The JetBrains I.D.E. software .

I tested the JetBrains Rider, the emerging .NET I.D.E. from JetBrains in the past.
Is good and this is new into the I.D.E. area of development.
What is this software? 
The JetBrains Rider is a new .NET I.D.E. based on the IntelliJ platform and ReSharper.
First I take a look into my Fedora distro to see it is something about JetBrains:

[root@localhost mythcat]# dnf search jetbrains
Last metadata expiration check: 1:19:59 ago on Tue Feb 21 12:42:57 2017.
============================ N/S Matched: jetbrains ============================
jetbrains-annotations-javadoc.noarch : Javadoc for jetbrains-annotations
jetbrains-annotations.noarch : IntelliJ IDEA Annotations

I download the archive from the official website. I extract all files ...

[mythcat@localhost ~]$ cd Rider-171.3085.362/bin/
[mythcat@localhost bin]$ ll
total 7120
-rw-r--r--. 1 mythcat mythcat    2568 Feb 15 23:02 backend-log.xml
-rwxr-xr-x. 1 mythcat mythcat     217 Feb 15 23:02 format.sh
-rwxr-xr-x. 1 mythcat mythcat   23072 Feb 15 23:02 fsnotifier
-rwxr-xr-x. 1 mythcat mythcat   29648 Feb 15 23:02 fsnotifier64
-rwxr-xr-x. 1 mythcat mythcat   26453 Feb 15 23:02 fsnotifier-arm
-rw-r--r--. 1 mythcat mythcat   10491 Feb 15 23:02 idea.properties
-rwxr-xr-x. 1 mythcat mythcat     268 Feb 15 23:02 inspect.sh
-rw-r--r--. 1 mythcat mythcat 3449944 Feb 15 23:02 libyjpagent-linux64.so
-rw-r--r--. 1 mythcat mythcat 3679036 Feb 15 23:02 libyjpagent-linux.so
-rw-r--r--. 1 mythcat mythcat    4138 Feb 15 23:02 log.xml
-rwxr-xr-x. 1 mythcat mythcat     410 Feb 15 23:02 printenv.py
-rwxr-xr-x. 1 mythcat mythcat     590 Feb 15 23:02 restart.py
-rw-r--r--. 1 mythcat mythcat     359 Feb 15 23:02 rider64.vmoptions
-rw-r--r--. 1 mythcat mythcat    9222 Feb 15 23:02 rider.png
-rwxr-xr-x. 1 mythcat mythcat    6619 Feb 15 23:02 rider.sh
-rw-r--r--. 1 mythcat mythcat     367 Feb 15 23:02 rider.vmoptions

After that, I started with rider.sh script:

[mythcat@localhost bin]$ ./rider.sh 
[YourKit Java Profiler 2016.02-b43] Log file: /home/mythcat/.yjp/log/Rider10-17590.log
Feb 21, 2017 2:05:43 PM java.util.prefs.FileSystemPreferences$6 run
WARNING: Prefs file removed in background /home/mythcat/.java/.userPrefs/prefs.xml
Installation home directory: /home/mythcat/Rider-171.3085.362
System directory: /home/mythcat/.Rider10/system
Config directory: /home/mythcat/.Rider10/config
Log directory: /home/mythcat/.Rider10/system/log
Full cold solution load with caches took 22053 milliseconds.

The result of this command was great.
This software come with a good wizard interface.
The application has many ways to deal with your source code and settings for any user. The colors of this software are ergonomic for users. They are:

• Memory: 4 GB or higher
• Operating system:
  • Windows 10, 8.1, 8 or 7. 64-bit distributions only.
  • OS X 10.10+. 64-bit distributions only.
  • Linux. 64-bit distributions only.

Fedora 25 and fix python modules.

This tutorial is a simple way to fix your python modules under Fedora distro.
I used Fedora 25 and python 2.7.13 version.
First try to use this command:

pip freeze --local | grep -v '^\-e' | cut -d = -f 1  | xargs -n1 pip install -U

This command will try to update based by:

• to skip "-e" package definitions;
• the newer versions of pip allow you to list outdated python modules;
• added -n1 to xargs, prevents stopping everything if updating one python module fails;

If you got this error about Python.h error:

...fatal error: Python.h...

Use this command to install the development library of Python:

[root@localhost mythcat]# dnf install python-devel.x86_64 python-devel.i686

Try to install also the devel libs for each error include.
Another example is this lib: opensslv.h
So install this:

[root@localhost mythcat]# dnf install openssl-devel.x86_64 
Last metadata expiration check: 1:58:33 ago on Thu Apr 20 18:52:10 2017.
Dependencies resolved.
================================================================================
 Package              Arch          Version                Repository      Size
================================================================================
Installing:
 openssl-devel        x86_64        1:1.0.2k-1.fc25        updates        1.5 M

Transaction Summary
================================================================================
Install  1 Package

Total download size: 1.5 M
Installed size: 3.1 M
Is this ok [y/N]: y
Downloading Packages:
openssl-devel-1.0.2k-1.fc25.x86_64.rpm          580 kB/s | 1.5 MB     00:02    
--------------------------------------------------------------------------------
Total                                           394 kB/s | 1.5 MB     00:03     
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
  Installing  : openssl-devel-1:1.0.2k-1.fc25.x86_64                        1/1 
  Verifying   : openssl-devel-1:1.0.2k-1.fc25.x86_64                        1/1 

Installed:
  openssl-devel.x86_64 1:1.0.2k-1.fc25                                          

Complete!

