Telnet connection stops bash script
I have a bash script where I continuously read from a text file the hosts and port and create a connection to check for the status.
My code is:
while IFS=";" read -r host ports
do
eval "arr=($ports)"
for port in "${arr[@]}";
do
echo "connecting to $host on port $port" >> output.txt
timeout 5s telnet $host $port
exit_status=$?
if [[ $exit_status -eq 124 ]]; then
echo "$host on $port has timed out" >> output.txt
else
telnet $host $port >> output.txt
fi
echo "---------------------------------------------" >> output.txt
done
done < "$1"
The first if is to check if the connection timeouts.
That works as expected.
In the else block the script exits if the connection has been established. I am not sure why this happens.
It stops by spitting out:
Escape character is '^]'.
Connection closed by foreign host.
I am looking for it to write to the output file status of the connection.
bash shell-script telnet
asked 1 hour ago
Ronakh Thaikkat
101
New contributor
Ronakh Thaikkat is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
I have a bash script where I continuously read from a text file the hosts and port and create a connection to check for the status.
My code is:
while IFS=";" read -r host ports
do
eval "arr=($ports)"
for port in "${arr[@]}";
do
echo "connecting to $host on port $port" >> output.txt
timeout 5s telnet $host $port
exit_status=$?
if [[ $exit_status -eq 124 ]]; then
echo "$host on $port has timed out" >> output.txt
else
telnet $host $port >> output.txt
fi
echo "---------------------------------------------" >> output.txt
done
done < "$1"
The first if is to check if the connection timeouts.
That works as expected.
In the else block the script exits if the connection has been established. I am not sure why this happens.
It stops by spitting out:
Escape character is '^]'.
Connection closed by foreign host.
I am looking for it to write to the output file status of the connection.
bash shell-script telnet
asked 1 hour ago
Ronakh Thaikkat
101
New contributor
Ronakh Thaikkat is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
What do you mean, "file status"? You've determined that the port didn't time out, but what's the point of thetelnetconnection? Are you hoping to establish a connection and execute a command?
– Jeff Schaller
56 mins ago
add a comment |
I have a bash script where I continuously read from a text file the hosts and port and create a connection to check for the status.
My code is:
while IFS=";" read -r host ports
do
eval "arr=($ports)"
for port in "${arr[@]}";
do
echo "connecting to $host on port $port" >> output.txt
timeout 5s telnet $host $port
exit_status=$?
if [[ $exit_status -eq 124 ]]; then
echo "$host on $port has timed out" >> output.txt
else
telnet $host $port >> output.txt
fi
echo "---------------------------------------------" >> output.txt
done
done < "$1"
The first if is to check if the connection timeouts.
That works as expected.
In the else block the script exits if the connection has been established. I am not sure why this happens.
It stops by spitting out:
Escape character is '^]'.
Connection closed by foreign host.
I am looking for it to write to the output file status of the connection.
bash shell-script telnet
asked 1 hour ago
Ronakh Thaikkat
101
New contributor
Ronakh Thaikkat is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I have a bash script where I continuously read from a text file the hosts and port and create a connection to check for the status.
My code is:
while IFS=";" read -r host ports
do
eval "arr=($ports)"
for port in "${arr[@]}";
do
echo "connecting to $host on port $port" >> output.txt
timeout 5s telnet $host $port
exit_status=$?
if [[ $exit_status -eq 124 ]]; then
echo "$host on $port has timed out" >> output.txt
else
telnet $host $port >> output.txt
fi
echo "---------------------------------------------" >> output.txt
done
done < "$1"
The first if is to check if the connection timeouts.
That works as expected.
In the else block the script exits if the connection has been established. I am not sure why this happens.
It stops by spitting out:
Escape character is '^]'.
Connection closed by foreign host.
