How-tos (Some useful Linux tips)

Convert all wav files to flac files in a folder

for i in *.wav; do ffmpeg -i "$i" "$i".flac ; done

for i in *.wav; do ffmpeg -i "$i" -acodec mp3 -ab 320k "$i".mp3 ; done

for i in *.flac; do ffmpeg -i "$i" -af aresample=dither_method=triangular -sample_fmt s16 -ar 44100 "$i".flac ; done

for f in *.flac; do flac -cd "$f" | lame -b 320 - "${f%.*}".mp3; done

Note: this will exclude videos already compressed (named with '_compressed.mp4')

find . \( -iname "*.mp4" -or -iname "*.mov" \) -and ! -name "*_compressed.*" -print0 | while read -d $'\0' file; do ffmpeg -i "$file" -nostdin -c:v libx264 -crf 28 -preset fast -y "${file%.*}_compressed.mp4"; done

sudo apt install libheif-examples
for file in *.heic; do heif-convert "$file" "${file/%.heic/.jpg}"; done

totem "$(ls -R | shuf -n1)"

gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/ebook \
    -dNOPAUSE -dQUIET -dBATCH -dDetectDuplicateImages \
    -dCompressFonts=true -r150 -sOutputFile=output.pdf input.pdf

Summary of -dPDFSETTINGS:

• dPDFSETTINGS=/screen lower quality, smaller size. (72 dpi)
• dPDFSETTINGS=/ebook for better quality, but slightly larger pdfs. (150 dpi)
• dPDFSETTINGS=/prepress output similar to Acrobat Distiller "Prepress Optimized" setting (300 dpi)
• dPDFSETTINGS=/printer selects output similar to the Acrobat Distiller "Print Optimized" setting (300 dpi)
• dPDFSETTINGS=/default selects output intended to be useful across a wide variety of uses, possibly at the expense of a larger output file

After upgrading to Ubuntu 22.04 I had some issue to read some video files (Totem crash at startup, display the error "The specified movie could not be found" or open the video with a strange format. I did install the Intel non-free drivers to solve this issue:

sudo apt install intel-media-va-driver-non-free ubuntu-restricted-extras

# remove lrc files
find -type f -name "*.lrc" -delete
# remove .DS_Store files
find -type f -name ".DS_Store" -delete

fdupes -rdN .

tar -zxvf file.tar.gz

tar -xvjf file.tar.bz2 

find . -type d -delete

find . -iname "*.mp3" -print

curl -4 -o /dev/null http://bouygues.testdebit.info/100M.iso

curl -o /tmp/temp.iso https://bouygues.testdebit.info/100M.iso
curl -4 -o /dev/null -F "filecontent=@/tmp/temp.iso" http://bouygues.testdebit.info

host myip.opendns.com resolver1.opendns.com

sudo netstat -antp

who

sudo slay user_name

sudo ufw status verbose

sudo iftop -i enp9s0

ssh user@host -XC application

ftpasswd --passwd --name=bob --uid=1001 --home=/home/bob --shell=/bin/false

ncftp -u username -p apssword ftp://ftpperso.free.fr/dir/

sudo ncftpput -R -u username ftpperso.free.fr / /dir_to_copy/*

sudo lshw | more

sudo dmidecode

sudo lscpu

upower -i /org/freedesktop/UPower/devices/battery_BAT0

wavemon

sudo glances --enable-plugin sensors

cpufreq-info

sudo journalctl --since "2023-01-01" | grep temperature

sudo powertop

sudo chkrootkit

sudo gt5

//check current kernel
uname -r
//check if list of old kernels is correct 
dpkg -l linux-{image,headers}-"[0-9]*" | awk '/^ii/{ print $2}' | grep -v -e `uname -r | cut -f1,2 -d"-"` | grep -e '[0-9]'
//purge old kernels
dpkg -l linux-{image,headers}-"[0-9]*" | awk '/^ii/{ print $2}' | grep -v -e `uname -r | cut -f1,2 -d"-"` | grep -e '[0-9]' | xargs sudo apt-get -y purge

sudo smartctl -A /dev/sda

sudo hdparm -y /dev/sdb

sudo hdparm -C /dev/sdb

sudo hdparm -B /dev/sdb

60 = 5x60 = (5 minutes)

sudo hdparm -B60 /dev/sdb

Install cifs/nfs

sudo apt install nfs-common
sudo apt install cifs-utils

brsaneconfig4 -a name=(name your device) model=(model name) ip=xx.xx.xx.xx

https://support.brother.com/g/b/downloadhowto.aspx?c=us_ot&lang=en&prod=dcp7055w_us_eu_as&os=128&dlid=dlf006645_000&flang=4&type3=566