Try to run again the first command:

pip freeze --local | grep -v '^\-e' | cut -d = -f 1  | xargs -n1 pip install -U

See the first result of list outdated python modules:

[root@localhost mythcat]# pip list --outdated --format=freeze
CCColUtils==1.4
cryptography==1.5.3
evdev==0.6.1
fedmsg==0.18.2
ipykernel==4.5.2
M2Crypto==0.25.1
matplotlib==1.5.2rc2
mercurial==3.8.1
mysqlclient==1.3.7
psutil==4.3.0
pycryptopp==0.6.0.1206569328141510525648634803928199668821045408958
pyopencl==2015.2
pyOpenSSL==16.0.0
pyxattr==0.5.3
requests-kerberos==0.10.0
service-identity==14.0.0
Sphinx==1.5.3
SQLAlchemy==1.1.6
Tempita==0.5.1
tornado==4.4.2
Twisted==16.3.0
txZMQ==0.7.4

After this steps the result is this:

[root@localhost mythcat]# pip list --outdated --format=freeze
mysqlclient==1.3.7
pyopencl==2015.2
pyxattr==0.5.3

I will fix this next time.

The GUI for Clam antivirus - clamtk .

Today I will show you how to use a GUI for clam antivirus named clamtk.
The ClamTk is a graphical front-end for ClamAV using Perl and Gtk libraries.

[root@localhost mythcat]# dnf search clamtk
Last metadata expiration check: 1:24:49 ago on Tue Apr 18 17:01:00 2017.
============================= N/S Matched: clamtk ==============================
clamtk.noarch : Easy to use graphical user interface for Clam anti virus

First, you need to install it, see all packages need by this GUI:

[root@localhost mythcat]# dnf install clamtk.noarch 
Last metadata expiration check: 1:31:00 ago on Tue Apr 18 17:01:00 2017.
Dependencies resolved.
================================================================================
 Package                     Arch       Version               Repository   Size
================================================================================
Installing:
 clamtk                      noarch     5.24-1.fc25           updates     218 k
 perl-Cairo                  x86_64     1.106-3.fc25          fedora      125 k
 perl-File-Listing           noarch     6.04-13.fc25          fedora       17 k
 perl-Glib                   x86_64     1.321-2.fc25          fedora      364 k
 perl-Gtk2                   x86_64     1.2498-3.fc25         fedora      1.8 M
 perl-HTTP-Cookies           noarch     6.01-13.fc25          fedora       29 k
 perl-HTTP-Negotiate         noarch     6.01-13.fc25          fedora       21 k
 perl-JSON                   noarch     2.90-7.fc25           fedora       98 k
 perl-LWP-Protocol-https     noarch     6.07-1.fc25           updates      16 k
 perl-Locale-gettext         x86_64     1.07-4.fc25           fedora       26 k
 perl-NTLM                   noarch     1.09-13.fc25          fedora       23 k
 perl-Net-HTTP               noarch     6.13-1.fc25           updates      41 k
 perl-Pango                  x86_64     1.227-3.fc25          fedora      190 k
 perl-Test-Simple            noarch     1.302062-1.fc25       fedora      410 k
 perl-Text-CSV               noarch     1.91-4.fc25           updates     103 k
 perl-Time-Piece             x86_64     1.31-385.fc25         updates      88 k
 perl-WWW-RobotRules         noarch     6.02-14.fc25          fedora       22 k
 perl-libwww-perl            noarch     6.15-3.fc25           fedora      208 k

Transaction Summary
================================================================================
Install  18 Packages

Total download size: 3.7 M
Installed size: 10 M
Is this ok [y/N]: y
Downloading Packages:
(1/18): clamtk-5.24-1.fc25.noarch.rpm           517 kB/s | 218 kB     00:00    
(2/18): perl-Glib-1.321-2.fc25.x86_64.rpm       662 kB/s | 364 kB     00:00    
(3/18): perl-Locale-gettext-1.07-4.fc25.x86_64. 296 kB/s |  26 kB     00:00    
(4/18): perl-Gtk2-1.2498-3.fc25.x86_64.rpm      2.3 MB/s | 1.8 MB     00:00    
(5/18): perl-libwww-perl-6.15-3.fc25.noarch.rpm 1.4 MB/s | 208 kB     00:00    
(6/18): perl-JSON-2.90-7.fc25.noarch.rpm        181 kB/s |  98 kB     00:00    
(7/18): perl-Cairo-1.106-3.fc25.x86_64.rpm      439 kB/s | 125 kB     00:00    
(8/18): perl-Pango-1.227-3.fc25.x86_64.rpm      1.7 MB/s | 190 kB     00:00    
(9/18): perl-File-Listing-6.04-13.fc25.noarch.r 204 kB/s |  17 kB     00:00    
(10/18): perl-HTTP-Cookies-6.01-13.fc25.noarch. 375 kB/s |  29 kB     00:00    
(11/18): perl-HTTP-Negotiate-6.01-13.fc25.noarc 250 kB/s |  21 kB     00:00    
(12/18): perl-Test-Simple-1.302062-1.fc25.noarc 1.5 MB/s | 410 kB     00:00    
(13/18): perl-NTLM-1.09-13.fc25.noarch.rpm      160 kB/s |  23 kB     00:00    
(14/18): perl-WWW-RobotRules-6.02-14.fc25.noarc 168 kB/s |  22 kB     00:00    
(15/18): perl-Net-HTTP-6.13-1.fc25.noarch.rpm   315 kB/s |  41 kB     00:00    
(16/18): perl-Time-Piece-1.31-385.fc25.x86_64.r 638 kB/s |  88 kB     00:00    
(17/18): perl-LWP-Protocol-https-6.07-1.fc25.no  77 kB/s |  16 kB     00:00    
(18/18): perl-Text-CSV-1.91-4.fc25.noarch.rpm   297 kB/s | 103 kB     00:00    
--------------------------------------------------------------------------------
Total                                           1.3 MB/s | 3.7 MB     00:02     
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
  Installing  : perl-Glib-1.321-2.fc25.x86_64                              1/18 
  Installing  : perl-Net-HTTP-6.13-1.fc25.noarch                           2/18 
  Installing  : perl-Cairo-1.106-3.fc25.x86_64                             3/18 
  Installing  : perl-Pango-1.227-3.fc25.x86_64                             4/18 
  Installing  : perl-Time-Piece-1.31-385.fc25.x86_64                       5/18 
  Installing  : perl-Text-CSV-1.91-4.fc25.noarch                           6/18 
  Installing  : perl-WWW-RobotRules-6.02-14.fc25.noarch                    7/18 
  Installing  : perl-NTLM-1.09-13.fc25.noarch                              8/18 
  Installing  : perl-HTTP-Negotiate-6.01-13.fc25.noarch                    9/18 
  Installing  : perl-HTTP-Cookies-6.01-13.fc25.noarch                     10/18 
  Installing  : perl-File-Listing-6.04-13.fc25.noarch                     11/18 
  Installing  : perl-libwww-perl-6.15-3.fc25.noarch                       12/18 
  Installing  : perl-LWP-Protocol-https-6.07-1.fc25.noarch                13/18 
  Installing  : perl-Test-Simple-1.302062-1.fc25.noarch                   14/18 
  Installing  : perl-Gtk2-1.2498-3.fc25.x86_64                            15/18 
  Installing  : perl-Locale-gettext-1.07-4.fc25.x86_64                    16/18 
  Installing  : perl-JSON-2.90-7.fc25.noarch                              17/18 
  Installing  : clamtk-5.24-1.fc25.noarch                                 18/18 
  Verifying   : clamtk-5.24-1.fc25.noarch                                  1/18 
  Verifying   : perl-Glib-1.321-2.fc25.x86_64                              2/18 
  Verifying   : perl-Gtk2-1.2498-3.fc25.x86_64                             3/18 
  Verifying   : perl-JSON-2.90-7.fc25.noarch                               4/18 
  Verifying   : perl-Locale-gettext-1.07-4.fc25.x86_64                     5/18 
  Verifying   : perl-libwww-perl-6.15-3.fc25.noarch                        6/18 
  Verifying   : perl-Cairo-1.106-3.fc25.x86_64                             7/18 
  Verifying   : perl-Pango-1.227-3.fc25.x86_64                             8/18 
  Verifying   : perl-Test-Simple-1.302062-1.fc25.noarch                    9/18 
  Verifying   : perl-File-Listing-6.04-13.fc25.noarch                     10/18 
  Verifying   : perl-HTTP-Cookies-6.01-13.fc25.noarch                     11/18 
  Verifying   : perl-HTTP-Negotiate-6.01-13.fc25.noarch                   12/18 
  Verifying   : perl-NTLM-1.09-13.fc25.noarch                             13/18 
  Verifying   : perl-WWW-RobotRules-6.02-14.fc25.noarch                   14/18 
  Verifying   : perl-Net-HTTP-6.13-1.fc25.noarch                          15/18 
  Verifying   : perl-LWP-Protocol-https-6.07-1.fc25.noarch                16/18 
  Verifying   : perl-Text-CSV-1.91-4.fc25.noarch                          17/18 
  Verifying   : perl-Time-Piece-1.31-385.fc25.x86_64                      18/18 

