Master Master replication tutorial for Mariadb

We have two servers. lets call them mater1 (1.1.1.1) and master2 (2.2.2.2) .
This instruction is tested for mariadb 10.1 on Debian 8.

First set my.cnf on both servers:

on master1:

[mysqld]
server-id=1
bind-address = 0.0.0.0
log_bin=/var/log/mysql/mariadb-bin
expire_logs_days=10
sync_binlog = 1
slave_compressed_protocol = 1
binlog_format = row

#to avoid in PRIMARY / UNIQUE key collisions when we write on both servers
auto-increment-increment=2
auto-increment-offset=1

on master2:

[mysqld]
server-id=2 #server id of each server should be unique
bind-address = 0.0.0.0
log_bin=/var/log/mysql/mariadb-bin
expire_logs_days=10
sync_binlog = 1
slave_compressed_protocol = 1
binlog_format = row


--------------
copy databases form master1 to master2

on master1
mysqldump -uroot -p --opt --routines --triggers --events --single-transaction --master-data=2 -A > alldb.sql

on maste2:
mysql -uroot -p < alldb.sql

--------------

Now setting up the databases


On master1:

MariaDB [(none)]> create user 'replication'@'2.2.2.2' identified by 'MYSECRETPASSWD';
MariaDB [(none)]> grant replication slave on *.* to 'replication'@'2.2.2.2';
MariaDB [(none)]> flush privileges;

On master2:
MariaDB [(none)]> create user 'replication'@'1.1.1.1' identified by 'MYSECRETPASSWD';
MariaDB [(none)]> grant replication slave on *.* to 'replication'@'1.1.1.1';
MariaDB [(none)]> flush privileges;


on Master 1:

MariaDB [(none)]> SELECT @@GLOBAL.gtid_current_pos;
+---------------------------+
| @@GLOBAL.gtid_current_pos |
+---------------------------+
| 0-1-26067388              |
+---------------------------+



on Master 2:
MariaDB [(none)]> flush privileges;
MariaDB [(none)]> stop slave;
MariaDB [(none)]> reset slave;
MariaDB [(none)]> set global gtid_slave_pos = "0-1-26067388";
MariaDB [(none)]> change master to master_host='1.1.1.1', master_user='replication', master_password='MYSECRETPASSWD', master_use_gtid=slave_pos;
MariaDB [(none)]> start slave; 

MariaDB [(none)]> SELECT @@GLOBAL.gtid_current_pos;
+---------------------------+
| @@GLOBAL.gtid_current_pos |
+---------------------------+
| 0-2-26067398              |
+---------------------------+


on Master 1:

MariaDB [(none)]> stop slave;
MariaDB [(none)]> reset slave;
MariaDB [(none)]> set global gtid_slave_pos = "0-2-26067398";
MariaDB [(none)]> change master to master_host='2.2.2.2', master_user='replication', master_password='MYSECRETPASSWD', master_use_gtid=slave_pos;
MariaDB [(none)]> start slave;

Check whether slaves are set properly:

MariaDB [(none)]> show slave status\G;

you should see both:

  Slave_IO_Running: Yes
  Slave_SQL_Running: Yes



---------
Test replication by creating a new database on master1:

MariaDB [(none)]> create database replication_test;

On Master2, check whether replication_test in created:

MariaDB [(none)]> show databases;
+--------------------+
| Database
|
+--------------------+
| information_schema |
| mysql
|
| performance_schema |
| replication_test
|
+--------------------+

To be absolutely sure, try the same tests the othe way round.

That's it. enjyo Master/Master replication.

Curtesy of the book MariaDB High Performance-Packt Publishing (2014) by Pierre Mavro

Increase session timeout of PhpMyAmin

Changing php.ini will change the session duration for all the websites running on the server. To change it just for PhpMyAdmin, open config.inc.php and add:

$sessionDuration = 60*60*24*7; // 60*60*24*7 = one week
ini_set('session.gc_maxlifetime', $sessionDuration);
$cfg['LoginCookieValidity'] = $sessionDuration;

source

How to fix 'perl: warning: Please check that your locale settings:' in Debian

Use:

export LANGUAGE=en_US.UTF-8
export LC_ALL=en_US.UTF-8
export LANG=en_US.UTF-8
export LC_TYPE=en_US.UTF-8

It works for Debian.

Source

Reset debian root password through KVM

Boot into grub, select single user but do not press enter.
Press e to bring you into edit mode.
Scroll down to the kernel line, it starts with “linux /boot/vmlinuz-2.6…….”
Scroll to the end of that line and press space key once and type

init=/bin/bash

Press Crtl x to boot

Then type

mount -rw -o remount /

Now you can right to disk and change password or whatever else you want

----------------------

referece:

https://derwynd.com/2011/04/14/debian-squeeze-change-root-password/

Deploy django on Debian with gunicorn using upstart

In my experience gunicorn is more stable and uses less memory than uwsgi to handle the same number of requests. It is also much simpler to configure and deploy.

