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10

6

I have numerous linux boxes with a very limited set of commands and disk space. But it has the telnet command on it.

I remotely connect to each of these probes (programmatically) and issue one line linux command through SSH.

I need to run a single command to connect to a specific machine, using telnet, and then disconnect right away.

I can do all that, but the disconnection right away part. Telnet opens some sort of a console, or terminal and I can't figure out a one-line command to run the telnet command and then disconnect right away.

If I do that, I can easily parse the textual output for error messages for not being able to connect to the machine on the specified port and that's exactly what I am looking for.

So how can I run a one-line command to connect to a machine using telnet and disconnect afterwards ?

bash telnet

share|improve this question

edited Aug 15 '18 at 12:41

Muhammad Gelbana

asked Aug 13 '13 at 10:24

Muhammad GelbanaMuhammad Gelbana

61561223

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  As I understand your Telnet client does not support sending directly?
  
  – IBr
  Aug 13 '13 at 11:36
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @IBr, what do you mean ?
  
  – Muhammad Gelbana
  Aug 13 '13 at 12:14
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Note that telent clients differ in exit code reported after client side exit command is used to terminate it. So zero exit code should not be considered a signal the port is opened. Does not work for RHEL telent RPM at least.
  
  – Oliver Gondža
  Jan 6 '17 at 9:59
  

  
  
  
  

add a comment | 

10

6

I have numerous linux boxes with a very limited set of commands and disk space. But it has the telnet command on it.

I remotely connect to each of these probes (programmatically) and issue one line linux command through SSH.

I need to run a single command to connect to a specific machine, using telnet, and then disconnect right away.

I can do all that, but the disconnection right away part. Telnet opens some sort of a console, or terminal and I can't figure out a one-line command to run the telnet command and then disconnect right away.

If I do that, I can easily parse the textual output for error messages for not being able to connect to the machine on the specified port and that's exactly what I am looking for.

So how can I run a one-line command to connect to a machine using telnet and disconnect afterwards ?

bash telnet

share|improve this question

edited Aug 15 '18 at 12:41

Muhammad Gelbana

asked Aug 13 '13 at 10:24

Muhammad GelbanaMuhammad Gelbana

61561223

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  As I understand your Telnet client does not support sending directly?
  
  – IBr
  Aug 13 '13 at 11:36
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @IBr, what do you mean ?
  
  – Muhammad Gelbana
  Aug 13 '13 at 12:14
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Note that telent clients differ in exit code reported after client side exit command is used to terminate it. So zero exit code should not be considered a signal the port is opened. Does not work for RHEL telent RPM at least.
  
  – Oliver Gondža
  Jan 6 '17 at 9:59
  

  
  
  
  

add a comment | 

I have numerous linux boxes with a very limited set of commands and disk space. But it has the telnet command on it.

I remotely connect to each of these probes (programmatically) and issue one line linux command through SSH.

I need to run a single command to connect to a specific machine, using telnet, and then disconnect right away.

I can do all that, but the disconnection right away part. Telnet opens some sort of a console, or terminal and I can't figure out a one-line command to run the telnet command and then disconnect right away.

If I do that, I can easily parse the textual output for error messages for not being able to connect to the machine on the specified port and that's exactly what I am looking for.

So how can I run a one-line command to connect to a machine using telnet and disconnect afterwards ?

bash telnet

share|improve this question

edited Aug 15 '18 at 12:41

Muhammad Gelbana

asked Aug 13 '13 at 10:24

Muhammad GelbanaMuhammad Gelbana

61561223

share|improve this question

edited Aug 15 '18 at 12:41

Muhammad Gelbana

asked Aug 13 '13 at 10:24

Muhammad GelbanaMuhammad Gelbana

61561223

share|improve this question

edited Aug 15 '18 at 12:41

Muhammad Gelbana

asked Aug 13 '13 at 10:24

Muhammad GelbanaMuhammad Gelbana

61561223

asked Aug 13 '13 at 10:24

Muhammad GelbanaMuhammad Gelbana

61561223

asked Aug 13 '13 at 10:24

Muhammad GelbanaMuhammad Gelbana

61561223

6 Answers
6

active

oldest

votes

24

You ought to be able to pipe the exit command into STDIN in telnet.
Try:

echo 'exit' | telnet {site} {port}

and see if that works. (it seems to work on my web server, but YMMV).

