wsl -l
wsl --set-default Ubuntu
wsl --set-default-version 2wsl -l -v
wsl --set-version Ubuntu 2create /etc/wsl.conf
[automount]
options = "metadata"#set hostname
echo "Enter hostname:"
read host_name
hostnamectl set-hostname $host_name
#set ist timezone
rm -rf /etc/localtime | exit 0
ln -s /usr/share/zoneinfo/Asia/Kolkata /etc/localtime
#increase history size
echo 'export HISTSIZE=10000
export HISEFILESIZE=10000' >> /root/.bashrc
before_shutdown.sh
#!/bin/bash
#remove file older than 7 days
find /var/log -name "*.log" -type f -mtime +7
#test
touch "/opt/before_shutdown_tmp_file_$(date +%s)"echo '[Unit]
Description=before_shutdown
[Service]
ExecStart=/bin/true
Type=oneshot
RemainAfterExit=true
ExecStop=/opt/before_shutdown.sh
[Install]
WantedBy=multi-user.target' > /etc/systemd/system/before_shutdown.servicesystemctl daemon-reload
systemctl enable before_shutdown
systemctl start before_shutdownWhy Strace?
– Trace system call
– Troubleshooting issue with any binary command
– Debugging
strace ls
strace -c ls
strace -e trace=network nc -v -n 127.0.0.1 8080More:
https://www.geeksforgeeks.org/strace-command-in-linux-with-examples/
Note : This does not work because IO pins does not enough power to run fan.
fan.py
import RPi.GPIO as GPIO
from time import sleep
import sys
GPIO.setwarnings(False)
GPIO.setmode(GPIO.BOARD)
GPIO.setup(8, GPIO.OUT, initial=GPIO.LOW)
if sys.argv[1] == "on":
GPIO.output(8, GPIO.HIGH)
print("on")
else:
GPIO.output(8, GPIO.LOW)
print("off")Dockerfile
FROM python:slim-buster
WORKDIR /fan
RUN apt update && \
apt install python-rpi.gpio python3-rpi.gpio -y
COPY fan.py .Docker build
docker build -t fan .Docker run command switch on
docker run -it --device /dev/gpiomem fan python2 fan.py onDocker run command switch off
docker run -it --device /dev/gpiomem fan python2 fan.py offfan.sh
#!/bin/bash
cpu=$(</sys/class/thermal/thermal_zone0/temp)
cpu_temp=$(echo "$cpu/1000" | /usr/bin/bc)
echo $cpu_temp
if(("cpu_temp" >= "65"))
then
echo "more 65 on fan"
docker run -it --device /dev/gpiomem fan python2 fan.py on
else
echo "less 65 off fan"
docker run -it --device /dev/gpiomem fan python2 fan.py off
fi
More: https://raspberrypihq.com/making-a-led-blink-using-the-raspberry-pi-and-python/
https://stackoverflow.com/questions/48441737/docker-error-no-access-to-dev-mem-try-running-as-root
a='hello world
hello world
hello world
hello world
hello world ad a a t t hello'
n=0
> result.txt
for word in $a
do
wcount=$(echo $a| grep -o $word | wc -l)
echo "$word : $wcount" >> result.txt
done
cat result.txt | uniqyum install expect tcl tcllibdd if=/dev/sda | ssh USERNAME@IP_ADDR dd of=sda.isoxfs_undelete sda.isoMore :
https://github.com/ianka/xfs_undelete
https://unix.stackexchange.com/questions/132797/how-to-dd-a-remote-disk-using-ssh-on-local-machine-and-save-to-a-local-disk
Open port using NC:
nc 8888Listen port:
nc localhost 8888
Send packet using bash:
echo -n "hello" >/dev/tcp/localhost/8888#Dockerfile
FROM ubuntu
RUN apt update -y
RUN apt install cifs-utils -y
docker build -t cifs .docker run -it --cap-add SYS_ADMIN --cap-add DAC_READ_SEARCH -cap-add NET_BIND_SERVICE cifs bash#centos with privileged (working)
docker run --privileged -it --cap-add SYS_ADMIN --cap-add DAC_READ_SEARCH --cap-add NET_BIND_SERVICE centos bashmount -t cifs -o username=a,password=a //192.168.0.228/public /mntmount -t cifs -o username=a,password=a //192.168.0.228/public /mntmount -t cifs -o username=a,password=a,ro,domain=WORKGROUP //192.168.0.228/public /a -vWhy?
– Run process in background
– Run database backup in background
Tmux:
#List
tmux ls
#Start session
tmux new -s mysession
#Reconnect
tmux a -t session_name
#Disconnect
ctrl + b + D
#Reconnect to 0 session
tmux a -t 0
More : https://tmuxcheatsheet.com
Screen :
#List
screen -ls
#Named session
screen -A -m -d -S session_name command
#Reconnect to named session
screen -r session_name
#Disconnect
CTRL + a + dhttps://gist.github.com/jctosta/af918e1618682638aa82
Nohup:
Nohup command &It’s create nohup.out file in same directory with all command logs
Jobs:
jobs
fg
bg