The only issue with it is that finding good straightforward tutorial on its deployment hasn't been easy for me. The problem araise not by gunicorn but the rather convulted method of supervisor which adds more complexity to the process.

Fortunately there is the much simpler way to keep gunicorn running:‌ upstart

First you need to install pip and virtaulenv:

apt-get install python-pip

pip install virtualenv

Switch to a non-root user and create a virtualenv

su myuser 

virtualenv ~/.myenv

virtualenv ~/.myenv

activate the virtaualenv

source ~/.myenv/bin/activate

Install gunicorn while you'r on your virtualenv:

(.myenv)# pip install gunicorn

create a gunicorn.sh in  /path/to/project, like this:

#!/bin/bash

NAME="myproject"                                  # Name of the application

DJANGODIR=/path/to/project             # Django project directory

SOCKFILE=/tmp/gunicorn.sock  # we will communicte using this unix socket

USER=john                                        # the user to run as

GROUP=www-data                                     # the group to run

NUM_WORKERS=9                                     # twice the number of cpu cores

DJANGO_SETTINGS_MODULE=sai.settings             # which settings file should Django use

DJANGO_WSGI_MODULE=sai.wsgi                     # WSGI module name

echo "Starting $NAME as `whoami`"

# Activate the virtual environment

cd $DJANGODIR

source /home/user/.virtualenv/bin/activate

export DJANGO_SETTINGS_MODULE=$DJANGO_SETTINGS_MODULE

export PYTHONPATH=$DJANGODIR:$PYTHONPATH

# Create the run directory if it doesn't exist

RUNDIR=$(dirname $SOCKFILE)

test -d $RUNDIR || mkdir -p $RUNDIR

# Start your Django Unicorn

# Programs meant to be run under supervisor should not daemonize themselves (do not use --daemon)

exec /home/john/.virtualenv/bin/gunicorn ${DJANGO_WSGI_MODULE}:application \

  --name $NAME \

  --workers $NUM_WORKERS \

  --user=$USER --group=$GROUP \

  --bind=unix:$SOCKFILE \

  --log-level=debug \

  --log-file=-

Note: DO NOT create /tmp/gunicorn.sock  
gunicorn will do that for you


Make sure that upstart is installed:

apt-get install upstart

Now create an upstart job in /etc/init to run gunicorn.sh

nano /etc/init/gunicorn.conf

And put in it:

description "Gunicorn application server handling myproject"

start on runlevel [2345]

stop on runlevel [!2345]

respawn

setuid john

setgid www-data

chdir /path/to/project

exec bash gunicorn.sh

Now you can start gunicorn like any service :

service gunicorn restart

The only remaining step is to pass request to gunicorn in nginx, by a file like this:

upstream myproject {

    server unix:///tmp/gunicorn.sock;    # the socket will be created automatically

    }

server {

#...other stuff

location / {
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header Host $http_host;

        if (!-f $request_filename) {

            proxy_pass http://myproject;

            break;

        }

    }

}

Note 2: If you just started upstart, you may need to  reboot to be able to service gunicorn restart.

That's it!
Restart nginx and enjoy gunicorn.

Take screeshot gallery of a video

#apt-get install ffmpeg
#apt-get install imagemagick
#!/bin/bash
# This script will create a screenshot gallery of a given video very fast


filename=$1

videolable=$1

#ffmpeg  -i $filename -r 0.0033 -vf scale=-1:120 -vcodec png capture-2d.png

ffmpeg -ss 00:00:10 -i $filename -frames 1 -vf "select=not(mod(n\,1000)),scale=320:240,tile=2x3" ff.png


res=`ffmpeg -i $filename 2>&1 | grep -oP 'Stream .*, \K[0-9]+x[0-9]+'`

size=`du -h $filename | awk '{print $1}'`

duration=`ffmpeg -i $filename 2>&1 | grep Duration | cut -d ' ' -f 4 | sed s/,//`


#montage -border 10x10 -pointsize 14  -background black -fill white -gravity NorthWest  -title "\n$filename ( $res )\nSize:$size  Duration:$duration "  out.png screenshotgallery.png



width=`convert ff.png -ping -format "%w" info:`
height=120
fontsize=20


text="$videolable\nResolution($res)\nSize:($size)\nDuration:$duration\n"




convert -background white -fill black  \
           -size ${width}x${height} -pointsize 24 label:${text}  label.gif






convert -append ff.png   label.gif out.jpg

rm ff.png

echo "Done!"

