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11

It's for convenience, but it's also a lower-than-user-level diagnostic. You can isolate the problem you're having with a service that way, for example: Joe has a database server and client. They are not communicating. Is the problem on the network? The server? The client? Joe goes to the client machine and opens a shell. He uses telnet, just as you ...


11

With socat (a 'bidirectional data relay between two data channels') you can can connect to the unix domain socket like this: $ socat - UNIX-CONNECT:/tmp/memcached.sock


8

With netcat-openbsd, there is a -U option. If you don't have it, you probably have netcat-traditional installed instead; I'd suggest switching.


8

You can use socat on Debian. To install it: # apt-get install socat


8

Check the file /etc/ttys which contains list of terminals. Only those marked "secure" will allow root to login. By default this is the console and all virtual terminals. Pseudo terminals do not allow root login. Also, in this day and age, where security is a big concern, may I ask why you are still using an unsecure protocol like telnet and not ssh ? ...


7

Telnet is a very simple protocol, where everything that you type in your client (with few exceptions) go to the wire, and everything that comes from the wire is shown in your terminal. The exception is the 0xFF byte, that setups some special communication states. As long as your communication doesn't contain this byte, you can use telnet as sort of a raw ...


7

Instead of manually specifying the fingerprint (which can change), you can instead tell offlineimap where your local system certificates are stored and then have it automatically verify the chain. [Repository somerepos-remote] type = Gmail sslcacertfile = /etc/ssl/certs/ca-certificates.crt The sslcacertfile is what does the trick. If non-Ubuntu users ...


7

Create a user and set his login shell to your command. For example: sudo apt-get install sl sudo adduser foo sudo chsh -s $(which sl) foo ssh foo@localhost Also have a look at man sshd_config for some other ways to configure you ssh server. (Like adding a ForceCommand.)


5

A more general solution than Laurentiu Roescu's would be to use iptables, which works the same in every distribution and essentially regardless of which software is installed. # iptables -A INPUT -p tcp -s <ip_address> --dport telnet -j DROP You may optionally use -j REJECT instead of -j DROP. Using REJECT will tell whoever is at the other end that ...


4

Just wanted to mention that (at least on Ubuntu 12.04) there is --askpass /your/file argument for openvpn, that reads the private key password from a file.


4

So here are in one answer a summary of my comments. You have 3 solutions depending on your environment: A. Your Windows host is connected to a network 1- Use "Bridge networking" And select the Windows network interface that is configured under Windows to have network access. Make sure you have no firewall on Ubuntu: sudo iptables -L should give you no ...


4

In /etc/host.deny add: telnet: <ip_addres> But you should use ssh instead.


3

You can use Proxychains for this. First install proxychains, using the command: $ apt-get install proxychains Then configure your proxy settings in /etc/proxychains.conf file. Add at last, these lines for HTTP and HTTPS proxy. http proxy-ip proxy-port username password https proxy-ip proxy-port username password Now you ...


3

You could do what the browser does, i.e. connect to the proxy, $ telnet proxy-server 3128 and talk to it. If there was no authentication, a simple GET request (followed by two newlines (Enter)) with a full hostname and protocol, e.g. GET http://www.google.com/ HTTP/1.1 should suffice. Since you need authentication, you need to provide your username ...


3

telnet reads from ~/.telnetrc at startup, but that won't help you with typing long hostnames. For that you should make yourself some shell functions like this: t1 () { telnet foo.bar.blat; } t2 () { telnet crock.fook.ack; } t3 () { ... and so on... } Put them in your .bashrc, or .zshrc or whatever your shell reads at startup and then type t1 when you ...


3

Why exactly can you connect via telnet to smtp port for example? Because both smtp and telnet protocols are implemented as plain-text. So with a telnet client, you can basically go connect to any port with a specific protocol that implements plain-text and you know how to communicate using the protocol.


3

You need to set up an SSH server on the linux machine first, search google for step-by-step instructions. Then, yes, use the IP address.


3

Server listens on port 8000: $ nc -l 8000 Client connects to port 8000: $ nc localhost 8000


3

On the first question, maybe the service does not wait for interactive input. There could be other explanations, too. On the second, nmap can be used to test the firewall. There are many options. Scan the first 1,000 ports (default): nmap -v -A -PN hostname.domainname.com Or perhaps a specific range: nmap -v -A -p 10000-11000 -PN ...


3

socat(1) could be of some help. From http://stuff.mit.edu/afs/sipb/machine/penguin-lust/src/socat-1.7.1.2/EXAMPLES: // poor mans 'telnetd' replacement # socat tcp-l:2023,reuseaddr,fork exec:/bin/login,pty,setsid,setpgid,stderr,ctty // and here an appropriate client: $ socat -,raw,echo=0 tcp:172.16.181.130:2023 Here, the example uses "login" which ...


3

If you are asking "What is the way to connect to an SMTP server using SSH instead of telnet?" the answer is there is none. SSH only communicates over ports using the SSH protocol. Using it to connect to any other port will fail, because SSH will try to speak the SSH protocol, which will not be understood by an SMTP server (or FTP, or other server ...


3

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).


3

Because there's nothing listening there. If you'd expect an X server to answer, you'll need to tell it to enable TCP (remove the -nolisten tcp for instance). But if you don't need your X server to be accessed directly over the network (other than tunnelled/proxied over ssh), it's probably wiser to leave it there. You can connect to your X server with a ...


3

ssh user@server telnet localhost 1234


3

You are trying to test connectivity to a remote Web server with telnet? Then, no: you do not need telnet servers. The remote HTTP server is waiting for commands, as indicated by the escape character. When it times out waiting, the connection is closed. So... telnet <hostname or ip address> 80 Then type some HTTP commands: GET / HTTP/1.1 host: ...


2

My working case with a small correction: nohup openvpn /etc/init.d/ovpn/Userxxx.ovpn & /etc/init.d/ovpn/telnet_commands.sh


2

I finally found an answer in Anne Baretta's Linux Keyboard Hall of Shame... it seems that changing key mappings in xterm / rxvt does no good for telnet. I validated this when I sniffed the telnet connection. First I sniffed the telnet session and saw that Backspace sent 0x7f to the host. Next I intentionally broke Backspace in rxvt using stty erase $ (thus ...


2

There is Jabber Telnet Bot that is bot that provides jabber to telnet gateway. Project is little old, and I was unable to run in successfully, but there is a chance that it will run on another configurations. After downloading package you need to modify configuration in cfg/jbtelbot.conf file to set host where you want to connect and Jabber account on which ...


2

Have you tried turning off localchars in your telnet client? bash$ telnet telnet> toggle localchars Won't recognize certain control characters. telnet> open myhost You may also be able to put this command in the ~/.telnetrc file, depending on your version of telnet.


2

You might try the 8-bit clean mode... it stops telnet from interpreting much of the data telnet -8 host port (This is a shot in the dark) For the most part, you're on the right track, trying to get telnet to stop pre-interpreting keystrokes... such as the CTRL-C and CTRL-Z and others. 8bit mode should help.



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