I have the following bash script:
#!/bin/bash
set command "pgrep -x 'gedit' "
ssh -t test#192.168.94.139 $command
Now, I want to include this as well in the other device:
if pgrep -x "gedit" > /dev/null
then
echo "Running"
else
echo "Not Running"
fi
How can I make the IF Statement run on the other device? I wasn't able to include it in the ssh.
I tried this:
set command "pgrep -x 'gedit' "
ssh -t test#192.168.94.139 '
if pgrep -x "gedit" > /dev/null
then
echo "Running"
else
echo "Not Running"
fi'
But it didn't work! maybe because there is no command at the beginning?
Thanks.
Invoke bash with heredoc:
ssh -t test#192.168.94.139 bash <<EOF
if pgrep -x "gedit" > /dev/null
then
echo "Running"
else
echo "Not Running"
fi
EOF
Related
#!/bin/bash
some_array=($1)
echo "-- Setting-Up VM --"
for i in ${some_array[#]}; do
echo "VM #: $i"
case "$i" in
"1")
echo "Setting-Up VM $i"
sshpass -p "root12" ssh -tt -o StrictHostKeyChecking=no root#10.xx.x.xx <<EOF
pwd
nohup yes | /etc/rc.d/init.d/lifconfig
su tarts
nohup yes | vncserver
sleep 10
exit
exit
EOF
;;
"2")
echo "Setting-Up VM $i"
sshpass -p "root12" ssh -tt -o StrictHostKeyChecking=no root#10.xx.x.xx <<EOF
pwd
nohup yes | /etc/rc.d/init.d/lifconfig
su tarts
nohup yes | vncserver
sleep 10
exit
exit
EOF
;;
"3")
echo "Setting-Up VM $i"
sshpass -p "root12" ssh -tt -o StrictHostKeyChecking=no root#10.xx.x.xx <<EOF
pwd
nohup yes | /etc/rc.d/init.d/lifconfig
su tarts
nohup yes | vncserver
sleep 10
exit
exit
EOF
;;
*)
echo "unknown VM!"
;;
esac
done
Can someone please guide me I have the above script which is executed when we run the script for instance ./vmSetup.sh "1 2 3" but this is executed sequentially. I had created this script but now I want to run the cases in the script i.e. 1, 2 and 3 in parallel. Can someone also tell me how to run for instance 8 cases in parallel?
Put each case ... esac statement in the background by ending it with &. Then use wait after the loop to wait for all the background processes to finish.
#!/bin/bash
some_array=($1)
echo "-- Setting-Up VM --"
for i in ${some_array[#]}; do
echo "VM #: $i"
case "$i" in
"1")
echo "Setting-Up VM $i"
sshpass -p "root12" ssh -tt -o StrictHostKeyChecking=no root#10.xx.x.xx <<EOF
pwd
nohup yes | /etc/rc.d/init.d/lifconfig
su tarts
nohup yes | vncserver
sleep 10
exit
exit
EOF
;;
"2")
echo "Setting-Up VM $i"
sshpass -p "root12" ssh -tt -o StrictHostKeyChecking=no root#10.xx.x.xx <<EOF
pwd
nohup yes | /etc/rc.d/init.d/lifconfig
su tarts
nohup yes | vncserver
sleep 10
exit
exit
EOF
;;
"3")
echo "Setting-Up VM $i"
sshpass -p "root12" ssh -tt -o StrictHostKeyChecking=no root#10.xx.x.xx <<EOF
pwd
nohup yes | /etc/rc.d/init.d/lifconfig
su tarts
nohup yes | vncserver
sleep 10
exit
exit
EOF
;;
*)
echo "unknown VM!"
;;
esac &
done
wait
Why do you have a case statement at all when all these are identical?
