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Questions tagged [telnet]

Telnet is a protocol for bidirectional interactive text-oriented communication with remote hosts via virtual terminals. It is defined in [RFC 854](http://tools.ietf.org/html/rfc854). Telnet provides no inherent security and so is becoming less commonly supported. On modern UNIX-like systems it is usually replaced with more secure and flexible [SSH](/tags/ssh/info) protocol.

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32 views

Is Telnet able to check a specified IP address? [closed]

I'm using Telnet to check if my server has the required ports open, but after getting the telnet: Unable to connect to remote host: Connection refused error with every port I want to verify if the ...
0
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1answer
52 views

How can I abort a telnet connection attempt? [closed]

Suppose I execute the following in command prompt: telnet XXX.XXX.XXX.XXX 80 half a second later, I realize it would never connect (for whatever reason). I want to abort the connection attempt ...
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1answer
39 views

Why do we need the host name again when downloading the webpage by using telnet?

I learned you could use telnet to download a webpage(making http request), like telnet www.example.com 80 GET HTTP / HTTP/1.1 HOST: www.example.com then the output would be an html source page or ...
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1answer
119 views

Why smtp server can not be telnet?

https://www.webdigi.co.uk/blog/2009/how-to-check-if-an-email-address-exists-without-sending-an-email/ I am following the above instruction to telnet an email server of gmail. But I got an error. ...
0
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1answer
185 views

EXIM SMTP allows to send mails without login / authentication via telnet to any domain

I'm ashamed, but I have to ask for help. My server is being used for sending spam, I've found out I can simply connect with telnet (edit: from any server in office, home and even directly from CMD/...
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0answers
37 views

How to set the mode of port? access, trunk, general

I tried to set (change) the mode of my port, and I read the book and followed it step by step. But I still get a lot of error. There were what I input. (Routing) (Interface 0/3)#switchport mode ...
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0answers
14 views

Custom Keyboard Hotkey in CentOS terminal

I'm trying to replace old serial terminals with CentOS PCs. I have got the PC's to use telnet (this will be changing to SSH soon) to connect to the server and everything works nearly identically to ...
0
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1answer
107 views

How can I enable SMTP receipt through firewalld on Linux?

I've leased a dedicated, lightly-managed CentOS7 box from a hosting company. The host came with firewalld installed and running and with its iptables preferences pre-imposed. I was not expecting ...
0
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2answers
368 views

Is there a security risk to just having the telnet client installed on Windows?

I was recently asking for the telnet client to be turned on on my Windows install. The devops guy told me it was restricted because it passed people's usernames and passwords through clear text. I ...
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0answers
115 views

SSH and Telnet connectivity issues. It connects sometimes and sometimes it does not

I have come across a problem with SSH and Telnet wherein the connectivity is slow and drops multiple times. But I see that my network has no problems. When I ping a server, it gives me ttl of 127, ...
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0answers
168 views

telnet 3-Way Handshake

I'm trying to see a simple 3-Way Handshake using telnet on the Client side and tcpdump on the Server side, both Client and Server are inside VMs. I use telnet this way : telnet 172.10.10.21 80 On ...
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0answers
89 views

Busybox Long Delay after Login (Telnet Port 23)

I'm logging into a BusyBox system. If i login through telnet, after i enter my password, it hangs for 15 seconds before giving me the command prompt. If i login through SSH, after i enter my ...
3
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2answers
539 views

telnet non interactive: connection closed by foreign host

if I do telnet host_ip port < /dev/null Trying host_ip... Connected to host_ip. Escape character is '^]'. Connection closed by foreign host. By checking the wireshark, the client side sends tcp ...
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1answer
302 views

Telnet through a serial terminal server

I have a Perle IOLAN device like this, and one configuration option is for a serial terminal. The corresponding configuration screen. As you can see, one option is to configure the terminal to ...
1
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1answer
318 views

