Questions tagged [telnet]
For questions about Telnet, a protocol for bidirectional interactive text-oriented communication with remote hosts via virtual terminals. It is defined in RFC 854.
336
questions
308
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8
answers
1.4m
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Check if port is open or closed on a Linux server?
How can I check if a port is listening on a Linux server?
- 3,247
50
votes
6
answers
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How to check that an OpenVPN server is listening on a remote port without using OpenVPN client?
I need to check that an OpenVPN (UDP) server is up and accessible on a given host:port.
I only have a plain Windows XP computer with no OpenVPN client (and no chance to install it) and no keys needed ...
- 3,398
44
votes
10
answers
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keyboard shortcut to quit 'telnet'
on Windows XP/server 2003
When telnet some remote host on a specified port, after connection established, sometimes press ctrl+] doesn't quit. Is there any command can quit instead of just close the ...
- 1,397
30
votes
7
answers
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something like telnet, but "listen on", not "connect to"
With the telnet program one can connect to any TCP port on any host, but is there a way to listen on some port on current host?
i.e.
1) on host a:
telnet listen 12345
2) on host b:
telnet host_a ...
- 301
27
votes
9
answers
3k
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Is packet sniffing for passwords on a fully switched network really a concern?
I administer a number of linux servers that require telnet access for users.
Currently the user's credentials are stored locally on each server and the passwords tend to be very weak and there is no ...
- 390
25
votes
3
answers
89k
views
How to test a connection without telnet? [closed]
I'm trying to test whether machine A can connect to machine B on certain ports. The sysadmins of machine A have seen fit to remove the telnet command. What would be a convenient replacement? Machine A ...
- 5,910
20
votes
3
answers
8k
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How to kill a telnet client with rlwrap since ^] does not work?
When I use telnet with rlwrap it looks like there is no way to kill the client. Am I missing something here or I really have to kill the process with the kill command?
- 585
16
votes
2
answers
90k
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invoking telnet from two different interfaces
I use telnet to test email server connectivity between servers.
My server has two interfaces, I'd like to telnet over each.
Basically I'd like to choose source (one of my local ip addresses) AND ...
16
votes
9
answers
85k
views
Send an email with an attached file using telnet or netcat
I often use telnet or netcat to connect smtp servers to send an email as a test.
Does anyone know how you would send an email using telnet or netcat but attach a file as well? There are probably ...
- 84.4k
16
votes
2
answers
116k
views
Verify connectivity to a server on a UDP port
I want to know if a HP-UX machine can communicate to a remote machine (which I don't have control over) on a particular port using UDP.
I tried telnet, but it doesn't look like it supports UDP. I ...
- 789
16
votes
1
answer
21k
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How to determine if google public stun server is alive or usable? [closed]
I have seen a lot of of WebRTC client libraries using public STUN server like below:
"stun.l.google.com:19302",
"stun1.l.google.com:19302",
"stun2.l.google.com:19302", ...
- 955
16
votes
1
answer
22k
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How to check postfix server using telnet
I have postfix email server on Ubuntu 11.04 version. I upgraded installed packages using the following command
sudo aptitude update && sudo aptitude safe-upgrade
Once I update those packages,...
- 269
14
votes
3
answers
69k
views
Contacting DNS server via command line interface [closed]
So, we are on the DNS chapter in our class, and I was wondering if there's any way possible though which I can connect to a DNS server on port 53 via command line interface (i.e Telnet or netcat) like ...
- 265
12
votes
6
answers
49k
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Windows Server 2008 without telnet client - how to test connecting to remote ports without installing anything new?
I'm looking to see if anyone knows of slick tricks to test connections to remote server ports from Windows server 2008 and variants that don't include the telnet client installed by default. Reason ...
- 267
12
votes
3
answers
149k
views
"-bash: telnet: command not found " error?
I have the following services running:
sshd 0:off 1:off 2:on 3:on 4:on 5:on 6:off
syslog 0:off 1:off 2:on 3:on 4:on 5:on 6:off
tcsd 0:...
- 125
11
votes
3
answers
8k
views
How to quit QEMU monitor?
I launched KVM VM with this command:
kvm /kvm/hdd/v1/v1-1.raw -m 512 -daemonize -smp 2 -nographic -net nic,model=virtio,macaddr=aa:aa:aa:aa:aa:01 -net tap,ifname=tap0 -monitor telnet:localhost:7001,...
- 596
8
votes
6
answers
29k
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Can the Windows telnet client be scripted?