Installed:
  clamtk.noarch 5.24-1.fc25                                                     
  perl-Cairo.x86_64 1.106-3.fc25                                                
  perl-File-Listing.noarch 6.04-13.fc25                                         
  perl-Glib.x86_64 1.321-2.fc25                                                 
  perl-Gtk2.x86_64 1.2498-3.fc25                                                
  perl-HTTP-Cookies.noarch 6.01-13.fc25                                         
  perl-HTTP-Negotiate.noarch 6.01-13.fc25                                       
  perl-JSON.noarch 2.90-7.fc25                                                  
  perl-LWP-Protocol-https.noarch 6.07-1.fc25                                    
  perl-Locale-gettext.x86_64 1.07-4.fc25                                        
  perl-NTLM.noarch 1.09-13.fc25                                                 
  perl-Net-HTTP.noarch 6.13-1.fc25                                              
  perl-Pango.x86_64 1.227-3.fc25                                                
  perl-Test-Simple.noarch 1.302062-1.fc25                                       
  perl-Text-CSV.noarch 1.91-4.fc25                                              
  perl-Time-Piece.x86_64 1.31-385.fc25                                          
  perl-WWW-RobotRules.noarch 6.02-14.fc25                                       
  perl-libwww-perl.noarch 6.15-3.fc25                                           

Complete!

By using the mouse with a double-click you can make changes into anti-virus settings.
The first step when opening ClamTK GUI is to select "Update Assistant".
You can choose "I would like to update signatures myself".
You should go back to the home screen of ClamTK and click "Settings"
Also, you can use this GUI to scan, update and analysis your operating system.

Fedora 25 : The YARA tool for Linux security - part 001.

The YARA tool is a multi-platform program running on Windows, Linux and Mac OS X.
The YARA is designed to help malware researchers identify and classify malware samples.
It’s been called for security researchers and everyone else.
Yara provides an easy and effective way to write custom rules based on strings or byte sequences and allows you to make your own detection tools.
You can create descriptions of malware families based on textual or binary patterns or whatever you want to describe.
This descriptions or rules consists of a set of strings and a boolean expression which determine its logic.
The official website can be found here.
The First you need to install the yara tool under your Linux OS.
I used Fedora 25 distro.

[root@localhost mythcat]# dnf install yara
Last metadata expiration check: 0:49:37 ago on Sun Apr 16 22:23:14 2017.
Dependencies resolved.
================================================================================
 Package      Arch           Version              Repository               Size
================================================================================
Installing:
 yara         x86_64         3.5.0-7.fc25         updates-testing         191 k

Transaction Summary
================================================================================
Install  1 Package

Total download size: 191 k
Installed size: 861 k
Is this ok [y/N]: y
Downloading Packages:
yara-3.5.0-7.fc25.x86_64.rpm                    171 kB/s | 191 kB     00:01    
--------------------------------------------------------------------------------
Total                                            92 kB/s | 191 kB     00:02     
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
  Installing  : yara-3.5.0-7.fc25.x86_64                                    1/1 
  Verifying   : yara-3.5.0-7.fc25.x86_64                                    1/1 

Installed:
  yara.x86_64 3.5.0-7.fc25                                                      

Complete!

