Ubuntu Telnet problem

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1
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I have a problem with Ubuntu 14.04. I am a student of microcomputer systems and networks.



I have a virtual machine running Ubuntu 14.04 and when trying to connect to localhost with telnet, the following happens:



$ telnet localhost
Connection closed with foreign host



linux ubuntu telnet




share|improve this question





















  • You should show the exact command that you are using to make the connection. Also mention what you expect to happen. Is there or should there be anything listening for a telnet connection on the port that you connect to?
    – Kusalananda
    Jun 7 at 10:00










  • Use 'telnet localhost', i hope to start sessión in telnet.
    – Mireia
    Jun 7 at 10:10






  • 3




    Do you have a Telnet server installed? (Most modern operating systems do not install Telnet servers by default.)
    – AlexP
    Jun 7 at 10:14










  • telnet localhost will connect you your local system on port 23 by default unless you mentioned port no., like telnet localhost 22
    – Naushad Ahmad
    Jun 7 at 10:14






  • 1




    Yes, i have instaled Telnet and the port used for Telnet is 23.
    – Mireia
    Jun 7 at 10:22














up vote
1
down vote

favorite












I have a problem with Ubuntu 14.04. I am a student of microcomputer systems and networks.



I have a virtual machine running Ubuntu 14.04 and when trying to connect to localhost with telnet, the following happens:



$ telnet localhost
Connection closed with foreign host



linux ubuntu telnet




share|improve this question





















  • You should show the exact command that you are using to make the connection. Also mention what you expect to happen. Is there or should there be anything listening for a telnet connection on the port that you connect to?
    – Kusalananda
    Jun 7 at 10:00










  • Use 'telnet localhost', i hope to start sessión in telnet.
    – Mireia
    Jun 7 at 10:10






  • 3




    Do you have a Telnet server installed? (Most modern operating systems do not install Telnet servers by default.)
    – AlexP
    Jun 7 at 10:14










  • telnet localhost will connect you your local system on port 23 by default unless you mentioned port no., like telnet localhost 22
    – Naushad Ahmad
    Jun 7 at 10:14






  • 1




    Yes, i have instaled Telnet and the port used for Telnet is 23.
    – Mireia
    Jun 7 at 10:22












up vote
1
down vote

favorite









up vote
1
down vote

favorite











I have a problem with Ubuntu 14.04. I am a student of microcomputer systems and networks.



I have a virtual machine running Ubuntu 14.04 and when trying to connect to localhost with telnet, the following happens:



$ telnet localhost
Connection closed with foreign host



linux ubuntu telnet




share|improve this question













I have a problem with Ubuntu 14.04. I am a student of microcomputer systems and networks.



I have a virtual machine running Ubuntu 14.04 and when trying to connect to localhost with telnet, the following happens:



$ telnet localhost
Connection closed with foreign host




linux ubuntu telnet





share|improve this question












share|improve this question




share|improve this question








edited Jun 7 at 12:57
























asked Jun 7 at 9:59









Mireia

92




92











  • You should show the exact command that you are using to make the connection. Also mention what you expect to happen. Is there or should there be anything listening for a telnet connection on the port that you connect to?
    – Kusalananda
    Jun 7 at 10:00










  • Use 'telnet localhost', i hope to start sessión in telnet.
    – Mireia
    Jun 7 at 10:10






  • 3




    Do you have a Telnet server installed? (Most modern operating systems do not install Telnet servers by default.)
    – AlexP
    Jun 7 at 10:14










  • telnet localhost will connect you your local system on port 23 by default unless you mentioned port no., like telnet localhost 22
    – Naushad Ahmad
    Jun 7 at 10:14






  • 1




    Yes, i have instaled Telnet and the port used for Telnet is 23.
    – Mireia
    Jun 7 at 10:22
















  • You should show the exact command that you are using to make the connection. Also mention what you expect to happen. Is there or should there be anything listening for a telnet connection on the port that you connect to?
    – Kusalananda
    Jun 7 at 10:00










  • Use 'telnet localhost', i hope to start sessión in telnet.
    – Mireia
    Jun 7 at 10:10