Is it possible to use the Windows Telnet client to run a series of commands in a script?
If not are there any alternatives that can be?
- 183
8
votes
2
answers
14k
views
Enabling the telnet client for all Windows 7 PCs on a domain
The telnet client is disabled by default in Windows 7. I would like to enable the telnet client for all Windows 7 PCs in our domain. I know how to enable it manually:
Start
Control Panel
Programs And ...
- 1,183
7
votes
3
answers
14k
views
Send test mail using telnet via smtps (465) port
Based on this guide I am trying to send a test email using telnet from linux
https://linuxconfig.org/send-an-email-using-telnet
but the connection immediately disconnects:
$ telnet smtp.gmail.com 465
...
- 277
7
votes
1
answer
52k
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Telnet Results in "Connection closed by foreign host"
I'm not a networking guy, so I apologize if my question is dumb.
I have two Ubuntu machines setup on Amazon EC2. I need to "talk" from one to the other via port 9300. On my receiving machine, I ran ...
- 73
7
votes
6
answers
3k
views
Windows server and telnet, what can you do?
On a Windows Server 2008, can you even telnet into the server? (not remote desktop, but via the command line)
If yes, is there much control really?
How do people automate if you can't telnet? (...
- 2,901
7
votes
5
answers
18k
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"No route to host" with ssl but not with telnet
I have a strange problem with connecting to a https site from one of my servers.
When I type:
telnet puppet 8140
I am presented with a standard telnet console and can talk to the Server as always:
...
- 315
6
votes
2
answers
2k
views
Confusion over terminology SSH, Shell, Terminal, Command Prompt and Telnet
I don't usually use SSH if I can get away with it, but if I have to I do of course, and I've seemingly done this for years while still managing to remain slightly confused about these different terms ....
- 190
6
votes
3
answers
3k
views
Running a shell script for certain user who logs in with SSH
First time here and posting just because I can't seem to find the answer to this, or whether is this even possible.
The problem I'm having is that I want to create a script that will be run ...
- 63
6
votes
4
answers
44k
views
how to check connectivity to server by windows tools?
I need to check if client can connect to server on specific TCP port. Server is listening on it. Tried "telnet server_IP port" but telnet is stuck when I see that it's connected to the server. Seems ...
- 197
6
votes
1
answer
14k
views
Use telnet to check that VNC port is open
I am supposed to connect to a Mac VNC/ARD server. Let's say that the Mac VNC server has the hypothetical IP address 8.8.8.8.
I want to check if the Mac VNC server even listens to the default VNC port ...
- 159
6
votes
2
answers
19k
views
Windows/Linux socat to share a serial device over IP
I have a scenario where I demonstrated to my group @ work how to share a very expensive USB patient simulator plugged into a Raspberry Pi (Debian) using socat. The group wants to be able to have an on-...
- 61
5
votes
5
answers
625
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If I use ftp or telnet by accident, to what extent is my password unsafe?
if i use ftp or telnet by accident (usually on the bash shell), to what extend is my password visible?
can my coworker see it?
can my neighbor see it if i work at home (if not using wireless)?
can ...
- 535
5
votes
4
answers
38k
views
Best Method to test Opened Ports [closed]
We have a requirment where in we have to test 500+ Port opening rules. So requires a suggest on below points.
Which is the best tool to test the connectivity of the ports. Telnet will be sufficient
...
- 185
5
votes
3
answers
4k
views
How do I restore (xterm|gnome-terminal) wrapping after telnet to HP equipment has messed it up?
I telnet to an HP switch from my (xterm|gnome-terminal). Exit telnet. That breaks the behaviour of the terminal. (If you don't have a HP switch to telnet to, one can cat this file in a terminal ...
- 872
5
votes
6
answers
10k
views
How to customize telnet login prompt on linux
When I run login command on debian, I get:
hostname login: _
on RHEL5, Solaris or HP-UX I get:
login: _
I need to be able to customize login: and password: prompts it on a Linux box. I can ...
- 856
5
votes
2
answers
892
views
What are the reasons for using telnet command?
I SSH into root and noticed the previous user used this command:
telnet randomdomain.com 25
From what I gathered it is connecting to another server? But that domain doesn't have anything to do with ...
- 151
5
votes
2
answers
35k
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Why am I unable to telnet to a local port that has a listening service?
I suspect this is either a very simple question, or a very complex one.
I have a headless server running ubuntu 10.04 that I can ssh into. I have full root access to the system. I am trying to set up ...