share|improve this answer

edited 1 hour ago

Alexander Mills

2,39721962

answered Aug 13 '13 at 17:11

Charles NeweyCharles Newey

40625

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  might work but seems dumb - telnet should have an option to exit or something on first contact
  
  – Alexander Mills
  1 hour ago
  

  
  
  
  

add a comment | 

9

The simplest and easiest method is given below.

 sleep <n> | telnet <server> <port>

n - The wait time in seconds before auto exit. It could be fractional like 0.5. Note that some required output may not be returned in the specified wait time. So we may need to increase accordingly.

server - The target server IP or hostname.

port - Target service port number.

You can also redirect the output to file like this,

sleep 1 | telnet <server> <port> > output.log

share|improve this answer

answered Jun 13 '14 at 12:18

SeffSeff

23024

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  This works perfectly! While the output is indeed redirected, I noticed I still get the "Connection closed by foreign host." output in my console after the sleep rather than in the output.log file. Any way to prevent this?
  
  – dnLL
  Apr 3 at 18:43
  

  
  
  
  

add a comment | 

3

I think better tool for sending commands directly and just getting output would be netcat. It just simple, but powerful tool for putting commands through ports.
You could see usage example in this superuser question: https://superuser.com/questions/261900/how-can-i-pipe-commands-to-a-netcat-that-will-stay-alive - asker gives working example in which connection closes after few seconds.

And if you want just to test connectivity use this:
http://terminalinflection.com/use-netcat-not-telnet-to-test-network-connectivity/

share|improve this answer

edited Mar 20 '17 at 10:18

Community♦

1

answered Aug 13 '13 at 11:41

IBrIBr

1,26031124

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I'm trying to install netcat right now but I'm unable to do so. I downloaded a compiled powerpc version but glibc library was missing. I downloaded a compiled powerpc version but the device didn't have enough space to copy the library files ! Is it possible that the glibc library already exists but netcat can't find it ?
  
  – Muhammad Gelbana
  Aug 13 '13 at 12:13
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Netcat is needed only on client side: on server (probe) can be the same plain old telnet.
  
  – IBr
  Aug 13 '13 at 13:23
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Also Glibc should exist already, it is used on much stuff in usual system.
  
  – IBr
  Aug 13 '13 at 13:28
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  You could try to add to telnet scripts && exit see if it disconnects (in ssh at least it is enough).
  
  – IBr
  Aug 13 '13 at 13:35
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  && exit didn't work. If glibc should exist and I believe it does. Why would nc.traditional complain about it as if it's missing ?
  
  – Muhammad Gelbana
  Aug 13 '13 at 14:38
  

  
  
  
  

 | 
show 1 more comment

1

In my case this works. (CentOs7):

while read host port; do

r=$(bash -c 'exec 3<> /dev/tcp/'$host'/'$port';echo $?' 2>/dev/null)

if [ "$r" = "0" ]; then

     echo "$host $port is open"

else

     echo "$host $port is closed"

     exit 1 # To force fail result in ShellScript

fi

done

:) Regards

share|improve this answer

answered Jan 23 '17 at 21:34

ChussChuss

211

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  Hey, this is great. I am a user on all the Linux systems at my job, but not the admin (and have no admin rights). I'm sick of asking them to install telnet all the time so I can test network connectivity (I'm a network engineer). This is an excellent workaround. I changed it a little to perform more like telnet. I provided my own answer here with the modifications.
  
  – theglossy1
  Nov 22 '17 at 16:39
  

  
  
  
  

add a comment | 

1

This is another version of the answer above that makes it act a little more like "normal" telnet syntax. If you like my answer, please give an upvote not to this, but to the original.

