both files

[cce_bash]tar xzf mssh_1.2.orig.tar.gz
gunzip mssh_1.2-1.1.diff.gz[/cce]

Apply the patch

[cce_bash]patch -p0 < mssh_1.2-1.1.diff[/cce]

Enter mssh directory

[cce_bash]cd mssh-1.2/[/cce]

Be sure you have installed the following packages

[cce_bash]su -c "yum install GConf2-devel gtk2-devel vte-devel"[/cce]

Run configure

[cce_bash]./configure[/cce]

Run make

[cce_bash]make[/cce]

Then make install (as root)

[cce_bash]su -c "make install"[/cce]

 

Enjoy :)

Categories: Fedora, Linux Tags: , , ,