I have a pipeline that open a ssh connection on target and then I need to run some command.
...
sh'''ssh -T '''+server''' << EOF
ls -la
var=$(grep 'test' /etc/passwd | awk -F'' '{print $2}'
echo $var
EOF
'''
var is always empty...
Someone has an idea?
Related
I have a small shell script as follows that I am using to login to multiple servers to capture whether the target server is using Redhat or Ubuntu as the OS version.
#!/bin/ksh
if [ -f $HOME/osver.report.txt ];then
rm -rf $HOME/osver.report.txt
fi
for x in `cat hostlist`
do
OSVER=$(ssh $USER#${x} "cat /etc/redhat-release 2>/dev/null || grep -i DISTRIB_DESCRIPTION /etc/lsb-release 2>/dev/null")
echo -e "$x \t\t $OSVER" >> osver.report.txt
done
The above script works, however, if I attempt to add in some awk as shown below and the server is a redhat server...my results in the osver.report.txt will only show the hostname and no OS version. I have played around with the quoting, but nothing seems to work.
OSVER=$(ssh $USER#${x} "cat /etc/redhat-release | awk {'print $1,$2,$6,$7'} 2>/dev/null || grep -i DISTRIB_DESCRIPTION /etc/lsb-release 2>/dev/null")
If I change the script as suggested to the following:
#!/bin/bash
if [ -f $HOME/osver.report.txt ];then
rm -rf $HOME/osver.report.txt
fi
for x in cat hostlist
do
OSVER=$(
ssh $USER#${x} bash << 'EOF'
awk '{print "$1,$2,$6,$7"}' /etc/redhat-release 2>/dev/null || grep -i DISTRIB_DESCRIPTION /etc/lsb-release 2>/dev/null
EOF
)
echo -e "$x \t\t $OSVER" >> osver.report.txt
done
Then I get the following errors:
./test.bash: line 9: unexpected EOF while looking for matching `)'
./test.bash: line 16: syntax error: unexpected end of file
You're suffering from a quoting problem. When you pass a quoted command to ssh, you effectively lose one level of quoting (as if you passed the same arguments to sh -c "..."). So the command that you're running on the remote host is actually:
cat /etc/redhat-release | awk '{print ,,,}' | grep -i DISTRIB_DESCRIPTION /etc/lsb-release
One way of resolving this is to pipe your script into a shell, rather than passing it as arguments:
OSVER=$(
ssh $USER#${x} bash <<'EOF'
awk '{print "$1,$2,$6,$7"}' /etc/redhat-release 2>/dev/null ||
grep -i DISTRIB_DESCRIPTION /etc/lsb-release 2>/dev/null
EOF
)
The use of <<'EOF' here inhibits any variable expansion in the here document...without that, expressions like $1 would be expanded locally.
A better solution would be to look into something like ansible which has built-in facilities for sshing to groups of hosts and collecting facts about them, including distribution version information.
Hope this time it's not a duplicate. I didn't find anything.
My code:
#!/bin/bash
FILE=/home/user/srv.txt
TICKET=task
while read LINE; do
ssh -nT $LINE << 'EOF'
touch info.txt
hostname >> info.txt
ifconfig | grep inet | awk '$3 ~ "cast" {print $2}' >> info.txt
grep -i ^server /etc/zabbix/zabbix_agentd.conf >> info.txt
echo "- Done -" >> info.txt
EOF
ssh -nT $LINE "cat info.txt" >> $TICKET.txt
done < $FILE #End
My issue:
if I only use ssh $LINE it will only ssh to the host on the first line and also display an error Pseudo-terminal will not be allocated because stdin is not a terminal.
using ssh -T , fix the error message above and it will create the file info.txt
using ssh -nT , fix the error where ssh only read the first line but I get an error message cat: info.txt: No such file or directory. If I ssh to the hosts, I can confirm that there is no info.txt file in my home folder. and with ssh -T, I have this file in my home folder.
I tried with the option -t, also HERE, EOF without ' ... ' but no luck
Do I miss something?
Thanks for your help,
Iswaren
You have two problems.
If you invoke ssh without -n it may consume the $FILE input (it drains its stdin)
If you invoke ssh with -n it won't read its stdin, so none of the commands will be executed
However, the first ssh has had its input redirected to come from a heredoc, so it does not need -n.
