How to prperly launch mjpg_streamer when a webcam is pluged in? - linux

I am trying to launch mjpg streamer when a webcam is plugged in.
So far I've been able to detect when the webcam is pluged and I've been able to launch it.
But two issues appear:
first the port doesn't appear to be open
second the process is killed after about 3 minutes
Im running on Ubuntu 18.04.4 LTS
here is what I assume is the culprit file
/etc/udev/rules.d/10-usbmount.rules
#https://stackoverflow.com/questions/20084740/udev-run-program-on-usb-flash-drive-insert
KERNEL=="video[0-9]*", ENV{ID_SERIAL}!="?*", SUBSYSTEMS=="usb", RUN+="/usr/bin/usbdevinserted"
/usr/bin/usbdevinserted
#!/bin/bash
echo $DEVNAME 2>&1 > /tmp/usbdevinfo
#set 2>&1 >> /tmp/usbdevinfo
if [[ $(pgrep mjpg_streamer) ]];
then
echo "Stoping Mjpg_Streamer" 2>&1 >> /tmp/usbdevinfo;
pkill mjpg_streamer;
echo "mjpg_Streamer stoped" 2>&1 >> /tmp/usbdevinfo;
fi
if [[ $(v4l2-ctl --device=$DEVNAME --all | grep "Video input") ]];
then
echo "launching mjpg_streamer on $DEVNAME" 2>&1 >> /tmp/usbdevinfo;
(mjpg_streamer -i "input_uvc.so -f 15 -r 1080x720 -d $DEVNAME" -o "output_http.so -w /pathToHome/mjpg-streamer/www -p 8080" 2>&1 >> /tmp/usbdevinfo) | at now
fi

Related

systemd service works different then running the .sh file from user shell trying run a VNC startup script with noVNC

I want to run a .sh file with a systemd service. Let's explain it a little bit. If I go to cd /home/ubuntu I can run ./vnc_startup.sh. This file creates a VNC connection and starts noVNC. Then I go to the browser open the address and login. I can run every command like as example rosrun rviz rviz because I have installed ROS.
If I use this service, it will not work:
cat /etc/systemd/system/novnc.service
[Unit]
After=NetworkManager.service time-sync.target
[Service]
Type=forking
User=ubuntu
Group=ubuntu
WorkingDirectory=/home/ubuntu
TimeoutStartSec=infinity
TimeoutStopSec=infinity
ExecStartPre=/bin/rm -f /home/ubuntu/no_vnc_startup.log
ExecStartPre=/bin/rm -f /home/ubuntu/vnc_startup.log
ExecStartPre=/bin/rm -f /home/ubuntu/wm.log
ExecStartPre=/bin/rm -f /home/ubuntu/wm_startup.log
ExecStart=/bin/bash -c "source /etc/environment; /home/ubuntu/vnc_startup.sh"
ExecStopPost=/bin/rm -f /home/ubuntu/no_vnc_startup.log
ExecStopPost=/bin/rm -f /home/ubuntu/vnc_startup.log
ExecStopPost=/bin/rm -f /home/ubuntu/wm.log
ExecStopPost=/bin/rm -f /home/ubuntu/wm_startup.log
[Install]
WantedBy=multi-user.target
I also tried it with systemctl --user start novnc.service and put the file inside /usr/lib/systemd/user instead of sudo systemctl start novnc.service and /etc/systemd/system/novnc.service.
Following workaround will work in the noVNC environment: I can open a Terminal. I can see ubuntu#hostname:~$. So it seems to be the right user and I am in the right working directory. Before running as example rosrun rviz rviz I have to run sudo su ubuntu. And then it works. If I had run ./vnc_startup.sh instead of running this script with systemd it works directly without the workaround with sudo su ubuntu.
Hard to explain. I hope you can understand me.