Get SSH banned IP

fail2ban-client status sshd

• Live statistics

tail -f access.log | goaccess -

• Using single log file

goaccess access.log

• Using all log files (including .gz files)

zcat -f access.log* | goaccess -

• Date ranges

sed -n '/'$(date '+%d\/%b\/%Y' -d 'last week')'/,$ p' access.log | goaccess -a -
sed -n '/'$(date '+%d\/%b\/%Y' -d 'last month')'/,$ p' access.log | goaccess -a - 
sed -n '/'$(date '+%d\/%b\/%Y' -d '1 month ago')'/,$ p' access.log | goaccess -a - 
sed -n '/'$(date '+%d\/%b\/%Y' -d '1 week ago')'/,$ p' access.log | goaccess -a - 
sed -n '/'$(date '+%d\/%b\/%Y' -d 'yesterday')'/,$ p' access.log | goaccess -a - 
sed -n '/'$(date '+%d\/%b\/%Y' -d 'today')'/,$ p' access.log | goaccess -a -

goaccess access.log -o /var/www/html/report.html --log-format=COMBINED --real-time-html

awk '{print $9}' access.log | sort | uniq -c | sort -rn

cd /var/log/nginx/
awk '($9 ~ /404/)' access.log | awk '{print $7}' | sort | uniq -c | sort -rn

awk -F\" '($2 ~ /\.(jpg|gif)/ && $4 !~ /^https:\/\/eolienne\.f4jr\.org/){print $4}' access.log | sort | uniq -c | sort

awk '/Jan\/2024/ {print $1};' access.log | sort | uniq -c | sort -rn | head -20

awk 'BEGIN{ PROCINFO["sorted_in"]="@val_num_desc" }
     { a[$1]++; b[$1]+=$10 }
     END{ 
         for(i in a) { if(++c>10) break; printf "IP: %s: ",i ; system(sprintf("numfmt --to=iec-i %s",b[i])) ; } 
     }' access.log

sudo /usr/bin/mysql_secure_installation

sudo mysql -uroot -p
GRANT LOCK TABLES, SELECT, RELOAD ON *.* TO 'backup'@'localhost' IDENTIFIED BY 'PASSWORD';

/etc/mysql/conf.d/mysqldump.cnf

mysql -p -u root
 
CREATE DATABASE db_name;
 
GRANT ALL PRIVILEGES ON db_name.* TO 'db_user'@'localhost'
IDENTIFIED BY 'password' WITH GRANT OPTION;

mysql -p -u root -D db_name

SHOW TABLES ;

Installation of Airplay in Ubuntu 22.04 with Pulse Audio

• https://bugs.launchpad.net/ubuntu/+source/paprefs/+bug/1871899?comments=all

# Airplay ability 
sudo apt install pulseaudio build-essential paprefs git pulseaudio-module-raop intltool libjack0 pavucontrol pulseaudio-module-zeroconf
 
#bug pulseaudio 
sudo ln -s /usr/lib/pulse-16.1+dfsg1/ /usr/lib/pulse-16.1
pactl load-module module-raop-discover

Discover Airplay in Ubuntu 22.10 with PipeWire

sudo vi /etc/pipewire/pipewire.conf

Add the following line to load module inside the context.modules = [ section

{ name = libpipewire-module-raop-discover }

sudo apt install libdvdnav4 libdvdread4 gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly libdvd-pkg
sudo dpkg-reconfigure libdvd-pkg
sudo apt install ubuntu-restricted-extras

pihole -up

Move the Dock 'Show Applications' button at top

gsettings set org.gnome.shell.extensions.dash-to-dock show-apps-at-top true

Move the windows control button to the left

gsettings set  org.gnome.desktop.wm.preferences button-layout 'close,minimize,maximize:'

Remove an IP address in case your IP address has been blocked by DSM firewall (Error message "IP Address blocked due to too many failed login attempts")

Login to your NAS using SSH with an admin group account

ssh user@192.168.x.x -p port_number

Once connected, get the root rights entering your password

sudo -i

Now remove the blocker IP address from the database

cd /etc
sqlite3 synoautoblock.db
sqlite> delete from AutoBlockIP where IP ="x.x.x.x";

• Raspberry Pi : https://www.raspberrypi.org/ - Tiny computer
• Pi-Hole : https://pi-hole.net - Ad blocking using DNS - With DNSCrypt-Proxy
• Firefox : https://www.mozilla.org/en-US/firefox/new/ - The Web Browser
• Bitwarden : https://bitwarden.com/open-source/ - Password manager
• MoodeAudio : http://www.moodeaudio.org/ - Audiophile-quality music playback
• HifiBerry : https://www.hifiberry.com/ - Audio additional boards for Rpi
• OpenHAB : https://www.openhab.org/ - Smart Home
• Home Assistant : https://www.home-assistant.io/ - Open source home automation
• DD-WRT : https://dd-wrt.com/ - Free your router
• Ubuntu : https://ubuntu.com/ - Linux distribution
• Shelly : https://www.shelly.com/en-fr - Smart Home Automation
• Nicotine+ : https://nicotine-plus.org/ - Soulseek is not dead
• Kodi : https://kodi.tv/ - Media Centre
• NGINX : https://www.nginx.com/ - Web Server
• Amplify : https://amplify.nginx.com - Web Server Monitoring
• VideoLAN : https://www.videolan.org/ - Powerful media player
• Waze : https://www.waze.com/ - GPS