Let test it with the basic command:

[mythcat@localhost ~]$ yara
yara: wrong number of arguments
Usage: yara [OPTION]... RULES_FILE FILE | DIR | PID

Try `--help` for more options
[mythcat@localhost ~]$ yara --help
YARA 3.5.0, the pattern matching swiss army knife.
Usage: yara [OPTION]... RULES_FILE FILE | DIR | PID

Mandatory arguments to long options are mandatory for short options too.

  -t,  --tag=TAG                   print only rules tagged as TAG
  -i,  --identifier=IDENTIFIER     print only rules named IDENTIFIER
  -n,  --negate                    print only not satisfied rules (negate)
  -D,  --print-module-data         print module data
  -g,  --print-tags                print tags
  -m,  --print-meta                print metadata
  -s,  --print-strings             print matching strings
  -e,  --print-namespace           print rules' namespace
  -p,  --threads=NUMBER            use the specified NUMBER of threads to scan a directory
  -l,  --max-rules=NUMBER          abort scanning after matching a NUMBER of rules
  -d VAR=VALUE                     define external variable
  -x MODULE=FILE                   pass FILE's content as extra data to MODULE
  -a,  --timeout=SECONDS           abort scanning after the given number of SECONDS
  -k,  --stack-size=SLOTS          set maximum stack size (default=16384)
  -r,  --recursive                 recursively search directories
  -f,  --fast-scan                 fast matching mode
  -w,  --no-warnings               disable warnings
  -v,  --version                   show version information
  -h,  --help                      show this help and exit

Send bug reports and suggestions to: vmalvarez@virustotal.com .

When you use YARA you can use:

• modules - like extensions to YARA’s core functionality; 
• external variables; 
• including files; 

The YARA use rules and this rules are: global rules, private rules, tags and metadata.
The base of the syntax of a YARA rule set is this:

rule RuleName  
{
    strings:
    $test_string1= "Testing"
    $test_string2= {C6 45 ?? ??}
    condition:
    $test_string1 or $test_string2
}

The words strings and Conditions are two important keywords: strings and condition. The rule work with strings and this strings are the unique values to search for, while condition specifies your detection criteria. Some example with con:

all of them       /* all strings in the rule */
any of them       /* any string in the rule */
all of ($a*)      /* all strings whose identifier starts by $a */
any of ($a,$b,$c) /* any of $a, $b or $c */
1 of ($*)         /* same that "any of them" */

You can include also the meta keyword, see:

rule RuleName  
{
   meta:
      author = "Catalin George Festila - rule 001 "
      description = "tell something to the computer"
   strings:
   $test_string1= "first step "
...

The metadata can be referenced using the arg –m option at the command line.

You can add comments to your YARA rules just as if it was a C source file because rules have a syntax that resembles the C language.

The whiptail tool .

This command let you deal with many display dialog boxes from shell scripts.
The command is named whiptail and you can read and see simple examples with this command here.

Note: --infobox is almost useless in an xterm, because whiptail writes to the other screen xterm makes available but you can use the --msgbox

The tutorial of this day will show you how to put the text from a text file to the screen.
First, you need a text file with a size of your shell screen and this will be used by this command.
For example, I used this text from Wikipedia into my text file named greeting.txt, see content :

The Paschal Greeting, also known as the Easter Acclamation, is an Easter custom among Eastern Orthodox, Oriental Orthodox, and Eastern Catholic Christians. Instead of "hello" or its equivalent, one is to greet another person with "Christ is Risen!" or "The Lord is Risen!", and the response is "Truly, He is Risen," "Indeed, He is Risen," or "He is Risen Indeed" - compare Matthew 27:64, Matthew 28:6 7, Mark 16:6, Luke 24:6, Luke 24:34 In some cultures, such as in Russia and Serbia, it is also customary to exchange a triple kiss of peace on the alternating cheeks after the greeting. Similar responses are also used in the liturgies of other Christian churches, but not so much as general greetings.

To use the whiptail command just use this into your shell:

[mythcat@localhost ~]$ whiptail --textbox  /dev/stdin  19 59  <<<"$(cat greeting.txt)"

The output of this command can be seen into next image:

Linux: tools to scan a Linux server for malware and rootkits.

This tools are: chkrootkit, rkhunter, fuser and ISPProtect. All of this tools can be install under Fedora 25 with dnf tool. First tool is chkrootkit is a classic rootkit scanner. It checks your server for suspicious rootkit processes and checks for a list of known rootkit files.

[root@localhost mythcat]# chkrootkit
ROOTDIR is `/'
Checking `amd'... not found
Checking `basename'... not infected
Checking `biff'... not found
Checking `chfn'... not infected
Checking `chsh'... not infected
Checking `cron'... not infected
Checking `crontab'... not infected
Checking `date'... not infected
Checking `du'... not infected
Checking `dirname'... not infected
Checking `echo'... not infected
...

The Rootkit Hunter named rkhunter is a Unix-based tool that scans for rootkits, backdoors and possible local exploits.

[root@localhost mythcat]# rkhunter --update
[ Rootkit Hunter version 1.4.2 ]

Checking rkhunter data files...
  Checking file mirrors.dat                                  [ No update ]
  Checking file programs_bad.dat                             [ No update ]
  Checking file backdoorports.dat                            [ No update ]
  Checking file suspscan.dat                                 [ No update ]
  Checking file i18n/cn                                      [ No update ]
  Checking file i18n/de                                      [ No update ]
  Checking file i18n/en                                      [ No update ]
  Checking file i18n/tr                                      [ No update ]
  Checking file i18n/tr.utf8                                 [ No update ]
  Checking file i18n/zh                                      [ No update ]
  Checking file i18n/zh.utf8                                 [ No update ]
[root@localhost mythcat]# rkhunter --propupd
[ Rootkit Hunter version 1.4.2 ]
File created: searched for 172 files, found 136
[root@localhost mythcat]# rkhunter -c --enable all --disable none
[ Rootkit Hunter version 1.4.2 ]

Checking system commands...