  • 3




    Do you have a Telnet server installed? (Most modern operating systems do not install Telnet servers by default.)
    – AlexP
    Jun 7 at 10:14










  • telnet localhost will connect you your local system on port 23 by default unless you mentioned port no., like telnet localhost 22
    – Naushad Ahmad
    Jun 7 at 10:14






  • 1




    Yes, i have instaled Telnet and the port used for Telnet is 23.
    – Mireia
    Jun 7 at 10:22















You should show the exact command that you are using to make the connection. Also mention what you expect to happen. Is there or should there be anything listening for a telnet connection on the port that you connect to?
– Kusalananda
Jun 7 at 10:00




You should show the exact command that you are using to make the connection. Also mention what you expect to happen. Is there or should there be anything listening for a telnet connection on the port that you connect to?
– Kusalananda
Jun 7 at 10:00












Use 'telnet localhost', i hope to start sessión in telnet.
– Mireia
Jun 7 at 10:10




Use 'telnet localhost', i hope to start sessión in telnet.
– Mireia
Jun 7 at 10:10




3




3




Do you have a Telnet server installed? (Most modern operating systems do not install Telnet servers by default.)
– AlexP
Jun 7 at 10:14




Do you have a Telnet server installed? (Most modern operating systems do not install Telnet servers by default.)
– AlexP
Jun 7 at 10:14












telnet localhost will connect you your local system on port 23 by default unless you mentioned port no., like telnet localhost 22
– Naushad Ahmad
Jun 7 at 10:14




telnet localhost will connect you your local system on port 23 by default unless you mentioned port no., like telnet localhost 22
– Naushad Ahmad
Jun 7 at 10:14




1




1




Yes, i have instaled Telnet and the port used for Telnet is 23.
– Mireia
Jun 7 at 10:22




Yes, i have instaled Telnet and the port used for Telnet is 23.
– Mireia
Jun 7 at 10:22










1 Answer
1






active

oldest

votes

















up vote
-1
down vote













Open port no. 23 on ufw by giving below command :



sudo ufw allow 23


If ufw is not installed then first install it by issuing below command and then try again the above command :



sudo apt-get install ufw


Now, you can connect with telnet localhost






share|improve this answer





















  • I do what you say and nothing :(
    – Mireia
    Jun 7 at 10:53










  • cal you telnet localhost 22?
    – Naushad Ahmad
    Jun 7 at 10:55






  • 1




    It is rare for firewalls to block local connections to localhost.
    – Kusalananda
    Jun 7 at 10:55










  • @Mireia are you getting Protocal mismatch before connection closed by foreign host?
    – Naushad Ahmad
    Jun 7 at 10:57










  • that means you are getting connected, once you will type something after that, it will give 'Protocol Mismatch' and pressing Enter key several time will give 'Connection closed by foreign host'. This is actually not a problem. It works like that.
    – Naushad Ahmad
    Jun 7 at 11:25










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1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes








up vote
-1
down vote













Open port no. 23 on ufw by giving below command :



sudo ufw allow 23


If ufw is not installed then first install it by issuing below command and then try again the above command :



sudo apt-get install ufw


Now, you can connect with telnet localhost






share|improve this answer





















  • I do what you say and nothing :(
    – Mireia
    Jun 7 at 10:53










  • cal you telnet localhost 22?
    – Naushad Ahmad
    Jun 7 at 10:55






  • 1




    It is rare for firewalls to block local connections to localhost.
    – Kusalananda
    Jun 7 at 10:55










  • @Mireia are you getting Protocal mismatch before connection closed by foreign host?
    – Naushad Ahmad
    Jun 7 at 10:57










  • that means you are getting connected, once you will type something after that, it will give 'Protocol Mismatch' and pressing Enter key several time will give 'Connection closed by foreign host'. This is actually not a problem. It works like that.
    – Naushad Ahmad
    Jun 7 at 11:25














up vote
-1
down vote













Open port no. 23 on ufw by giving below command :



sudo ufw allow 23


If ufw is not installed then first install it by issuing below command and then try again the above command :



sudo apt-get install ufw


Now, you can connect with telnet localhost






share|improve this answer





















  • I do what you say and nothing :(
    – Mireia
    Jun 7 at 10:53










  • cal you telnet localhost 22?
    – Naushad Ahmad
    Jun 7 at 10:55






  • 1




    It is rare for firewalls to block local connections to localhost.
    – Kusalananda
    Jun 7 at 10:55