Telnet SMTP gives OK but not accepted or queued message and mails not received

I am trying to debug a CDO.Message.1 error '80040213', The transport failed to connect to the server. So I am testing the connection to the SMTP server via telnet. After entering the DATA I am ...
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1answer
2k 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 ...
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1answer
3k views

telnet: Unable to connect to remote host: Connection timed out

Setting up a postfix server, trying to figure out why it's not working. Here's a command that I ran while troubleshooting. I expected to be able to connect, but could not. lol@foldingmachine:~$ ...
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2answers
57 views

How can I run an interactive console program when a user connects via SSH

Looking to start a python program when a user connects to my SSH server. An example use case would be a MUD program (except using SSH and not Telnet). If they somehow exit the program or it errors out,...
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0answers
458 views

Check if HTTP Methods have been Allowed and Enabled on Localhost

I’m running Apache/2.2.15 (Unix) on a RHEL system. My LAMP is running on localhost. I want to check if the HTTP methods: POST, GET, PUT and DELETE are allowed and enabled. I’ve read that ...
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0answers
121 views

OpenVPN connected, partial internet [IPv6]

I've got an OpenVPN server set up and it works wonderfully, with all internet traffic using the VPN connection. On one specific WiFi network, I can use telnet/openssl s_client to connect to web ...
1
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1answer
27 views

Unable to telnet particular server IP from our CentOS 7.2 server

I am unable to telnet a partner server IP (103.x.x.x) from our server. I am getting following error telnet: connect to address 103.x.x.x: Connection timed out but I am able to telnet other server ...
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1answer
2k views

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 ...
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2answers
444 views

Linux - opened port, but still fail to connect to it using telnet

I'm currently working on CentOS 7.3. In order to activate SNMP, I installed it, configured it and successfully started the service using the firewall-cmd command. Now, I realized that I need to ...
0
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1answer
288 views

Amazon EC2 Ubuntu 16.04 telnet works on some ports and not for others

I am having a strange issue on my newly installed Amazon Ec2 ubuntu 16.04 LTS server. I have a server with ip (10.129.29.46) in a VPC which has the following ports open 80, 443, 11300 and 9000. Port ...
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0answers
104 views

SSH or telnet on other ports is not working from a specific network

We have an Lenovo server working well since one and a half year. Sudenly, we started having issues to connect to it from our office network. I reinstalled ubuntu 16.04 sever on it. It has two ethernet ...
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1answer
28 views

Exchange 2016 is ignoring a single host for SMTP/EWS

We've just completed a deployment and migration from Exchange 2010 to Exchange 2016. Our ticket system connects to an Exchange mailbox to generate tickets. Connections from the ticket system to ...
0
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1answer
406 views

Unable to telnet at port 80 AWS EC2 instance

I have allowed port 80 on my ec2 instance, and this is my iptables rules on it Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD (policy DROP) ...
0
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2answers
540 views

Server remote MySQL connection not working after PHP upgrade from 5.4 to 5.6

MySQL remote connections used to work ok. Now it's not working anymore and we think it may be related to a PHP upgrade from 5.4 to 5.6. I did a script to test this connection: $db = @mysql_connect('...
0
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2answers
580 views

Local Server with external IP not reachable when in LAN

I have a local debain server with external IP and my own domain. But I got following problem: Using DNS/external IP from outside the LAN: Works Using local IP from inside the LAN: Works Using DNS/...
0
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2answers
481 views

How do I find out why port 8172 is blocked?

We have some web sites hosted with a third-party company, and wish to use web deploy. They have told us that we need to ensure that port 8172 is open, as that is needed. As a test, they gave us a URL ...
0
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1answer
100 views

Windows port will not open in google compute engine

I've added a firewall rule in GCE udp:5585;tcp:5585 in my networking config. I've also added an inbound rule in Windows to accept both udp and tcp connections on port 5585. I'm trying to set this up ...
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1answer
164 views

POP3 Server: ERR Unsupported authentication type

I've installed Axigen Mail Server and enabled SMTP and POP3 servers. After that, I've created domain (slava.local) and an user (slava). So now I can connect to the SMTP server (using telnet, open ...
0
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2answers
412 views

use multiple ip addresses to tcp check remote server's port

Im trying to tcp connect yahoo's mail server on port 25 . I have 3 public ip addresses lets say:- (all are allowed in SPF records) 99.99.99.99 77.77.77.77 88.88.88.88 How to telnet(or other checks) ...
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0answers
95 views