  Performing 'strings' command checks
    Checking 'strings' command                               [ OK ]

  Performing 'shared libraries' checks
    Checking for preloading variables                        [ None found ]
    Checking for preloaded libraries                         [ None found ]
    Checking LD_LIBRARY_PATH variable                        [ Not found ]

  Performing file properties checks
    Checking for prerequisites                               [ OK ]
    /usr/bin/awk                                             [ OK ]
    /usr/bin/basename                                        [ OK ]
    /usr/bin/bash                                            [ OK ]
    /usr/bin/cat                                             [ OK ]
    /usr/bin/chattr                                          [ OK ]
    /usr/bin/chmod                                           [ OK ]
    /usr/bin/chown                                           [ OK ]
    /usr/bin/cp                                              [ OK ]
...

Another tool is fuser

[root@localhost mythcat]# fuser -vn tcp 5222
...

The output of this command let you to see the recall of anything on your machine that should be listening on tcp port 5222.

[root@localhost mythcat]# fuser -vn tcp 19635
...

This output indicates that there is a process named "foo" running with PID number and listening on port 19635. The last tool is ISPProtect. ISPProtect is a malware scanner for web servers, it scans for malware in website files and CMS systems like Wordpress, Joomla, Drupal

The journalctl command.

This is a good Linux command for Linux maintenance.
The first step is to read the documentation:

[root@localhost mythcat]# man journalctl
JOURNALCTL(1)                     journalctl                     JOURNALCTL(1)

NAME
       journalctl - Query the systemd journal

SYNOPSIS
       journalctl [OPTIONS...] [MATCHES...]

DESCRIPTION
       journalctl may be used to query the contents of the systemd(1) journal
       as written by systemd-journald.service(8).

       If called without parameters, it will show the full contents of the
       journal, starting with the oldest entry collected.

       If one or more match arguments are passed, the output is filtered
       accordingly. A match is in the format "FIELD=VALUE", e.g.
       "_SYSTEMD_UNIT=httpd.service", referring to the components of a
       structured journal entry. See systemd.journal-fields(7) for a list of
       well-known fields. If multiple matches are specified matching different
       fields, the log entries are filtered by both, i.e. the resulting output
       will show only entries matching all the specified matches of this kind.
       If two matches apply to the same field, then they are automatically
       matched as alternatives, i.e. the resulting output will show entries
       matching any of the specified matches for the same field. Finally, the
       character "+" may appear as a separate word between other terms on the
       command line. This causes all matches before and after to be combined
       in a disjunction (i.e. logical OR).
       ...

The self-maintenance method is to vacuum the logs.
This helps you with free space into your Linux OS.
For example, I got 3 Gigabytes of data in just 3 days.

# journalctl --vacuum-time=3d

Vacuuming done, freed 3.7G of archived journals on disk. To clean up this you can use the command into several ways:

• by time

journalctl --vacuum-time=2d

• retain only the past 500 MB

journalctl --vacuum-size=500M

As you know: The is an init system used in Linux distributions to bootstrap the user space and manage all processes subsequently. The journald daemon handles all of the messages produced by the kernel, initrd, services, etc. You can use the journalctl utility, which can be used to access and manipulate the data held within the journal. Let's start with some examples: How to see the configuration file for this process:

[root@localhost mythcat]# cat /etc/systemd/journald.conf

Also, you can see the status of this service:

[root@localhost mythcat]# systemctl status  systemd-journald
● systemd-journald.service - Journal Service
   Loaded: loaded (/usr/lib/systemd/system/systemd-journald.service; static; vendor preset: disabled)
   Active: active (running) since Tue 2017-03-28 09:12:20 EEST; 1h 8min ago
     Docs: man:systemd-journald.service(8)
           man:journald.conf(5)
 Main PID: 803 (systemd-journal)
   Status: "Processing requests..."
    Tasks: 1 (limit: 4915)
   CGroup: /system.slice/systemd-journald.service
           └─803 /usr/lib/systemd/systemd-journald

Mar 28 09:12:20 localhost.localdomain systemd-journald[803]: Runtime journal (/run/log/journal/) is 8.0M,
max 371.5M, 363.5M free.
Mar 28 09:12:20 localhost.localdomain systemd-journald[803]: Journal started
Mar 28 09:12:22 localhost.localdomain systemd-journald[803]: System journal (/var/log/journal/) is 3.9G,
max 4.0G, 23.8M free.
Mar 28 09:12:23 localhost.localdomain systemd-journald[803]: Time spent on flushing to /var is 915.454ms

I hope this article will help you with Linux maintenance

Measure the charging with Ampere.

This android application let you to know more about your battery.
Just use it to measure the charging and discharging current of your battery.
-
Or, you can also use a hardware device and Fedora 25 to have a great life.

Fedora 25: First test with clamav antivirus.

This is a short tutorial about how to use ClamAV antivirus on Fedora 25.
First, you need to install it with this commands:

[root@localhost mythcat]# dnf install clamav.x86_64 
...

[root@localhost mythcat]# dnf install clamav-update.x86_64
...

Make settings into your /etc/freshclam.conf file. I used awk tool to show you my settings from /etc/freshclam.conf:

[root@localhost mythcat]# awk -F: '/^[^#]/ { print $1 }' /etc/freshclam.conf | uniq 

DatabaseDirectory /var/lib/clamav
UpdateLogFile /var/log/freshclam.log
LogFileMaxSize 2M
LogTime yes
LogVerbose yes
LogSyslog yes
LogFacility LOG_MAIL
LogRotate yes
DatabaseOwner clamupdate
DNSDatabaseInfo current.cvd.clamav.net
DatabaseMirror database.clamav.net
MaxAttempts 5
ScriptedUpdates yes
DetectionStatsCountry country-code
SafeBrowsing yes

Update the ClamAV antivirus with :