systemctl --user show-environment
HOME=/home/ubuntu
LANG=de_DE
LOGNAME=ubuntu
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin
SHELL=/bin/bash
USER=ubuntu
XDG_RUNTIME_DIR=/run/user/1001
The command printenv makes clear that maybe the DISPLAY=:0 is missing, so I tried it with adding
export DISPLAY=:0
xset q
And I also added Environment=XAUTHORITY=/home/ubuntu/.Xauthority:
[Unit]
After=NetworkManager.service time-sync.target
[Service]
Type=forking
User=ubuntu
Group=ubuntu
WorkingDirectory=/home/ubuntu
Environment=XAUTHORITY=/home/ubuntu/.Xauthority
TimeoutStartSec=infinity
TimeoutStopSec=infinity
ExecStartPre=/bin/rm -f /home/ubuntu/no_vnc_startup.log
ExecStartPre=/bin/rm -f /home/ubuntu/vnc_startup.log
ExecStartPre=/bin/rm -f /home/ubuntu/wm.log
ExecStartPre=/bin/rm -f /home/ubuntu/wm_startup.log
ExecStart=/bin/bash -c "source /etc/environment; export DISPLAY=:0; xset q; /home/ubuntu/vnc_startup.sh"
ExecStopPost=/bin/rm -f /home/ubuntu/no_vnc_startup.log
ExecStopPost=/bin/rm -f /home/ubuntu/vnc_startup.log
ExecStopPost=/bin/rm -f /home/ubuntu/wm.log
ExecStopPost=/bin/rm -f /home/ubuntu/wm_startup.log
[Install]
WantedBy=multi-user.target
Here my log files:
cat no_vnc_startup.log
New 'shlServer01:1 (ubuntu)' desktop is shlServer01:1
Starting applications specified in /home/ubuntu/.vnc/xstartup
Log file is /home/ubuntu/.vnc/shlServer01:1.log
r settings:
- Listen on :6901
- Flash security policy server
- Web server. Web root: /home/ubuntu/noVNC
- No SSL/TLS support (no cert file)
- proxying from :6901 to localhost:5901
Navigate to this URL:
http://shlServer01:6901/vnc.html?host=shlServer01&port=6901
Press Ctrl-C to exit
192.168.0.6 - - [15/Dec/2021 15:16:56] 192.168.0.6: Plain non-SSL (ws://) WebSocket connection
192.168.0.6 - - [15/Dec/2021 15:16:56] 192.168.0.6: Version hybi-13, base64: 'False'
192.168.0.6 - - [15/Dec/2021 15:16:56] 192.168.0.6: Path: '/websockify'
192.168.0.6 - - [15/Dec/2021 15:16:56] connecting to: localhost:5901
cat vnc_startup.log
Killing Xvnc process ID 63164
Xvnc process ID 63164 already killed
cat wm.log
/usr/bin/startxfce4: X server already running on display :0
xfce4-session: Cannot open display: .
▒xfce4-session --help▒ eingeben, um mehr ▒ber die Verwendung zu erfahren.
cat wm_startup.log
------------------ startup of Xfce4 window manager ------------------
No protocol specified
xset: unable to open display ":0"
No protocol specified
xset: unable to open display ":0"
No protocol specified
xset: unable to open display ":0"
No protocol specified
xrdb: Resource temporarily unavailable
xrdb: Can't open display ':0'
No protocol specified
No protocol specified
/usr/bin/startxfce4: X server already running on display :0
xfce4-session: Cannot open display: .
▒xfce4-session --help▒ eingeben, um mehr ▒ber die Verwendung zu erfahren.
What surprises me is that this is not the error. The error messages also come when I start the script from the terminal and then it works.
The vnc_startup.sh looks like following:
#!/bin/bash
### every exit != 0 fails the script
set -e
## print out help
help (){
echo "
OPTIONS:
-w, --wait (default) keeps the UI and the vncserver up until SIGINT or SIGTERM will received
-s, --skip skip the vnc startup and just execute the assigned command.
example: docker run consol/centos-xfce-vnc --skip bash
-d, --debug enables more detailed startup output
e.g. 'docker run consol/centos-xfce-vnc --debug bash'
-h, --help print out this help
Fore more information see: https://github.com/ConSol/docker-headless-vnc-container
"
}
if [[ $1 =~ -h|--help ]]; then
help
exit 0
fi
# should also source /home/ubuntu/generate_container_user
source /home/ubuntu/.bashrc
# add `--skip` to startup args, to skip the VNC startup procedure
if [[ $1 =~ -s|--skip ]]; then
echo -e "\n\n------------------ SKIP VNC STARTUP -----------------"
echo -e "\n\n------------------ EXECUTE COMMAND ------------------"
echo "Executing command: '${#:2}'"
exec "${#:2}"
fi
if [[ $1 =~ -d|--debug ]]; then
echo -e "\n\n------------------ DEBUG VNC STARTUP -----------------"
export DEBUG=true
fi
## correct forwarding of shutdown signal
cleanup () {
kill -s SIGTERM $!
exit 0
}
trap cleanup SIGINT SIGTERM
## write correct window size to chrome properties
/home/ubuntu/chrome-init.sh
## resolve_vnc_connection
VNC_IP=$(hostname -i)
## change vnc password
echo -e "\n------------------ change VNC password ------------------"
# first entry is control, second is view (if only one is valid for both)
mkdir -p "/home/ubuntu/.vnc"
PASSWD_PATH="/home/ubuntu/.vnc/passwd"
if [[ -f $PASSWD_PATH ]]; then
echo -e "\n--------- purging existing VNC password settings ---------"
rm -f $PASSWD_PATH
fi
if [[ $VNC_VIEW_ONLY == "true" ]]; then
echo "start VNC server in VIEW ONLY mode!"