As stated in the comments, the second ssh call is not needed. Rather than piping into info.txt and then copying that into a local file, just output to the local file directly:
while read LINE; do
ssh -T $LINE >>$TICKET.txt <<'EOF'
hostname
ifconfig | grep inet | awk '$3 ~ "cast" {print $2}'
grep -i ^server /etc/zabbix/zabbix_agentd.conf
echo "- Done -"
EOF
done <$FILE
The uncommented line complains that 'mus' file doesn't doesn't exist, whereas the commented line behaves as expected and gives me the number of lines in 'mus' file
vr=$(ssh $1 "cd $2; count=`cat mus | wc -l`; echo $count")
#vr=$(ssh $1 "cd $2; cat mus | wc -l")
echo $vr
The uncommented line is looking for file mus on your local system, whereas the commented one looks on the remote system. You need to escape the backticks and the $ in the count variable for this to work:
vr=$(ssh $1 "cd $2; count=\`cat mus | wc -l\`; echo \$count")
echo $vr
You'll be getting this error:
cat: mus: No such file or directory
Reason is this command
count=`cat mus | wc -l`
is getting executed locally not on remote host.
To execute multiple commands on remote host use here-doc:
ssh -t -t "$1"<<EOF
cd "$2"
c=\$(wc -l < mus)
echo \$c
exit
EOF
Hi I want grep all aliases and run their "body"
alias | grep NAME
it's return:
alias NAME123='ping google123.com'
alias NAME321='ping google321.com'
...
I want to run:
ping google123.com
ping google321.com
but not
NAME123
NAME321
All my tries ended syntax mistake.
write_aliases_script.sh
#!/bin/bash
printf "#!/bin/bash\n\n" 1>script.sh;
alias | grep NAME |
grep -o "'\(.\+\)'" |
sed "s/'//g" 1>>script.sh;
chmod +x script.sh;
# uncomment after testing
#./script.sh;
output
$ ./write_aliases_script.sh
$ cat script.sh
#!/bin/bash
ping google123.com
ping google321.com
Using eval you can make it run but be careful to not to invoke risky aliases:
eval $(alias | awk -F "'" '/NAME/{print $2}')
This question already has answers here:
Execute a command on remote hosts via ssh from inside a bash script
(4 answers)
Closed 7 years ago.
I need a help with a bash script that connect to server as root, execute some commands and then exit from the server.
I tried this script but when login login to server performed the command not running !
#!/bin/bash
sudo ssh -o ConnectTimeout=10 $1 'exit'
if [ $? != 0 ]; then
echo "Could not connect to $1 , script stopped"
exit
fi
sudo ssh $1
echo "SRV=`cat /etc/puppet/puppet.conf | grep -i srv_domain | awk '{print $3}'`"
echo $SRV
echo "puppetMaster=`host -t srv _x-puppet._tcp.$SRV | head -1 | awk '{print $8}' | cut -f1 -d"."`"
echo $puppetMaster
'exit'
I'm surprised nobody has suggested a heredoc yet.
sudo ssh "$1" <<'EOF'
SRV=`cat /etc/puppet/puppet.conf | grep -i srv_domain | awk '{print $3}'`
echo $SRV
echo "puppetMaster=`host -t srv _x-puppet._tcp.$SRV | head -1 | awk '{print $8}' | cut -f1 -d"."`"
echo $puppetMaster
EOF
This feeds everything from the <<'EOF' until the line starting with EOF into the stdin of ssh, to be received and run by the remote shell.
The commands following ssh machine in a script are not run on the machine. They will be run on the local machine once the ssh exits.
Either specify the commands to run as an argument of ssh, or alternatively, run ssh and make it read the commands from standard input, and send the commands to it.
ssh machine ls
# or
echo ls | ssh machine
You seem to be a little confused as to what runs where.
ssh -o ConnectTimeout=10 $1 'exit'
will connect to $1, run exit, and disconnect.
ssh -o ConnectTimeout=10 $1 'echo hello world'
will print hello world on
the server and then disconnect.
ssh $1
will open up a shell on the remote. After the shell has ended, the following commands will run locally.
echo "SRV=`cat /etc/puppet/puppet.conf | grep -i srv_domain | awk '{print $3}'`"
echo $SRV
echo "puppetMaster=`host -t srv _x-puppet._tcp.$SRV | head -1 | awk '{print $8}' | cut -f1 -d"."`"
echo $puppetMaster
'exit'
What you probably want is start bash on the remote and forward to it the commands you want to give it via stdin.
echo "my commands" | ssh $1 bash
Technically, you don't need that bash -- ssh will start bash even without it (but with different rc files).