[root@localhost mythcat]# /usr/bin/freshclam
ClamAV update process started at Wed Mar 15 13:42:07 2017
main.cvd is up to date (version: 57, sigs: 4218790, f-level: 60, builder: amishhammer)
WARNING: getfile: daily-21724.cdiff not found on database.clamav.net (IP: 195.30.97.3)
WARNING: getpatch: Can't download daily-21724.cdiff from database.clamav.net
Trying host database.clamav.net (212.7.0.71)...
nonblock_connect: connect timing out (30 secs)
Can't connect to port 80 of host database.clamav.net (IP: 212.7.0.71)
WARNING: getpatch: Can't download daily-21724.cdiff from database.clamav.net
WARNING: getpatch: Can't download daily-21724.cdiff from database.clamav.net
WARNING: getpatch: Can't download daily-21724.cdiff from database.clamav.net
WARNING: getpatch: Can't download daily-21724.cdiff from database.clamav.net
WARNING: Incremental update failed, trying to download daily.cvd
Downloading daily.cvd [100%]
daily.cvd updated (version: 23205, sigs: 1789155, f-level: 63, builder: neo)
Downloading safebrowsing.cvd [100%]
safebrowsing.cvd updated (version: 45693, sigs: 2756150, f-level: 63, builder: google)
Downloading bytecode-279.cdiff [100%]
Downloading bytecode-280.cdiff [100%]
Downloading bytecode-281.cdiff [100%]
Downloading bytecode-282.cdiff [100%]
Downloading bytecode-283.cdiff [100%]
Downloading bytecode-284.cdiff [100%]
Downloading bytecode-285.cdiff [100%]
Downloading bytecode-286.cdiff [100%]
Downloading bytecode-287.cdiff [100%]
Downloading bytecode-288.cdiff [100%]
Downloading bytecode-289.cdiff [100%]
Downloading bytecode-290.cdiff [100%]
Downloading bytecode-291.cdiff [100%]
bytecode.cld updated (version: 291, sigs: 55, f-level: 63, builder: neo)
Database updated (8764150 signatures) from database.clamav.net (IP: 157.25.5.183)

Now you can run it on Fedora 25 folder with this.

[root@localhost mythcat]# clamscan 
/home/mythcat/.bash_logout: OK
/home/mythcat/.bash_profile: OK
...
----------- SCAN SUMMARY -----------
Known viruses: 8758441
Engine version: 0.99.2
Scanned directories: 1
Scanned files: 54
Infected files: 0
Data scanned: 71.80 MB
Data read: 189.96 MB (ratio 0.38:1)
Time: 13.968 sec (0 m 13 s)

This tool comes with many options and features for Fedora workstations and server. Just read the documentation and make your changes. To check all files on the computer, but only display infected files and ring a bell when found:

clamscan -r --bell -i / 

To check files in the all users home directories:

clamscan -r /home 

If you got this error:

LibClamAV Warning: fmap_readpage: pread fail: ... 

Then this comes from sysfs and is a virtual file system provided by the Linux kernel and need to be excluded with this arg:

--exclude-dir="^/sys"

--exclude-dir=^/sys  --exclude-dir=^/dev --exclude-dir=^/proc 

My result of scan ( the file FOUND is not a virus) :

/home/mythcat/devil-linux-1.8.0-rc2-x86_64/install-on-usb.exe: Win.Trojan.Delfiles-17 FOUND

----------- SCAN SUMMARY -----------
Known viruses: 9042471
Engine version: 0.99.2
Scanned directories: 98653
Scanned files: 570740
Infected files: 1
Data scanned: 29750.14 MB
Data read: 48591.70 MB (ratio 0.61:1)
Time: 3819.053 sec (63 m 39 s)

QEMU - Devil Linux on Fedora 25.

QEMU (short for Quick Emulator) is a free and open-source hosted hypervisor that performs hardware virtualization QEMU is a hosted virtual machine monitor. You can install this software using dnf tool.

dnf install qemu.x86_64 

You can use any iso image from internet to run and test your distro linux. Just use this command:
I tested with Devil Linux iso without network ( the main reason was the settings of Devil Linux distro).

qemu-system-x86_64 -boot d -cdrom ~/devil-linux-1.8.0-rc2-x86_64/bootcd.iso --enable-kvm -m 2048
 -netdev user,id=user.0

Some args of qemu tool:
- qemu-system-x86_64 is the option for x86 architecture (64 bit);
- boot and -d set options for booting and debug;
- the -cdrom option set the iso file path and file;
- the --enable-kvm enable Kernel Virtual Machine;
- the -m 2048 set memory;
- the -netdev user,id=user.0 that tells us about qemu to use the user mode network stack which requires no administrator privilege to run;  
About QEMU VLAN.
QEMU networking uses a networking technology that is like VLAN. The QEMU forward packets to guest operating systems that are on the same VLAN. Examples with qemu-kvm options:

-net nic,model=virtio,vlan=0,macaddr=00:16:3e:00:01:01 
-net tap,vlan=0,script=/root/ifup-br0,downscript=/root/ifdown-br0 
-net nic,model=virtio,vlan=1,macaddr=00:16:3e:00:01:02 
-net tap,vlan=1,script=/root/ifup-br1,downscript=/root/ifdown-br1

- net nic command defines a network adapter in the guest operating system. - net tap command defines how QEMU configures the host. You can disabling networking entirely:

-net none

News: WikiLeaks begins its new series of leaks on the U.S. Central Intelligence Agency.

This is a old news and comes from WikiLeaks how to start one new series of leaks on the U.S. Central Intelligence Agency.
For me is another way to show bugs to people.
The article can be found here:
Some software come with new updates to fix bugs - like notepad, see article: Notepad++ 7.3.3 update fixe.

Fedora 25: Enable gnome notifications Fedmsg and Openweather.