How to install ffmpeg on Debian 8

is now available for Jessy as a backport: https://packages.debian.org/jessie-backports/ffmpeg

Add something like this to /etc/apt/sources.list (with your preferred mirror):

deb http://ftp.uk.debian.org/debian jessie-backports main

Then

apt-get update
apt-get install ffmpeg

Source: https://superuser.com/a/1082860

Install ffmpeg in debian 8 jessie

Installing ffmpeg from source have been a pain in the ass for me that wasted 5 hours of my time with no success.

On the other hand ffmpeg is not in debian jessie repo. But thankfully there is still a simple solution:

It is now available for Jessy as a backport: https://packages.debian.org/jessie-backports/ffmpeg

Add something like this to /etc/apt/sources.list (with your preferred mirror):

deb http://ftp.debian.org/debian jessie-backports main

Then

apt-get update
apt-get install ffmpeg







Which installs `ffmpeg version 3.2.2-1~bpo8+1`







Thanks this good fella, Dan

Install torrent seedbox on debian vps

Thanks tutorial by Mikhail Danial - http://youtu.be/ahIdUr3yW64 (with slight modifications)



apt-get update

apt-get install -y apache2 nano

adduser --disabled-password --system --home /var/lib/deluge --gecos "SamRo Deluge server" --group deluge

touch /var/log/deluged.log

touch /var/log/deluge-web.log

chown deluge:deluge /var/log/deluge*

apt-get update

apt-get install -y deluged

apt-get install -y deluge-webui

nano /etc/default/deluge-daemon
-----------------------------------------------------------------------
# Configuration for /etc/init.d/deluge-daemon
# The init.d script will only run if this variable non-empty.
DELUGED_USER="deluge"
# Should we run at startup?
RUN_AT_STARTUP="YES"
-----------------------------------------------------------------------


nano /etc/init.d/deluge-daemon
-----------------------------------------------------------------------
#!/bin/sh
### BEGIN INIT INFO
# Provides:          deluge-daemon
# Required-Start:    $local_fs $remote_fs
# Required-Stop:     $local_fs $remote_fs
# Should-Start:      $network
# Should-Stop:       $network
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Daemonized version of deluge and webui.
# Description:       Starts the deluge daemon with the user specified in
#                    /etc/default/deluge-daemon.
### END INIT INFO

# Author: Adolfo R. Brandes
# Updated by: Jean-Philippe "Orax" Roemer

PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
DESC="Deluge Daemon"
NAME1="deluged"
NAME2="deluge"
DAEMON1=/usr/bin/deluged
DAEMON1_ARGS="-d"             # Consult `man deluged` for more options
DAEMON2=/usr/bin/deluge-web
DAEMON2_ARGS=""               # Consult `man deluge-web` for more options
PIDFILE1=/var/run/$NAME1.pid
PIDFILE2=/var/run/$NAME2.pid
UMASK=022                     # Change this to 0 if running deluged as its own user
PKGNAME=deluge-daemon
SCRIPTNAME=/etc/init.d/$PKGNAME

# Exit if the package is not installed
[ -x "$DAEMON1" -a -x "$DAEMON2" ] || exit 0

# Read configuration variable file if it is present
[ -r /etc/default/$PKGNAME ] && . /etc/default/$PKGNAME

# Load the VERBOSE setting and other rcS variables
[ -f /etc/default/rcS ] && . /etc/default/rcS

# Define LSB log_* functions.
# Depend on lsb-base (>= 3.0-6) to ensure that this file is present.
. /lib/lsb/init-functions

if [ -z "$RUN_AT_STARTUP" -o "$RUN_AT_STARTUP" != "YES" ]
then
   log_warning_msg "Not starting $PKGNAME, edit /etc/default/$PKGNAME to start it."
   exit 0
fi

if [ -z "$DELUGED_USER" ]
then
    log_warning_msg "Not starting $PKGNAME, DELUGED_USER not set in /etc/default/$PKGNAME."
    exit 0
fi

#
# Function to verify if a pid is alive
#
is_alive()
{
   pid=`cat $1` > /dev/null 2>&1
   kill -0 $pid > /dev/null 2>&1
   return $?
}

#
# Function that starts the daemon/service
#
do_start()
{
   # Return
   #   0 if daemon has been started
   #   1 if daemon was already running
   #   2 if daemon could not be started

   is_alive $PIDFILE1
   RETVAL1="$?"