- 171
5
votes
2
answers
10k
views
Can't connect to SMTP server
I have trouble connecting to an SMTP server from my PC.
I use Debian sid.
telnet mail.example.com 25
Trying 12.23.34.45...
telnet: Unable to connect to remote host: Connection timed out
While from ...
- 53
4
votes
8
answers
15k
views
How to start a Windows GUI app from telnet
I have a GUI application running on a windows XP client machine. I would like to telnet in, shut it down, pull some files over via ftp and then start it up again.
It's that last part that I'm having ...
- 489
4
votes
3
answers
30k
views
telnet source IP
I have a multihomed Windows 2003 server. Is there a way to specify the source IP address to use with the telnet client?
- 178
4
votes
4
answers
5k
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Telnet connection to an AS400 system via telnetlib (Python)
I use telnetlib - Python - to create a telnet client - port 23 - to communicate with an AS/400 server. communication with the telnet command that is no problem, but with telnetlib I do not get any ...
- 143
4
votes
3
answers
2k
views
Automation in Windows Instances on Amazon EC2
I am working on a compute service that will require automatic deployment of our software (~30 megs). The software is a WCF service, so I am stuck with windows. I can't use mono because we use lots of ...
- 135
4
votes
2
answers
32k
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How do I fix "getaddrinfo: localhost Name or service not found" for telnet server?
I need to enable telnet (no i can't use ssh, and I don't want to discuss why I have to use telnet either), I have 127.0.0.1 localhost.localdomain localhost in /etc/hosts. I have installed telnet-...
- 679
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1
answer
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Can I use HAProxy to load balance telnet connections?
We use HAProxy as load balancer for regular HTTP requests. I see no reference to telnet connections in the HAProxy configuration guide: HAProxy config guide.
I was hoping to reuse HAProxy (or spin up ...
- 157
4
votes
2
answers
21k
views
Unable to telnet out on port 25 on windows server 2008
I just setup a Windows 2008 R2 server and am trying to get a basic mail server up and running so that I can send emails from my applications.
I setup a virtual SMTP server in IIS6 and tried doing a ...
- 143
4
votes
4
answers
17k
views
How to forward UDP Wake-on-Lan port to broadcast IP with IPTABLES?
I'm trying to setup Wake-on-Lan for some of the LAN computers at home and it seems that I need to open a UDP port (7 or 9 being the most common) and forward all requests to the broadcast IP, which in ...
- 1,000
3
votes
5
answers
967
views
Why does anyone use ftp?
I am a newbie, so maybe I'm missing something. Why would anyone use ftp or telnet for site administration? If they use them, why would they wonder how they've been hacked? Isn't it obvious that all ...
- 725
3
votes
2
answers
2k
views
Output text file to TCP port
How can I output a text file to a TCP port on Windows Vista using built-in software? For example,
type TextFile.csv | telnet localhost 1979
This doesn't work: The process tried to write to a ...
- 185
3
votes
3
answers
485
views
Is is possible to reattach a telnet connection?
Our network involves a series of dumb text terminals which telnet into a SCO OpenServer 6 server. Occasionally, one of these terminals will crash, forcing the operator to move to a different terminal ...
- 1,106
3
votes
1
answer
11k
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Connecting to Hotmail's IMAP Server using Telnet [closed]
Hotmail appears to have two separate IMAP ports:
imap-mail.outlook.com 993
And:
imap-mail.outlook.com 143
My guess here is that 143 is unsecured, and 993 is over SSL. However, when I try to ...
- 215
3
votes
1
answer
8k
views
Sending an email with an attachment using telnet and ESMTP protocol [closed]
I would like to send an email using ESMTP protocol and attach a file to the email.
I have no errors when sending regular email, I only have problem with attachments.
Here's what I use for sending ...
- 65
3
votes
2
answers
9k
views
telnet connection refused despite ufw having ports open [closed]
How is this possible? I dont understand
Server A ip=111.111.111.111
Server B ip=222.222.222.222
Server A:
ufw status
23 ALLOW 222.222.222.222
9160 ...
- 336
3
votes
2
answers
237
views
Why does telnet send a RSET when I control-c while connecting?
Solaris 10 using snoop to capture packets.
When I telnet to an unused IP address, and wait for the connection attempt to time out, everything behaves as expected (SYNs sent several times until ...
- 683
3
votes
3
answers
12k
views
Connecting to a LDAPS server
I am working on a development machine and I am trying to connect to my LDAP server. This is what I do -
telnet ldaps- 686
then the response is -
Could not open connection to the host
on ...
- 141