#!/bin/bash

if [ "$2" == "" ]; then

 echo "Syntax: $0 <host> <port>"

 exit;

fi



host=$1

port=$2



r=$(bash -c 'exec 3<> /dev/tcp/'$host'/'$port';echo $?' 2>/dev/null)

if [ "$r" = "0" ]; then

     echo "$host $port is open"

else

     echo "$host $port is closed"

     exit 1 # To force fail result in ShellScript

fi

share|improve this answer

answered Nov 22 '17 at 16:42

theglossy1theglossy1

1113

add a comment | 

0

Here is solution I found on Internet:

( echo open 127.0.0.1 23

sleep 5

echo your_login

sleep 5

echo your_password

sleep 5

echo hostname

sleep 5

echo exit ) | telnet

It works for me on SunOS & HP-UX

share|improve this answer

answered Oct 24 '18 at 21:05

VladimirVladimir

1

add a comment | 

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24

You ought to be able to pipe the exit command into STDIN in telnet.
Try:

echo 'exit' | telnet {site} {port}

and see if that works. (it seems to work on my web server, but YMMV).

share|improve this answer

edited 1 hour ago

Alexander Mills

2,39721962

answered Aug 13 '13 at 17:11

Charles NeweyCharles Newey

40625

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  might work but seems dumb - telnet should have an option to exit or something on first contact
  
  – Alexander Mills
  1 hour ago
  

  
  
  
  

add a comment | 

24

You ought to be able to pipe the exit command into STDIN in telnet.
Try:

echo 'exit' | telnet {site} {port}

and see if that works. (it seems to work on my web server, but YMMV).

share|improve this answer

edited 1 hour ago

Alexander Mills

2,39721962

answered Aug 13 '13 at 17:11

Charles NeweyCharles Newey

40625

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  might work but seems dumb - telnet should have an option to exit or something on first contact
  
  – Alexander Mills
  1 hour ago
  

  
  
  
  

add a comment | 

You ought to be able to pipe the exit command into STDIN in telnet.
Try:

echo 'exit' | telnet {site} {port}

and see if that works. (it seems to work on my web server, but YMMV).

share|improve this answer

edited 1 hour ago

Alexander Mills

2,39721962

answered Aug 13 '13 at 17:11

Charles NeweyCharles Newey

40625

echo 'exit' | telnet {site} {port}

share|improve this answer

edited 1 hour ago

Alexander Mills

2,39721962

answered Aug 13 '13 at 17:11

Charles NeweyCharles Newey

40625

edited 1 hour ago

Alexander Mills

2,39721962

edited 1 hour ago

Alexander Mills

2,39721962

answered Aug 13 '13 at 17:11

Charles NeweyCharles Newey

40625

answered Aug 13 '13 at 17:11

Charles NeweyCharles Newey

40625

9

The simplest and easiest method is given below.

 sleep <n> | telnet <server> <port>

n - The wait time in seconds before auto exit. It could be fractional like 0.5. Note that some required output may not be returned in the specified wait time. So we may need to increase accordingly.

server - The target server IP or hostname.

port - Target service port number.

You can also redirect the output to file like this,

sleep 1 | telnet <server> <port> > output.log

share|improve this answer

answered Jun 13 '14 at 12:18

SeffSeff

23024

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  This works perfectly! While the output is indeed redirected, I noticed I still get the "Connection closed by foreign host." output in my console after the sleep rather than in the output.log file. Any way to prevent this?
  
  – dnLL
  Apr 3 at 18:43
  

  
  
  
  

add a comment | 

9

The simplest and easiest method is given below.

 sleep <n> | telnet <server> <port>

n - The wait time in seconds before auto exit. It could be fractional like 0.5. Note that some required output may not be returned in the specified wait time. So we may need to increase accordingly.

server - The target server IP or hostname.

port - Target service port number.

You can also redirect the output to file like this,

sleep 1 | telnet <server> <port> > output.log

share|improve this answer

answered Jun 13 '14 at 12:18

SeffSeff

23024

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  This works perfectly! While the output is indeed redirected, I noticed I still get the "Connection closed by foreign host." output in my console after the sleep rather than in the output.log file. Any way to prevent this?
  