#create random pw to prevent access
echo $(head /dev/urandom | tr -dc A-Za-z0-9 | head -c 20) | vncpasswd -f > $PASSWD_PATH
fi
echo "ubuntu" | vncpasswd -f >> $PASSWD_PATH
chmod 600 $PASSWD_PATH
## start vncserver and noVNC webclient
echo -e "\n------------------ start noVNC ----------------------------"
if [[ $DEBUG == true ]]; then echo "/home/ubuntu/noVNC/utils/launch.sh --vnc localhost:5901 --listen 6901"; fi
/home/ubuntu/noVNC/utils/launch.sh --vnc localhost:5901 --listen 6901 &> /home/ubuntu/no_vnc_startup.log &
PID_SUB=$!
echo -e "\n------------------ start VNC server ------------------------"
echo "remove old vnc locks to be a reattachable container"
vncserver -kill :1 &> /home/ubuntu/vnc_startup.log \
|| rm -rfv /tmp/.X*-lock /tmp/.X11-unix &> /home/ubuntu/vnc_startup.log \
|| echo "no locks present"
echo -e "start vncserver with param: VNC_COL_DEPTH=24, VNC_RESOLUTION=1280x1024\n..."
if [[ $DEBUG == true ]]; then echo "vncserver :1 -depth 24 -geometry 1280x1024"; fi
vncserver :1 -depth 24 -geometry 1280x1024 &> /home/ubuntu/no_vnc_startup.log
echo -e "start window manager\n..."
/home/ubuntu/wm_startup.sh &> /home/ubuntu/wm_startup.log
## log connect options
echo -e "\n\n------------------ VNC environment started ------------------"
echo -e "\nVNCSERVER started on DISPLAY= :1 \n\t=> connect via VNC viewer with $VNC_IP:5901"
echo -e "\nnoVNC HTML client started:\n\t=> connect via http://$VNC_IP:6901/?password=...\n"
if [[ $DEBUG == true ]] || [[ $1 =~ -t|--tail-log ]]; then
echo -e "\n------------------ /home/ubuntu/.vnc/*:1.log ------------------"
# if option `-t` or `--tail-log` block the execution and tail the VNC log
tail -f /home/ubuntu/*.log /home/ubuntu/.vnc/*:1.log
fi
if [ -z "$1" ] || [[ $1 =~ -w|--wait ]]; then
wait $PID_SUB
else
# unknown option ==> call command
echo -e "\n\n------------------ EXECUTE COMMAND ------------------"
echo "Executing command: '$#'"
exec "$#"
fi
The wm_startup.sh looks like this:
#!/usr/bin/env bash
### every exit != 0 fails the script
set -e
echo -e "\n------------------ startup of Xfce4 window manager ------------------"
### disable screensaver and power management
xset -dpms &
xset s noblank &
xset s off &
/usr/bin/startxfce4 --replace > /home/ubuntu/wm.log &
sleep 1
cat /home/ubuntu/wm.log
And it should not be important but the launch.sh file fom noVNC looks like this:
#!/usr/bin/env bash
# Copyright 2016 Joel Martin
# Copyright 2016 Solly Ross
# Licensed under MPL 2.0 or any later version (see LICENSE.txt)
usage() {
if [ "$*" ]; then
echo "$*"
echo
fi
echo "Usage: ${NAME} [--listen PORT] [--vnc VNC_HOST:PORT] [--cert CERT] [--ssl-only]"
echo
echo "Starts the WebSockets proxy and a mini-webserver and "
echo "provides a cut-and-paste URL to go to."
echo
echo " --listen PORT Port for proxy/webserver to listen on"
echo " Default: 6080"
echo " --vnc VNC_HOST:PORT VNC server host:port proxy target"
echo " Default: localhost:5900"
echo " --cert CERT Path to combined cert/key file"
echo " Default: self.pem"
echo " --web WEB Path to web files (e.g. vnc.html)"
echo " Default: ./"
echo " --ssl-only Disable non-https connections."