This tutorial is about gnome environment and notifications.
If you want to see notifications about your work and account under Fedora distro or just to see the weather then you need to deal with this tools.
Take a look to your gnome version and shell version:

[mythcat@localhost ~]$ gnome-about --gnome-version 
Version: 2.32.0
Distributor: Red Hat, Inc
Build Date: 02/04/2016
[mythcat@localhost ~]$ gnome-shell --version 
GNOME Shell 3.22.3

Use the dnf install tool and get this packages:

gnome-weather.noarch : A weather application for GNOME
gnome-weather-tests.noarch : Tests for the gnome-weather package
gnome-shell-extension-openweather.noarch : Display weather information from many
gnome-shell-extension-apps-menu.noarch : Application menu for GNOME Shell
gnome-shell.x86_64 : Window management and application launching for GNOME
gnome-shell-extension-common.noarch : Files common to GNOME Shell Extensions
gnome-tweak-tool.noarch : A tool to customize advanced GNOME 3 options

Use this command to make settings:

[mythcat@localhost ~]$ gnome-tweak-tool

You will see a window with options for enable Fedmsg and Openweather notifications.
After select on option then just use right click to make settings for each extension.

Fedora 25: Install the ffmpeg tools .

Install from web the repos rpmfusion using root account:

# dnf install http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm
[root@localhost]# dnf install http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-$(rpm -E %fedora).noarch.rpm

Now with enable the repo all rpmfusion list ffmpeg:

# yum --enablerepo=rpmfusion-* list ffmpeg
Redirecting to '/usr/bin/dnf --enablerepo=rpmfusion-* list ffmpeg' (see 'man yum2dnf')

RPM Fusion for Fedora 25 - Free - Test Updates 1.3 kB/s | 1.9 kB     00:01    
RPM Fusion for Fedora 25 - Nonfree - Updates S 4.8 kB/s | 7.0 kB     00:01    
RPM Fusion for Fedora 25 - Free - Updates Debu 185 kB/s | 331 kB     00:01    
RPM Fusion for Fedora 25 - Nonfree - Test Upda 1.7 kB/s | 2.7 kB     00:01    
RPM Fusion for Fedora Rawhide - Nonfree         91 kB/s | 157 kB     00:01    
RPM Fusion for Fedora Rawhide - Free - Debug   280 kB/s | 521 kB     00:01    
RPM Fusion for Fedora 25 - Free - Source        58 kB/s |  95 kB     00:01    
RPM Fusion for Fedora 25 - Free - Test Updates 9.7 kB/s |  16 kB     00:01    
RPM Fusion for Fedora 25 - Nonfree - Updates D 3.8 kB/s | 5.6 kB     00:01    
RPM Fusion for Fedora Rawhide - Nonfree - Sour  24 kB/s |  37 kB     00:01    
RPM Fusion for Fedora 25 - Free - Updates Sour 143 kB/s |  30 kB     00:00    
RPM Fusion for Fedora 25 - Nonfree             525 kB/s | 144 kB     00:00    
RPM Fusion for Fedora Rawhide - Free           1.1 MB/s | 531 kB     00:00    
RPM Fusion for Fedora 25 - Free - Test Updates  23 kB/s | 3.6 kB     00:00    
RPM Fusion for Fedora 25 - Nonfree - Updates    13 kB/s |  19 kB     00:01    
RPM Fusion for Fedora Rawhide - Free - Source   58 kB/s |  97 kB     00:01    
RPM Fusion for Fedora 25 - Free - Debug        879 kB/s | 380 kB     00:00    
RPM Fusion for Fedora 25 - Nonfree - Debug      41 kB/s |  69 kB     00:01    
RPM Fusion for Fedora 25 - Nonfree - Test Upda 1.7 kB/s | 2.6 kB     00:01    
RPM Fusion for Fedora 25 - Nonfree - Source     22 kB/s |  34 kB     00:01    
RPM Fusion for Fedora 25 - Nonfree - Test Upda 5.4 kB/s | 8.5 kB     00:01    
RPM Fusion for Fedora Rawhide - Nonfree - Debu 241 kB/s |  70 kB     00:00    
RPM Fusion for Fedora 25 - Free - Updates      154 kB/s | 254 kB     00:01    
RPM Fusion for Fedora 25 - Free                288 kB/s | 515 kB     00:01    
Available Packages
ffmpeg.src               3.2.4-1.fc26             rpmfusion-free-rawhide-source
ffmpeg.x86_64            3.2.4-1.fc26             rpmfusion-free-rawhide

Then install ffmpeg:

[root@localhost]# yum --enablerepo=rpmfusion-* install ffmpeg.x86_64
Redirecting to '/usr/bin/dnf --enablerepo=rpmfusion-* install ffmpeg.x86_64' (see 'man yum2dnf')

Last metadata expiration check: 0:00:26 ago on Tue Mar  7 23:40:51 2017.
Dependencies resolved.
===============================================================================
 Package      Arch   Version                      Repository              Size
===============================================================================
Installing:
 ffmpeg       x86_64 3.2.4-1.fc26                 rpmfusion-free-rawhide 1.5 M
 ffmpeg-libs  x86_64 3.2.4-1.fc26                 rpmfusion-free-rawhide 6.2 M
 fribidi      x86_64 0.19.7-2.fc24                fedora                  70 k
 lame-libs    x86_64 3.99.5-6.fc26                rpmfusion-free-rawhide 344 k
 libass       x86_64 0.13.4-1.fc25                fedora                  95 k
 libavdevice  x86_64 3.2.4-1.fc26                 rpmfusion-free-rawhide  83 k
 libmfx       x86_64 1.19-1.20170114gita5ba231.fc25
                                                  updates                 33 k
 libva        x86_64 1.7.3-3.fc25                 updates                 89 k
 ocl-icd      x86_64 2.2.11-1.fc25                updates                 46 k
 opencore-amr x86_64 0.1.3-4.fc24                 rpmfusion-free-rawhide 176 k
 schroedinger x86_64 1.0.11-10.fc24               fedora                 325 k
 vo-amrwbenc  x86_64 0.1.3-1.fc24                 rpmfusion-free-rawhide  76 k
 x264-libs    x86_64 0.148-15.20170121git97eaef2.fc26
                                                  rpmfusion-free-rawhide 574 k
 x265-libs    x86_64 2.2-1.fc26                   rpmfusion-free-rawhide 586 k
 xvidcore     x86_64 1.3.4-2.fc24                 rpmfusion-free-rawhide 262 k

Transaction Summary
===============================================================================
Install  15 Packages