   if [ $RETVAL1 != 0 ]; then
       rm -f $PIDFILE1
       start-stop-daemon --start --background --quiet --pidfile $PIDFILE1 --make-pidfile \
       --exec $DAEMON1 --chuid $DELUGED_USER --user $DELUGED_USER --umask $UMASK -- $DAEMON1_ARGS
       RETVAL1="$?"
   else
       is_alive $PIDFILE2
       RETVAL2="$?"
       [ "$RETVAL2" = "0" -a "$RETVAL1" = "0" ] && return 1
   fi

   is_alive $PIDFILE2
   RETVAL2="$?"

   if [ $RETVAL2 != 0 ]; then
        sleep 2
        rm -f $PIDFILE2
        start-stop-daemon --start --background --quiet --pidfile $PIDFILE2 --make-pidfile \
        --exec $DAEMON2 --chuid $DELUGED_USER --user $DELUGED_USER --umask $UMASK -- $DAEMON2_ARGS
        RETVAL2="$?"
   fi
   [ "$RETVAL1" = "0" -a "$RETVAL2" = "0" ] || return 2
}

#
# Function that stops the daemon/service
#
do_stop()
{
   # Return
   #   0 if daemon has been stopped
   #   1 if daemon was already stopped
   #   2 if daemon could not be stopped
   #   other if a failure occurred

   start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --user $DELUGED_USER --pidfile $PIDFILE2
   RETVAL2="$?"
   start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --user $DELUGED_USER --pidfile $PIDFILE1
   RETVAL1="$?"
   [ "$RETVAL1" = "2" -o "$RETVAL2" = "2" ] && return 2

   rm -f $PIDFILE1 $PIDFILE2

   [ "$RETVAL1" = "0" -a "$RETVAL2" = "0" ] && return 0 || return 1
}

case "$1" in
  start)
   [ "$VERBOSE" != no ] && log_daemon_msg "Starting $DESC" "$NAME1"
   do_start
   case "$?" in
      0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
      2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
   esac
   ;;
  stop)
   [ "$VERBOSE" != no ] && log_daemon_msg "Stopping $DESC" "$NAME1"
   do_stop
   case "$?" in
      0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
      2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
   esac
   ;;
  restart|force-reload)
   log_daemon_msg "Restarting $DESC" "$NAME1"
   do_stop
   case "$?" in
     0|1)
      do_start
      case "$?" in
         0) log_end_msg 0 ;;
         1) log_end_msg 1 ;; # Old process is still running
         *) log_end_msg 1 ;; # Failed to start
      esac
      ;;
     *)
        # Failed to stop
      log_end_msg 1
      ;;
   esac
   ;;
  *)
   echo "Usage: $SCRIPTNAME {start|stop|restart|force-reload}" >&2
   exit 3
   ;;
esac

:
-----------------------------------------------------------------------


chmod a+x /etc/init.d/deluge-daemon

update-rc.d deluge-daemon defaults

reboot -h now

------------------------

After new login:

mkdir /var/www/torrent

In browser vitis:

yourserverip::8112

Enter the server password 'deluge' and reset it.

Go to `Preferences` and set `/var/www/torrent` as the download path.

Good to Go!




This tutorial works on Debian  7 and 8. But in Debian 8 apache2 configs need to be a bit tweaked to show the files in /torrent folder.

You need to add these lines :

Options +Indexes
IndexOptions FancyIndexing FoldersFirst NameWidth=* DescriptionWidth=*

to /etc/apache2/sites-available/000-default.conf

and change the DocumentRoot from /var/www/html to /var/www

In order to be able to have proper directory listing

Source:
https://youtu.be/ahIdUr3yW64

How to Secure Specific URL in Apache

This article will help you secure specific url in Apache. For example our site has an url likehttp://tecadmin.net/admin/” and we need that only the authorized users or ips can access/admin/ section.

Setup IP Based Restriction on Specific URL

Step 1: Edit apache configuration file and add below entry in websites virtual host.

<Location /admin>
Order deny,allow
Deny from all
Allow from 192.168.10.111
Allow from 111.222.333.444
</Location>

Step 2: Save Apache configuration file and restart apache service.

# service httpd restart

Step 3: Try to access your site from any other ip. Also check from given ip in configuration file.

Setup User Authentication on Specific URL

Step 1: Edit apache configuration file and add below entry in website virtual host.

<Location /admin>
AuthUserFile /var/www/htpasswd/.htpasswd
AuthName "Password Protected Area"
AuthType Basic
Require valid-user
</Location>

Step 2: Create htpasswd file using below command.

# htpasswd -cm /var/www/htpasswd/.htpasswd myuser

New password:
Re-type new password:
Adding password for user myuser

Step 3:
Restart apache and access your site url. It will prompt for login details.

# service httpd restart

Thanks for using this article, I hope this article fulfill your needs. Click here to read more details about apache location directive.

source