echo " "
exit 2
}
NAME="$(basename $0)"
REAL_NAME="$(readlink -f $0)"
HERE="$(cd "$(dirname "$REAL_NAME")" && pwd)"
PORT="6080"
VNC_DEST="localhost:5900"
CERT=""
WEB=""
proxy_pid=""
SSLONLY=""
die() {
echo "$*"
exit 1
}
cleanup() {
trap - TERM QUIT INT EXIT
trap "true" CHLD # Ignore cleanup messages
echo
if [ -n "${proxy_pid}" ]; then
echo "Terminating WebSockets proxy (${proxy_pid})"
kill ${proxy_pid}
fi
}
# Process Arguments
# Arguments that only apply to chrooter itself
while [ "$*" ]; do
param=$1; shift; OPTARG=$1
case $param in
--listen) PORT="${OPTARG}"; shift ;;
--vnc) VNC_DEST="${OPTARG}"; shift ;;
--cert) CERT="${OPTARG}"; shift ;;
--web) WEB="${OPTARG}"; shift ;;
--ssl-only) SSLONLY="--ssl-only" ;;
-h|--help) usage ;;
-*) usage "Unknown chrooter option: ${param}" ;;
*) break ;;
esac
done
# Sanity checks
which netstat >/dev/null 2>&1 \
|| die "Must have netstat installed"
netstat -ltn | grep -qs ":${PORT} .*LISTEN" \
&& die "Port ${PORT} in use. Try --listen PORT"
trap "cleanup" TERM QUIT INT EXIT
# Find vnc.html
if [ -n "${WEB}" ]; then
if [ ! -e "${WEB}/vnc.html" ]; then
die "Could not find ${WEB}/vnc.html"
fi
elif [ -e "$(pwd)/vnc.html" ]; then
WEB=$(pwd)
elif [ -e "${HERE}/../vnc.html" ]; then
WEB=${HERE}/../
elif [ -e "${HERE}/vnc.html" ]; then
WEB=${HERE}
elif [ -e "${HERE}/../share/novnc/vnc.html" ]; then
WEB=${HERE}/../share/novnc/
else
die "Could not find vnc.html"
fi
# Find self.pem
if [ -n "${CERT}" ]; then
if [ ! -e "${CERT}" ]; then
die "Could not find ${CERT}"
fi
elif [ -e "$(pwd)/self.pem" ]; then
CERT="$(pwd)/self.pem"
elif [ -e "${HERE}/../self.pem" ]; then
CERT="${HERE}/../self.pem"
elif [ -e "${HERE}/self.pem" ]; then
CERT="${HERE}/self.pem"
else
echo "Warning: could not find self.pem"
fi
# try to find websockify (prefer local, try global, then download local)
if [[ -e ${HERE}/websockify ]]; then
WEBSOCKIFY=${HERE}/websockify/run
if [[ ! -x $WEBSOCKIFY ]]; then
echo "The path ${HERE}/websockify exists, but $WEBSOCKIFY either does not exist or is not executable."
echo "If you intended to use an installed websockify package, please remove ${HERE}/websockify."
exit 1
fi
echo "Using local websockify at $WEBSOCKIFY"
else
WEBSOCKIFY=$(which websockify 2>/dev/null)
if [[ $? -ne 0 ]]; then
echo "No installed websockify, attempting to clone websockify..."
WEBSOCKIFY=${HERE}/websockify/run
git clone https://github.com/novnc/websockify ${HERE}/websockify
if [[ ! -e $WEBSOCKIFY ]]; then
echo "Unable to locate ${HERE}/websockify/run after downloading"
exit 1
fi
echo "Using local websockify at $WEBSOCKIFY"
else
echo "Using installed websockify at $WEBSOCKIFY"
fi
fi
echo "Starting webserver and WebSockets proxy on port ${PORT}"
#${HERE}/websockify --web ${WEB} ${CERT:+--cert ${CERT}} ${PORT} ${VNC_DEST} &
${WEBSOCKIFY} ${SSLONLY} --web ${WEB} ${CERT:+--cert ${CERT}} ${PORT} ${VNC_DEST} &
proxy_pid="$!"