I am looking for it to write to the output file status of the connection.
bash shell-script telnet
bash shell-script telnet
asked 1 hour ago
Ronakh Thaikkat
101
New contributor
Ronakh Thaikkat is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 1 hour ago
Ronakh Thaikkat
101
New contributor
Ronakh Thaikkat is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 1 hour ago
Ronakh Thaikkat
101
New contributor
Ronakh Thaikkat is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 1 hour ago
Ronakh Thaikkat
101
asked 1 hour ago
Ronakh Thaikkat
101
101
New contributor
Ronakh Thaikkat is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Ronakh Thaikkat is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Ronakh Thaikkat is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
What do you mean, "file status"? You've determined that the port didn't time out, but what's the point of thetelnetconnection? Are you hoping to establish a connection and execute a command?
– Jeff Schaller
56 mins ago
add a comment |
What do you mean, "file status"? You've determined that the port didn't time out, but what's the point of thetelnetconnection? Are you hoping to establish a connection and execute a command?
– Jeff Schaller
56 mins ago
What do you mean, "file status"? You've determined that the port didn't time out, but what's the point of the
telnet connection? Are you hoping to establish a connection and execute a command?– Jeff Schaller
56 mins ago
What do you mean, "file status"? You've determined that the port didn't time out, but what's the point of the
telnet connection? Are you hoping to establish a connection and execute a command?– Jeff Schaller
56 mins ago
add a comment |
1 Answer
1
active
oldest
votes
Both telnet commands will attempt to read from the remains of your $1 file, whatever that may be. So your loop may get executed an unexpectedly fewer number of times.
I'm not sure what input you were expecting to provide to telnet though.
Incidentally, if you have it installed you'd be better off using netcat (sometimes known as nc). It won't solve it change the input issue but it is usually a better tool for this kind of scripted interaction.
answered 57 mins ago
roaima
42.8k551116
add a comment |
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1 Answer
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1 Answer
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active
oldest
votes
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Both telnet commands will attempt to read from the remains of your $1 file, whatever that may be. So your loop may get executed an unexpectedly fewer number of times.
I'm not sure what input you were expecting to provide to telnet though.
Incidentally, if you have it installed you'd be better off using netcat (sometimes known as nc). It won't solve it change the input issue but it is usually a better tool for this kind of scripted interaction.
answered 57 mins ago
roaima
42.8k551116
add a comment |
Both telnet commands will attempt to read from the remains of your $1 file, whatever that may be. So your loop may get executed an unexpectedly fewer number of times.
I'm not sure what input you were expecting to provide to telnet though.
Incidentally, if you have it installed you'd be better off using netcat (sometimes known as nc). It won't solve it change the input issue but it is usually a better tool for this kind of scripted interaction.
answered 57 mins ago
roaima
42.8k551116
add a comment |
Both telnet commands will attempt to read from the remains of your $1 file, whatever that may be. So your loop may get executed an unexpectedly fewer number of times.
I'm not sure what input you were expecting to provide to telnet though.
Incidentally, if you have it installed you'd be better off using netcat (sometimes known as nc). It won't solve it change the input issue but it is usually a better tool for this kind of scripted interaction.
answered 57 mins ago
roaima
42.8k551116
Both telnet commands will attempt to read from the remains of your $1 file, whatever that may be. So your loop may get executed an unexpectedly fewer number of times.
I'm not sure what input you were expecting to provide to telnet though.
Incidentally, if you have it installed you'd be better off using netcat (sometimes known as nc). It won't solve it change the input issue but it is usually a better tool for this kind of scripted interaction.
answered 57 mins ago
roaima
42.8k551116
edited 32 mins ago
answered 57 mins ago
roaima
42.8k551116
answered 57 mins ago
roaima
42.8k551116
answered 57 mins ago
roaima
42.8k551116
42.8k551116
add a comment |
add a comment |
Ronakh Thaikkat is a new contributor. Be nice, and check out our Code of Conduct.
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What do you mean, "file status"? You've determined that the port didn't time out, but what's the point of the
telnetconnection? Are you hoping to establish a connection and execute a command?– Jeff Schaller
56 mins ago