  – dnLL
  Apr 3 at 18:43
  

  
  
  
  

add a comment | 

The simplest and easiest method is given below.

 sleep <n> | telnet <server> <port>

n - The wait time in seconds before auto exit. It could be fractional like 0.5. Note that some required output may not be returned in the specified wait time. So we may need to increase accordingly.

server - The target server IP or hostname.

port - Target service port number.

You can also redirect the output to file like this,

sleep 1 | telnet <server> <port> > output.log

share|improve this answer

answered Jun 13 '14 at 12:18

SeffSeff

23024

 sleep <n> | telnet <server> <port>

sleep 1 | telnet <server> <port> > output.log

share|improve this answer

answered Jun 13 '14 at 12:18

SeffSeff

23024

answered Jun 13 '14 at 12:18

SeffSeff

23024

answered Jun 13 '14 at 12:18

SeffSeff

23024

3

I think better tool for sending commands directly and just getting output would be netcat. It just simple, but powerful tool for putting commands through ports.
You could see usage example in this superuser question: https://superuser.com/questions/261900/how-can-i-pipe-commands-to-a-netcat-that-will-stay-alive - asker gives working example in which connection closes after few seconds.

And if you want just to test connectivity use this:
http://terminalinflection.com/use-netcat-not-telnet-to-test-network-connectivity/

share|improve this answer

edited Mar 20 '17 at 10:18

Community♦

1

answered Aug 13 '13 at 11:41

IBrIBr

1,26031124

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I'm trying to install netcat right now but I'm unable to do so. I downloaded a compiled powerpc version but glibc library was missing. I downloaded a compiled powerpc version but the device didn't have enough space to copy the library files ! Is it possible that the glibc library already exists but netcat can't find it ?
  
  – Muhammad Gelbana
  Aug 13 '13 at 12:13
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Netcat is needed only on client side: on server (probe) can be the same plain old telnet.
  
  – IBr
  Aug 13 '13 at 13:23
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Also Glibc should exist already, it is used on much stuff in usual system.
  
  – IBr
  Aug 13 '13 at 13:28
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  You could try to add to telnet scripts && exit see if it disconnects (in ssh at least it is enough).
  
  – IBr
  Aug 13 '13 at 13:35
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  && exit didn't work. If glibc should exist and I believe it does. Why would nc.traditional complain about it as if it's missing ?
  
  – Muhammad Gelbana
  Aug 13 '13 at 14:38
  

  
  
  
  

 | 
show 1 more comment

3

I think better tool for sending commands directly and just getting output would be netcat. It just simple, but powerful tool for putting commands through ports.
You could see usage example in this superuser question: https://superuser.com/questions/261900/how-can-i-pipe-commands-to-a-netcat-that-will-stay-alive - asker gives working example in which connection closes after few seconds.

And if you want just to test connectivity use this:
http://terminalinflection.com/use-netcat-not-telnet-to-test-network-connectivity/

share|improve this answer

edited Mar 20 '17 at 10:18

Community♦

1

answered Aug 13 '13 at 11:41

IBrIBr

1,26031124

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I'm trying to install netcat right now but I'm unable to do so. I downloaded a compiled powerpc version but glibc library was missing. I downloaded a compiled powerpc version but the device didn't have enough space to copy the library files ! Is it possible that the glibc library already exists but netcat can't find it ?
  
  – Muhammad Gelbana
  Aug 13 '13 at 12:13
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Netcat is needed only on client side: on server (probe) can be the same plain old telnet.
  
  – IBr
  Aug 13 '13 at 13:23
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Also Glibc should exist already, it is used on much stuff in usual system.
  
  – IBr
  Aug 13 '13 at 13:28
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  You could try to add to telnet scripts && exit see if it disconnects (in ssh at least it is enough).
  
  – IBr
  Aug 13 '13 at 13:35
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  && exit didn't work. If glibc should exist and I believe it does. Why would nc.traditional complain about it as if it's missing ?
  