sleep 1
if ! ps -p ${proxy_pid} >/dev/null; then
proxy_pid=
echo "Failed to start WebSockets proxy"
exit 1
fi
echo -e "\n\nNavigate to this URL:\n"
if [ "x$SSLONLY" == "x" ]; then
echo -e " http://$(hostname):${PORT}/vnc.html?host=$(hostname)&port=${PORT}\n"
else
echo -e " https://$(hostname):${PORT}/vnc.html?host=$(hostname)&port=${PORT}\n"
fi
echo -e "Press Ctrl-C to exit\n\n"
wait ${proxy_pid}
Suggesting to simply your /etc/systemd/system/novnc.service service unit with a single script for ExecStart command and a single script for ExecStop
/etc/systemd/system/novnc.service
[Unit]
After=NetworkManager.service time-sync.target
[Service]
Type=forking
User=ubuntu
Group=ubuntu
WorkingDirectory=/home/ubuntu
Environment=XAUTHORITY=/home/ubuntu/.Xauthority
TimeoutStartSec=infinity
TimeoutStopSec=infinity
ExecStart=/bin/bash -c "/home/ubuntu/servic_vnc_startup.sh"
ExecStop=/bin/bash -c "/home/ubuntu/servic_vnc_shutdown.sh"
[Install]
WantedBy=multi-user.target
/home/ubuntu/servic_vnc_startup.sh
#!\bin\bash
source /home/ubuntu/.bash_profile
source /etc/environment
export DISPLAY=:0
xset q;
rm -f /home/ubuntu/{no_vnc_startup.log,vnc_startup.log,wm.log,wm_startup.log}
/home/ubuntu/vnc_startup.sh
/home/ubuntu/servic_vnc_shutdown.sh
#!\bin\bash
source /home/ubuntu/.bash_profile
source /etc/environment
export DISPLAY=:0
xset q;
pkill -9 -f "/home/ubuntu/vnc_startup.sh"
rm -f /home/ubuntu/{no_vnc_startup.log,vnc_startup.log,wm.log,wm_startup.log}
Debugging
Login as user ubuntu.
Run /home/ubuntu/servic_vnc_startup.sh from command line.
If fails, fix it till it is successful.
Then try running /home/ubuntu/servic_vnc_startup.sh as user noboby:
sudo -u nobody "/home/ubuntu/servic_vnc_startup.sh"
User nobody has no shell and no environment context, as is the systemd service /etc/systemd/system/novnc.service.
If user nobody can run /home/ubuntu/servic_vnc_startup.sh then the /etc/systemd/system/novnc.service service unit can do as well.
Do same testing pattern with /home/ubuntu/servic_vnc_shutdown.sh
Lessons to learn:
Simplify service unit as much as possible.
Pull all scripting to a single shell script. Debug single shell script.
Avoid debugging handling service unit once deployed. Instead debug and modify called script.
Use user nobody user, to debug script to run without environment context and without shell.

Working around sudo in shell script child process

So the reason I am asking this is because I'm running two programs simultaneously that are persistent, on the child process a programm is running that requires sudo rights.
#!/bin/bash
echo "Name the file:"
read filename
while [[ 1 -lt 2 ]]
do
if [ -f /home/max/dump/$filename.eth ]; then
echo "File already exist."
read filename
else
break
fi
done
#Now calling a new terminal for dumping
gnome-terminal --title="tcpdump" -e "sh /home/max/dump/dump.sh $filename.eth"
ping -c 1 0 > /dev/null **Waiting for tcpdump to create file**
#Packet analysis program is being executed
Script dump.sh
#!/bin/bash
filename=$1
echo password | sudo tcpdump -i 2 -s 60000 -w /home/max/dump/$filename -U
host 192.168.3.2
#Sudo still asks me for my password though password is piped into stdin

Linux Script to check if process is running and act on the result

I have a process that fails regularly & sometimes starts duplicate instances..
When I run:
ps x |grep -v grep |grep -c "processname"
I will get:
2
This is normal as the process runs with a recovery process..
If I get
0
I will want to start the process
if I get:
4
I will want to stop & restart the process
What I need is a way of taking the result of ps x |grep -v grep |grep -c "processname"
Then setup a simple 3 option function
ps x |grep -v grep |grep -c "processname"
if answer = 0 (start process & write NOK & Time to log /var/processlog/check)
if answer = 2 (Do nothing & write OK & time to log /var/processlog/check)
if answer = 4 (stot & restart the process & write NOK & Time to log /var/processlog/check)
The process is stopped with
killall -9 process
The process is started with
process -b -c /usr/local/etc
My main problem is finding a way to act on the result of ps x |grep -v grep |grep -c "processname".
Ideally, I would like to make the result of that grep a variable within the script with something like this:
process=$(ps x |grep -v grep |grep -c "processname")
If possible.
Programs to monitor if a process on a system is running.
Script is stored in crontab and runs once every minute.
This works with if process is not running or process is running multiple times:
#! /bin/bash
case "$(pidof amadeus.x86 | wc -w)" in
0) echo "Restarting Amadeus: $(date)" >> /var/log/amadeus.txt
/etc/amadeus/amadeus.x86 &
;;
1) # all ok
;;
*) echo "Removed double Amadeus: $(date)" >> /var/log/amadeus.txt
kill $(pidof amadeus.x86 | awk '{print $1}')
;;
esac
0 If process is not found, restart it.
1 If process is found, all ok.
* If process running 2 or more, kill the last.
A simpler version. This just test if process is running, and if not restart it.
It just tests the exit flag $? from the pidof program. It will be 0 of process is running and 1 if not.