DKIM Key validation fails when using Mail Command

I have a relay server that I am using to send emails. I am signing outbound emails using dkim. When I send the mail using telnet the gmail logs look like this: Received-SPF: pass (google.com: domain ...
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1answer
3k 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 ...
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1answer
519 views

telnet to Yandex's smtp port wont work on Google Cloud Plaltform [closed]

I'm trying to send mail on my server which on located on vps in Google Cloud. I can telnet to gmail's SMTP both 587/465 but i can't connect via telnet to Yandex. It's stucking on Trying .... # ...
0
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1answer
87 views

Unable to connect VPS server hosted node js code to another provider MYSQL server

I have just bought the unmanaged VPS. I am running a node js application that uses a connection string for mysql database stored somewhere else. The connection between vps (nodejs web) and mysql ...
0
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1answer
90 views

Random domain when using telnet on my server's IP

I was preparing a new website on my cloud server and before changing the domain's pointing IP I decided to use telnet to make a quick test. Since each site is a vhost I can use a different domain (...
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1answer
505 views

Disable SSH version info on Telnet [duplicate]

I need to disable SSH information while telnet to SSH port in CentOS. telnet 192.168.10.192 22 Trying 192.168.10.192... Connected to 192.168.10.192. Escape character is '^]'. SSH-2.0-OpenSSH_6.4 ...
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2answers
281 views

Cancel Telnet prompt WITHOUT closing connection?

I opened a Telnet connection from a Linux machine, and hit Ctrl + ] to bring up the telnet> prompt. How do I drop out of this prompt and go back to my session without closing the Telnet connection? ...
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1answer
704 views

Third party trying to test LDAP(s) port on our server

So we've been trying to set up an LDAP sync with an outside vendor. We have a Cisco ASA, which I'm fairly confident is configured correctly as far as NAT/PAT goes. I also opened the ports on the ...
1
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0answers
106 views

POP3 service is not ready even though the service is running, Telnet does not return POP3 OK status?

I am working on a Windows 2008 R2 server running Exchange 2010 and I am currently trying to troubleshoot a POP3 connectivity issue that is preventing some outside remote accounts from logging into the ...
0
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2answers
218 views

Pulling from GitHub to IIS

To update my website I need to pull from GitHub to IIS, remotely, not by using RDP. How can I do that? TelNet does not support git and I don't like installing OpenSSH ( it needs CygWin)
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1answer
78 views

Trying to set up mail forwarding via postfix on Debian - cannot make telnet connection on port 25

So I've been working on this problem for a few days and I'm at a loss. I have installed postfix on Debian with the intent of setting up some forwarding addresses for a specific domain. I believe that ...
0
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1answer
468 views

Missing or skipped ICMP_Seq In AIX Ping

I noticed an intermittent slow response on the ping from my application server to my database server. So to diagnose, I tested using a standard ping and Telnet tests. For the telnet tests, it was ...
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1answer
5k views

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,...
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1answer
220 views

remote host can't send mail using sendmail in ubuntu

I have followed the below steps to configure sendmail apt-get install sendmail add the below content in /etc/mail/auth/client-info AuthInfo:<gworks.yyy> "U:<mail@gworks.yyy>" "I:<...
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1answer
228 views

How to get telnet working in SCO openserver release 3.2v5.0.6?

I have a sco box (SCO openserver release 3.2v5.0.6) and I went and changed the ip address of the server via netconfig. Sadly, telnet is no longer working when I attempt it from another computer to ...
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2answers
252 views

not getting the response from the webserver for the request GET / [closed]

When I telnet my server it is getting connected, however after telnet connection if I request for GET /, it is not giving any response. But, after telnet connection if I request for GET / HTTP/1.1, it ...
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1answer
81 views

SSH & Telnet work, then don't

I have a very tiny network in one room, with one Fedora laptop connected to a Dell PowerEdge server with CentOS. They communicate through an unmanaged wired Ethernet switch, which itself is connected ...