  – Muhammad Gelbana
  Aug 13 '13 at 14:38
  

  
  
  
  

 | 
show 1 more comment

I think better tool for sending commands directly and just getting output would be netcat. It just simple, but powerful tool for putting commands through ports.
You could see usage example in this superuser question: https://superuser.com/questions/261900/how-can-i-pipe-commands-to-a-netcat-that-will-stay-alive - asker gives working example in which connection closes after few seconds.

And if you want just to test connectivity use this:
http://terminalinflection.com/use-netcat-not-telnet-to-test-network-connectivity/

share|improve this answer

edited Mar 20 '17 at 10:18

Community♦

1

answered Aug 13 '13 at 11:41

IBrIBr

1,26031124

share|improve this answer

edited Mar 20 '17 at 10:18

Community♦

1

answered Aug 13 '13 at 11:41

IBrIBr

1,26031124

edited Mar 20 '17 at 10:18

Community♦

1

edited Mar 20 '17 at 10:18

Community♦

1

answered Aug 13 '13 at 11:41

IBrIBr

1,26031124

answered Aug 13 '13 at 11:41

IBrIBr

1,26031124

1

In my case this works. (CentOs7):

while read host port; do

r=$(bash -c 'exec 3<> /dev/tcp/'$host'/'$port';echo $?' 2>/dev/null)

if [ "$r" = "0" ]; then

     echo "$host $port is open"

else

     echo "$host $port is closed"

     exit 1 # To force fail result in ShellScript

fi

done

:) Regards

share|improve this answer

answered Jan 23 '17 at 21:34

ChussChuss

211

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  Hey, this is great. I am a user on all the Linux systems at my job, but not the admin (and have no admin rights). I'm sick of asking them to install telnet all the time so I can test network connectivity (I'm a network engineer). This is an excellent workaround. I changed it a little to perform more like telnet. I provided my own answer here with the modifications.
  
  – theglossy1
  Nov 22 '17 at 16:39
  

  
  
  
  

add a comment | 

1

In my case this works. (CentOs7):

while read host port; do

r=$(bash -c 'exec 3<> /dev/tcp/'$host'/'$port';echo $?' 2>/dev/null)

if [ "$r" = "0" ]; then

     echo "$host $port is open"

else

     echo "$host $port is closed"

     exit 1 # To force fail result in ShellScript

fi

done

:) Regards

share|improve this answer

answered Jan 23 '17 at 21:34

ChussChuss

211

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  Hey, this is great. I am a user on all the Linux systems at my job, but not the admin (and have no admin rights). I'm sick of asking them to install telnet all the time so I can test network connectivity (I'm a network engineer). This is an excellent workaround. I changed it a little to perform more like telnet. I provided my own answer here with the modifications.
  
  – theglossy1
  Nov 22 '17 at 16:39
  

  
  
  
  

add a comment | 

In my case this works. (CentOs7):

while read host port; do

r=$(bash -c 'exec 3<> /dev/tcp/'$host'/'$port';echo $?' 2>/dev/null)

if [ "$r" = "0" ]; then

     echo "$host $port is open"

else

     echo "$host $port is closed"

     exit 1 # To force fail result in ShellScript

fi

done

:) Regards

share|improve this answer

answered Jan 23 '17 at 21:34

ChussChuss

211

while read host port; do

r=$(bash -c 'exec 3<> /dev/tcp/'$host'/'$port';echo $?' 2>/dev/null)

if [ "$r" = "0" ]; then

     echo "$host $port is open"

else

     echo "$host $port is closed"

     exit 1 # To force fail result in ShellScript

fi

done

share|improve this answer

answered Jan 23 '17 at 21:34

ChussChuss

211

answered Jan 23 '17 at 21:34

ChussChuss

211

answered Jan 23 '17 at 21:34

ChussChuss

211

1

This is another version of the answer above that makes it act a little more like "normal" telnet syntax. If you like my answer, please give an upvote not to this, but to the original.