#!/bin/bash
pidof amadeus.x86 >/dev/null
if [[ $? -ne 0 ]] ; then
echo "Restarting Amadeus: $(date)" >> /var/log/amadeus.txt
/etc/amadeus/amadeus.x86 &
fi
And at last, a one liner
pidof amadeus.x86 >/dev/null ; [[ $? -ne 0 ]] && echo "Restarting Amadeus: $(date)" >> /var/log/amadeus.txt && /etc/amadeus/amadeus.x86 &
This can then be used in crontab to run every minute like this:
* * * * * pidof amadeus.x86 >/dev/null ; [[ $? -ne 0 ]] && echo "Restarting Amadeus: $(date)" >> /var/log/amadeus.txt && /etc/amadeus/amadeus.x86 &
cccam oscam
I adopted the #Jotne solution and works perfectly! For example for mongodb server in my NAS
#! /bin/bash
case "$(pidof mongod | wc -w)" in
0) echo "Restarting mongod:"
mongod --config mongodb.conf
;;
1) echo "mongod already running"
;;
esac
I have adopted your script for my situation Jotne.
#! /bin/bash
logfile="/var/oscamlog/oscam1check.log"
case "$(pidof oscam1 | wc -w)" in
0) echo "oscam1 not running, restarting oscam1: $(date)" >> $logfile
/usr/local/bin/oscam1 -b -c /usr/local/etc/oscam1 -t /usr/local/tmp.oscam1 &
;;
2) echo "oscam1 running, all OK: $(date)" >> $logfile
;;
*) echo "multiple instances of oscam1 running. Stopping & restarting oscam1: $(date)" >> $logfile
kill $(pidof oscam1 | awk '{print $1}')
;;
esac
While I was testing, I ran into a problem..
I started 3 extra process's of oscam1 with this line:
/usr/local/bin/oscam1 -b -c /usr/local/etc/oscam1 -t /usr/local/tmp.oscam1
which left me with 8 process for oscam1. the problem is this..
When I run the script, It only kills 2 process's at a time, so I would have to run it 3 times to get it down to 2 process..
Other than killall -9 oscam1 followed by /usr/local/bin/oscam1 -b -c /usr/local/etc/oscam1 -t /usr/local/tmp.oscam1, in *)is there any better way to killall apart from the original process? So there would be zero downtime?
If you changed awk '{print $1}' to '{ $1=""; print $0}' you will get all processes except for the first as a result. It will start with the field separator (a space generally) but I don't recall killall caring. So:
#! /bin/bash
logfile="/var/oscamlog/oscam1check.log"
case "$(pidof oscam1 | wc -w)" in
0) echo "oscam1 not running, restarting oscam1: $(date)" >> $logfile
/usr/local/bin/oscam1 -b -c /usr/local/etc/oscam1 -t /usr/local/tmp.oscam1 &
;;
2) echo "oscam1 running, all OK: $(date)" >> $logfile
;;
*) echo "multiple instances of oscam1 running. Stopping & restarting oscam1: $(date)" >> $logfile
kill $(pidof oscam1 | awk '{ $1=""; print $0}')
;;
esac
It is worth noting that the pidof route seems to work fine for commands that have no spaces, but you would probably want to go back to a ps-based string if you were looking for, say, a python script named myscript that showed up under ps like
root 22415 54.0 0.4 89116 79076 pts/1 S 16:40 0:00 /usr/bin/python /usr/bin/myscript
Just an FYI
The 'pidof' command will not display pids of shell/perl/python scripts. So to find the process id’s of my Perl script I had to use the -x option i.e. 'pidof -x perlscriptname'
I cannot get case to work at all.
Heres what I have:
#! /bin/bash
logfile="/home/name/public_html/cgi-bin/check.log"
case "$(pidof -x script.pl | wc -w)" in
0) echo "script not running, Restarting script: $(date)" >> $logfile
# ./restart-script.sh
;;
1) echo "script Running: $(date)" >> $logfile
;;
*) echo "Removed duplicate instances of script: $(date)" >> $logfile
# kill $(pidof -x ./script.pl | awk '{ $1=""; print $0}')
;;
esac
rem the case action commands for now just to test the script. the above pidof -x command is returning '1', the case statement is returning the results for '0'.
Anyone have any idea where I'm going wrong?
Solved it by adding the following to my BIN/BASH Script:
PATH=$PATH:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
In case you're looking for a more modern way to check to see if a service is running (this will not work for just any old process), then systemctl might be what you're looking for.