  • @Mireia are you getting Protocal mismatch before connection closed by foreign host?
    – Naushad Ahmad
    Jun 7 at 10:57










  • that means you are getting connected, once you will type something after that, it will give 'Protocol Mismatch' and pressing Enter key several time will give 'Connection closed by foreign host'. This is actually not a problem. It works like that.
    – Naushad Ahmad
    Jun 7 at 11:25












up vote
-1
down vote










up vote
-1
down vote









Open port no. 23 on ufw by giving below command :



sudo ufw allow 23


If ufw is not installed then first install it by issuing below command and then try again the above command :



sudo apt-get install ufw


Now, you can connect with telnet localhost






share|improve this answer













Open port no. 23 on ufw by giving below command :



sudo ufw allow 23


If ufw is not installed then first install it by issuing below command and then try again the above command :



sudo apt-get install ufw


Now, you can connect with telnet localhost







share|improve this answer













share|improve this answer



share|improve this answer











answered Jun 7 at 10:48









Naushad Ahmad

1409




1409











  • I do what you say and nothing :(
    – Mireia
    Jun 7 at 10:53










  • cal you telnet localhost 22?
    – Naushad Ahmad
    Jun 7 at 10:55






  • 1




    It is rare for firewalls to block local connections to localhost.
    – Kusalananda
    Jun 7 at 10:55










  • @Mireia are you getting Protocal mismatch before connection closed by foreign host?
    – Naushad Ahmad
    Jun 7 at 10:57










  • that means you are getting connected, once you will type something after that, it will give 'Protocol Mismatch' and pressing Enter key several time will give 'Connection closed by foreign host'. This is actually not a problem. It works like that.
    – Naushad Ahmad
    Jun 7 at 11:25
















  • I do what you say and nothing :(
    – Mireia
    Jun 7 at 10:53










  • cal you telnet localhost 22?
    – Naushad Ahmad
    Jun 7 at 10:55






  • 1




    It is rare for firewalls to block local connections to localhost.
    – Kusalananda
    Jun 7 at 10:55










  • @Mireia are you getting Protocal mismatch before connection closed by foreign host?
    – Naushad Ahmad
    Jun 7 at 10:57










  • that means you are getting connected, once you will type something after that, it will give 'Protocol Mismatch' and pressing Enter key several time will give 'Connection closed by foreign host'. This is actually not a problem. It works like that.
    – Naushad Ahmad
    Jun 7 at 11:25















I do what you say and nothing :(
– Mireia
Jun 7 at 10:53




I do what you say and nothing :(
– Mireia
Jun 7 at 10:53












cal you telnet localhost 22?
– Naushad Ahmad
Jun 7 at 10:55




cal you telnet localhost 22?
– Naushad Ahmad
Jun 7 at 10:55




1




1




It is rare for firewalls to block local connections to localhost.
– Kusalananda
Jun 7 at 10:55




It is rare for firewalls to block local connections to localhost.
– Kusalananda
Jun 7 at 10:55












@Mireia are you getting Protocal mismatch before connection closed by foreign host?
– Naushad Ahmad
Jun 7 at 10:57




@Mireia are you getting Protocal mismatch before connection closed by foreign host?
– Naushad Ahmad
Jun 7 at 10:57












that means you are getting connected, once you will type something after that, it will give 'Protocol Mismatch' and pressing Enter key several time will give 'Connection closed by foreign host'. This is actually not a problem. It works like that.
– Naushad Ahmad
Jun 7 at 11:25




that means you are getting connected, once you will type something after that, it will give 'Protocol Mismatch' and pressing Enter key several time will give 'Connection closed by foreign host'. This is actually not a problem. It works like that.
– Naushad Ahmad
Jun 7 at 11:25












 

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