Total download size: 10 M
Installed size: 28 M
Is this ok [y/N]: y
Downloading Packages:
(1/15): x265-libs-2.2-1.fc26.x86_64.rpm        780 kB/s | 586 kB     00:00    
(2/15): ffmpeg-3.2.4-1.fc26.x86_64.rpm         1.6 MB/s | 1.5 MB     00:00    
(3/15): libass-0.13.4-1.fc25.x86_64.rpm        294 kB/s |  95 kB     00:00    
(4/15): fribidi-0.19.7-2.fc24.x86_64.rpm       137 kB/s |  70 kB     00:00    
(5/15): libmfx-1.19-1.20170114gita5ba231.fc25. 418 kB/s |  33 kB     00:00    
(6/15): libva-1.7.3-3.fc25.x86_64.rpm          915 kB/s |  89 kB     00:00    
(7/15): schroedinger-1.0.11-10.fc24.x86_64.rpm 1.3 MB/s | 325 kB     00:00    
(8/15): ocl-icd-2.2.11-1.fc25.x86_64.rpm       401 kB/s |  46 kB     00:00    
(9/15): ffmpeg-libs-3.2.4-1.fc26.x86_64.rpm    3.8 MB/s | 6.2 MB     00:01    
(10/15): lame-libs-3.99.5-6.fc26.x86_64.rpm    2.1 MB/s | 344 kB     00:00    
(11/15): opencore-amr-0.1.3-4.fc24.x86_64.rpm  1.1 MB/s | 176 kB     00:00    
(12/15): vo-amrwbenc-0.1.3-1.fc24.x86_64.rpm   656 kB/s |  76 kB     00:00    
(13/15): xvidcore-1.3.4-2.fc24.x86_64.rpm      1.9 MB/s | 262 kB     00:00    
(14/15): x264-libs-0.148-15.20170121git97eaef2 2.7 MB/s | 574 kB     00:00    
(15/15): libavdevice-3.2.4-1.fc26.x86_64.rpm   694 kB/s |  83 kB     00:00    
-------------------------------------------------------------------------------
Total                                          2.2 MB/s |  10 MB     00:04     
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
  Installing  : libva-1.7.3-3.fc25.x86_64                                 1/15 
  Installing  : libmfx-1.19-1.20170114gita5ba231.fc25.x86_64              2/15 
  Installing  : ocl-icd-2.2.11-1.fc25.x86_64                              3/15 
  Installing  : fribidi-0.19.7-2.fc24.x86_64                              4/15 
  Installing  : libass-0.13.4-1.fc25.x86_64                               5/15 
  Installing  : xvidcore-1.3.4-2.fc24.x86_64                              6/15 
  Installing  : x264-libs-0.148-15.20170121git97eaef2.fc26.x86_64         7/15 
  Installing  : vo-amrwbenc-0.1.3-1.fc24.x86_64                           8/15 
  Installing  : opencore-amr-0.1.3-4.fc24.x86_64                          9/15 
  Installing  : lame-libs-3.99.5-6.fc26.x86_64                           10/15 
  Installing  : schroedinger-1.0.11-10.fc24.x86_64                       11/15 
  Installing  : x265-libs-2.2-1.fc26.x86_64                              12/15 
  Installing  : ffmpeg-libs-3.2.4-1.fc26.x86_64                          13/15 
  Installing  : libavdevice-3.2.4-1.fc26.x86_64                          14/15 
  Installing  : ffmpeg-3.2.4-1.fc26.x86_64                               15/15 
  Verifying   : ffmpeg-3.2.4-1.fc26.x86_64                                1/15 
  Verifying   : ffmpeg-libs-3.2.4-1.fc26.x86_64                           2/15 
  Verifying   : x265-libs-2.2-1.fc26.x86_64                               3/15 
  Verifying   : fribidi-0.19.7-2.fc24.x86_64                              4/15 
  Verifying   : libass-0.13.4-1.fc25.x86_64                               5/15 
  Verifying   : schroedinger-1.0.11-10.fc24.x86_64                        6/15 
  Verifying   : libmfx-1.19-1.20170114gita5ba231.fc25.x86_64              7/15 
  Verifying   : libva-1.7.3-3.fc25.x86_64                                 8/15 
  Verifying   : ocl-icd-2.2.11-1.fc25.x86_64                              9/15 
  Verifying   : lame-libs-3.99.5-6.fc26.x86_64                           10/15 
  Verifying   : opencore-amr-0.1.3-4.fc24.x86_64                         11/15 
  Verifying   : vo-amrwbenc-0.1.3-1.fc24.x86_64                          12/15 
  Verifying   : x264-libs-0.148-15.20170121git97eaef2.fc26.x86_64        13/15 
  Verifying   : xvidcore-1.3.4-2.fc24.x86_64                             14/15 
  Verifying   : libavdevice-3.2.4-1.fc26.x86_64                          15/15 

Installed:
  ffmpeg.x86_64 3.2.4-1.fc26                                                   
  ffmpeg-libs.x86_64 3.2.4-1.fc26                                              
  fribidi.x86_64 0.19.7-2.fc24                                                 
  lame-libs.x86_64 3.99.5-6.fc26                                               
  libass.x86_64 0.13.4-1.fc25                                                  
  libavdevice.x86_64 3.2.4-1.fc26                                              
  libmfx.x86_64 1.19-1.20170114gita5ba231.fc25                                 
  libva.x86_64 1.7.3-3.fc25                                                    
  ocl-icd.x86_64 2.2.11-1.fc25                                                 
  opencore-amr.x86_64 0.1.3-4.fc24                                             
  schroedinger.x86_64 1.0.11-10.fc24                                           
  vo-amrwbenc.x86_64 0.1.3-1.fc24                                              
  x264-libs.x86_64 0.148-15.20170121git97eaef2.fc26                            
  x265-libs.x86_64 2.2-1.fc26                                                  
  xvidcore.x86_64 1.3.4-2.fc24                                                 

Complete!
[root@localhost]#

Just test te ffmpeg tools.