Here's the basic command:
systemctl show --property=ActiveState your_service_here
Which will yield very simple output (one of the following two lines will appear depending on whether the service is running or not running):
ActiveState=active
ActiveState=inactive
And if you'd like to know all of the properties you can get:
systemctl show --all your_service_here
If you prefer that alphabetized:
systemctl show --all your_service_here | sort
And the full code to act on it:
service=$1
result=`systemctl show --property=ActiveState $service`
if [[ "$result" == 'ActiveState=active' ]]; then
echo "$service is running" # Do something here
else
echo "$service is not running" # Do something else here
fi
If you are using CentOS, no need to write a script and set cron job. Here is one of the smartest ways to ensure systemd services restart on failure.
Make following changes to /usr/lib/systemd/system/mariadb.service
Then under the [Service] section in the file, add the following 2 lines:
Restart=always
RestartSec=3
After saving the file we need to reload the daemon configurations to ensure systemd is aware of the new file
systemctl daemon-reload
Read the following link for the complete steps -
https://jonarcher.info/2015/08/ensure-systemd-services-restart-on-failure/

Bash script to check if process is running and read user input to start if necessary

Having a problem with using nohup in a script. The script works properly if nohup is not used
to start the process. The following error is received when run:
./iper.sh: line 16: syntax error near unexpected token `;'
./iper.sh: line 16: ` [Yy]*) nohup iperf -s > /dev/null 2>&1&; break;;'
Here is the full script:
#!/bin/bash
echo "Checking to see if Iperf is running:"
sleep 2
ps cax | grep iperf > /dev/null
if [ $? -eq 0 ]; then
echo "Iperf is running."
else
echo "Iperf is not running."
fi
sleep 2
while true; do
read -p "Press Y to start Iperf or N to exit: " yn
case $yn in
[Yy]*) nohup iperf -s > /dev/null 2>&1&; break;;
[Nn]*) exit;;
esac
done
What is happening?
If you're going to terminate your command with & to put it to background, do not terminate it with another semicolon ; as well:
[Yy]*) nohup iperf -s > /dev/null 2>&1& break;;
Previously
2>&1&;
I guess you have an extra & in 2>&1&
Change it to 2>&1
Check with below script
#!/bin/bash
echo "Checking to see if Iperf is running:"
sleep 1
if `pgrep iperf >/dev/null 2>&1`
then
echo "iperf Running"
else
echo "iperf not Running"
fi
sleep 1
while true; do
echo "Do you wanna start Iperf (y/n)"
read -n 1 ch; p=`echo ${ch} | tr A-Z a-z`
case $p in
y)nohup iperf -s > /dev/null 2>&1 break;;
n)exit;;
*)continue;
esac
done
when this been executed it waits for user to press*ctrl + c* to come out
if you are using 2>&1&(for continuing without user interference)allowing user to do other work
replace below line in y) condition
nohup iperf -s > /dev/null 2>&1& break;;

Consuming bandwidth

I know how to write a basic bash script which uses wget to download a file, but how do I run this in an endless loop to download the specified file, delete it when the download is complete, then download it again.
you're looking for
while :
do
wget -O - -q "http://some.url/" > /dev/null
done
this will not save the file, not output useless info, and dump the contents over and over again in /dev/null
edit to just consume bandwidth, use ping -f or ping -f -s 65507
If your goal is to max out your bandwidth, especially for the purposes of benchmarking, use iperf. You run iperf on your server and client, and it will test your bandwidth using the protocol and parameters you specify. It can test one-way or two-way throughput and can optionally try to achieve a "target" bandwidth utilization (i.e. 3Mbps).
Everything is possible with programming. :)
If you want to try and max out your internet bandwidth, you could start many many processes of wget and let them download some big disk image files at the same time, while at the same time sending some huge files back to some server.
The details are left for the implementation, but this is one method to max out your bandwidth.
In case you want to consume network bandwidth, you'll need another computer. Then from computer A, IP 192.168.0.1, listen on a port (e.g. 12345).
$ netcat -l -p 12345
Then, from the other computer, send data to it.
$ netcat 192.168.0.1 12345 < /dev/zero
I perfer to use curl to wget. it is more editable. here is an excrpt from a bash script i wrote which checks the SVN version, and then gives the user a choice to download stable or latest. It then parses out the file, separating the "user settings" from the rest of the script.