#!/bin/bash
echo "-- Setting-Up VM(s) --"
for i in "$#"; do
case "$i" in
1) IP=1.2.3.4;;
2) IP=2.2.3.4;;
3) IP=3.2.3.4;;
*) echo "Invalid option '$i'" >&2; exit 1;;
esac
echo "Setting-Up VM $i"
sshpass -p root12 ssh -tt -o StrictHostKeyChecking=no root#$IP <<EOF &
pwd
nohup yes | /etc/rc.d/init.d/lifconfig
su tarts
nohup yes | vncserver
sleep 10
exit
exit
EOF
done
To run a job in background, just use &
sshpass -p "root12" ssh -tt -o StrictHostKeyChecking=no root#$IP <<EOF &
It's just confusing because of the here-doc, but the & metacharacter still parses correctly on my system. Try it.
Also, rather than quoting all your options in one string and then parsing them back out to an array, why not just simplify the whole thing and let them come in as separate arguments? Call it as
./vmSetup.sh 1 2 3 # NOT "1 2 3" with quotes
and the loop becomes just
for i in "$#" # properly quoted, though wouldn't matter for 1 2 3
This whole thing seems a lot simpler and easier to maintain.
Another option, which is what I would do: create a file that is a list of the DNS/IP addresses you need, then pass that file as the lone argument.
#!/bin/bash
while read -r addr || [[ -n "$addr" ]]
do echo "Setting-Up VM $addr"
sshpass -p "root12" ssh -tt -o StrictHostKeyChecking=no root#$addr <<EOF &
pwd
nohup yes | /etc/rc.d/init.d/lifconfig
su tarts
nohup yes | vncserver
sleep 10
exit
exit
EOF
done < "$1"
Better, add valid error checking first to make sure the file exists and is readable, etc, but as a simple case, this should work.
For even better, cleaner, safer code, read https://mywiki.wooledge.org/BashFAQ/001 and follow those suggestions. :)
If ./vmSetup.sh 1 works as expected, these should work:
parallel -j8 ./vmSetup.sh {} ::: 1 2 3 ... 100
seq 100 | parallel -j8 ./vmSetup.sh
What is the use of bash -c command, while surfing on the internet I came across the command
ssh -t "${SSH_USER}#${SERVER_IP}" bash -c
First part here is doing ssh obviously to a server but what exactly bash -c is responsible for?
bash -c option with ssh is one such method to execute multi line commands on the ssh server with variable expansion.
Say you have
VAR1="Variable 1"
ssh app#HOSTNAME '
ls
pwd
if true; then
echo "True"
echo $VAR1 # <-- it won't work
else
echo "False"
fi
'
But with bash -c
VAR1="Variable 1"
ssh -t "${SSH_USER}#${SERVER_IP}" bash -c "'
ls
pwd
if true; then
echo $VAR1 <-- This works
else
echo "False"
fi
'"
This script required an ip and the script or file that we have to run on the remote server i gave a file in which i have wrote commands like
touch /root/test
ls /root/test
this make the file but do not show and it is displaying an error
tcgetattr: Inappropriate ioctl for device
connection closed
How can I resolve this is there any suggestion ??
#!/bin/bash
# The private key used to identify this machine
IDENTITY_KEY=/home/admnew.pem
syntax()
{
echo "Syntax: Ec2.sh server_ip scriptFile]"
echo "For example: ./Ec2.sh server_ip scriptFile"
exit 1
}
if [ $# -ne 2 ]
then
echo not enough arguments
syntax
fi
echo "Running script $2 on $1"
ssh -t -t -i $IDENTITY_KEY ec2-user#$1 sudo -i 'bash -s' < $2
exit
exit
echo "Done"
Try:
ssh -t -t -i $IDENTITY_KEY ec2-user#$1 sudo -i 'bash -s' <<EOF
(
$(cat "$2")
)
EOF
e.g. wrap the script into (), e.g the:
touch /root/test
ls /root/test
should be
(
touch /root/test
ls /root/test
)
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;;
I'm trying to call a custom shell script through sh:
/bin/sh -c 'myscript.sh` >log.txt 2>&1 & echo $!
Output of this command is a PID of a created background process. I want to instruct /bin/sh to save return code of myscript.sh to some file. Is it possible?
echo $? >> /path/to/return_code
$? has the return code of the last statement in bash.
(/bin/sh -c "myscript.sh" >log.txt 2>&1 ; echo $? >somefile) & echo $!
(
/bin/sh -c 'myscript.sh` >log.txt 2>&1
echo $? > some_file
) &