#!/bin/bash

if [ "$2" == "" ]; then

 echo "Syntax: $0 <host> <port>"

 exit;

fi



host=$1

port=$2



r=$(bash -c 'exec 3<> /dev/tcp/'$host'/'$port';echo $?' 2>/dev/null)

if [ "$r" = "0" ]; then

     echo "$host $port is open"

else

     echo "$host $port is closed"

     exit 1 # To force fail result in ShellScript

fi

share|improve this answer

answered Nov 22 '17 at 16:42

theglossy1theglossy1

1113

add a comment | 

1

This is another version of the answer above that makes it act a little more like "normal" telnet syntax. If you like my answer, please give an upvote not to this, but to the original.

#!/bin/bash

if [ "$2" == "" ]; then

 echo "Syntax: $0 <host> <port>"

 exit;

fi



host=$1

port=$2



r=$(bash -c 'exec 3<> /dev/tcp/'$host'/'$port';echo $?' 2>/dev/null)

if [ "$r" = "0" ]; then

     echo "$host $port is open"

else

     echo "$host $port is closed"

     exit 1 # To force fail result in ShellScript

fi

share|improve this answer

answered Nov 22 '17 at 16:42

theglossy1theglossy1

1113

add a comment | 

This is another version of the answer above that makes it act a little more like "normal" telnet syntax. If you like my answer, please give an upvote not to this, but to the original.

#!/bin/bash

if [ "$2" == "" ]; then

 echo "Syntax: $0 <host> <port>"

 exit;

fi



host=$1

port=$2



r=$(bash -c 'exec 3<> /dev/tcp/'$host'/'$port';echo $?' 2>/dev/null)

if [ "$r" = "0" ]; then

     echo "$host $port is open"

else

     echo "$host $port is closed"

     exit 1 # To force fail result in ShellScript

fi

share|improve this answer

answered Nov 22 '17 at 16:42

theglossy1theglossy1

1113

#!/bin/bash

if [ "$2" == "" ]; then

 echo "Syntax: $0 <host> <port>"

 exit;

fi



host=$1

port=$2



r=$(bash -c 'exec 3<> /dev/tcp/'$host'/'$port';echo $?' 2>/dev/null)

if [ "$r" = "0" ]; then

     echo "$host $port is open"

else

     echo "$host $port is closed"

     exit 1 # To force fail result in ShellScript

fi

share|improve this answer

answered Nov 22 '17 at 16:42

theglossy1theglossy1

1113

answered Nov 22 '17 at 16:42

theglossy1theglossy1

1113

answered Nov 22 '17 at 16:42

theglossy1theglossy1

1113

0

Here is solution I found on Internet:

( echo open 127.0.0.1 23

sleep 5

echo your_login

sleep 5

echo your_password

sleep 5

echo hostname

sleep 5

echo exit ) | telnet

It works for me on SunOS & HP-UX

share|improve this answer

answered Oct 24 '18 at 21:05

VladimirVladimir

1

add a comment | 

0

Here is solution I found on Internet:

( echo open 127.0.0.1 23

sleep 5

echo your_login

sleep 5

echo your_password

sleep 5

echo hostname

sleep 5

echo exit ) | telnet

It works for me on SunOS & HP-UX

share|improve this answer

answered Oct 24 '18 at 21:05

VladimirVladimir

1

add a comment | 

Here is solution I found on Internet:

( echo open 127.0.0.1 23

sleep 5

echo your_login

sleep 5

echo your_password

sleep 5

echo hostname

sleep 5

echo exit ) | telnet

It works for me on SunOS & HP-UX

share|improve this answer

answered Oct 24 '18 at 21:05

VladimirVladimir

1

( echo open 127.0.0.1 23

sleep 5

echo your_login

sleep 5

echo your_password

sleep 5

echo hostname

sleep 5

echo exit ) | telnet

share|improve this answer

answered Oct 24 '18 at 21:05

VladimirVladimir

1

answered Oct 24 '18 at 21:05

VladimirVladimir

1

answered Oct 24 '18 at 21:05

VladimirVladimir

1