svnrev=`curl -s -m10 mythicallibrarian.googlecode.com/svn/trunk/| grep -m1 Revision | sed s/"<html><head><title>mythicallibrarian - "/""/g| sed s/": \/trunk<\/title><\/head>"/""/g`
if ! which librarian-notify-send>/dev/null && test "$LinuxDep" = "1"; then
dialog --title "librarian-notify-send" --yesno "install librarian-notify-send script for Desktop notifications?" 8 25
test $? = 0 && DownloadLNS=1 || DownloadLNS=0
if [ "$DownloadLNS" = "1" ]; then
curl "http://mythicallibrarian.googlecode.com/files/librarian-notify-send">"/usr/local/bin/librarian-notify-send"
sudo chmod +x /usr/local/bin/librarian-notify-send
fi
fi
if [ ! -f "./librarian" ]; then
DownloadML=Stable
echo "Stable `date`">./lastupdated
else
lastupdated="`cat ./lastupdated`"
DownloadML=$(dialog --title "Version and Build options" --menu "Download an update first then Build mythicalLibrarian" 10 70 15 "Latest" "Download and switch to SVN $svnrev" "Stable" "Download and switch to last stable version" "Build" "using: $lastupdated" 2>&1 >/dev/tty)
if [ "$?" = "1" ]; then
clear
echo "mythicalLibrarian was not updated."
echo "Please re-run mythicalSetup."
echo "Done."
exit 1
fi
fi
clear
if [ "$DownloadML" = "Stable" ]; then
echo "Stable "`date`>"./lastupdated"
test -f ./mythicalLibrarian.sh && rm -f mythicalLibrarian.sh
curl "http://mythicallibrarian.googlecode.com/files/mythicalLibrarian">"./mythicalLibrarian.sh"
cat "./mythicalLibrarian.sh"| sed s/' '/'\\t'/g |sed s/'\\'/'\\\\'/g >"./mythicalLibrarian1" #sed s/"\\"/"\\\\"/g |
rm ./mythicalLibrarian.sh
mv ./mythicalLibrarian1 ./mythicalLibrarian.sh
parsing="Stand-by Parsing mythicalLibrarian"
startwrite=0
test -f ./librarian && rm -f ./librarian
echo -e 'mythicalVersion="'"`cat ./lastupdated`"'"'>>./librarian
while read line
do
test "$line" = "########################## USER JOBS############################" && let startwrite=$startwrite+1
if [ $startwrite = 2 ]; then
clear
parsing="$parsing""."
test "$parsing" = "Stand-by Parsing mythicalLibrarian......." && parsing="Stand-by Parsing mythicalLibrarian"
echo $parsing
echo -e "$line" >> ./librarian
fi
done <./mythicalLibrarian.sh
clear
echo "Parsing mythicalLibrarian completed!"
echo "Removing old and downloading new version of mythicalSetup..."
test -f ./mythicalSetup.sh && rm -f ./mythicalSetup.sh
curl "http://mythicallibrarian.googlecode.com/files/mythicalSetup.sh">"./mythicalSetup.sh"
chmod +x "./mythicalSetup.sh"
./mythicalSetup.sh
exit 0
fi
if [ "$DownloadML" = "Latest" ]; then
svnrev=`curl -s mythicallibrarian.googlecode.com/svn/trunk/| grep -m1 Revision | sed s/"<html><head><title>mythicallibrarian - "/""/g| sed s/": \/trunk<\/title><\/head>"/""/g`
echo "$svnrev "`date`>"./lastupdated"
test -f ./mythicalLibrarian.sh && rm -f mythicalLibrarian.sh
curl "http://mythicallibrarian.googlecode.com/svn/trunk/mythicalLibrarian">"./mythicalLibrarian.sh"
cat "./mythicalLibrarian.sh"| sed s/' '/'\\t'/g |sed s/'\\'/'\\\\'/g >"./mythicalLibrarian1" #sed s/"\\"/"\\\\"/g |
rm ./mythicalLibrarian.sh
mv ./mythicalLibrarian1 ./mythicalLibrarian.sh
parsing="Stand-by Parsing mythicalLibrarian"
startwrite=0
test -f ./librarian && rm -f ./librarian
echo -e 'mythicalVersion="'"`cat ./lastupdated`"'"'>>./librarian
while read line
do
test "$line" = "########################## USER JOBS############################" && let startwrite=$startwrite+1
if [ $startwrite = 2 ]; then
clear
parsing="$parsing""."
test "$parsing" = "Stand-by Parsing mythicalLibrarian......." && parsing="Stand-by Parsing mythicalLibrarian"
echo $parsing
echo -e "$line" >> ./librarian
fi
done <./mythicalLibrarian.sh
clear
echo "Parsing mythicalLibrarian completed!"
echo "Removing old and downloading new version of mythicalSetup..."
test -f ./mythicalSetup.sh && rm -f ./mythicalSetup.sh
curl "http://mythicallibrarian.googlecode.com/svn/trunk/mythicalSetup.sh">"./mythicalSetup.sh"
chmod +x "./mythicalSetup.sh"
./mythicalSetup.sh
exit 0
fi
EDIT: NEVERMIND I THOUGHT YOU WERE SAYING IT WAS DOWNLOADING IN AN ENDLESS LOOP

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