Using Linux or OSx, do what Sorin recommended but use port 465 instead. 25 is the generic SMTP port, but not what GMail uses. Also, I don’t believe you want to use -starttls smtp openssl s_client -connect smtp.gmail.com:465 You should get lots of information on the SSL session and the response: 220 mx.google.com … Type … Read more
I’ve used various methods for scripting telnet sessions under Unix, but the simplest one is probably a sequence of echo and sleep commands, with their output piped into telnet. Piping the output into another command is also a possibility. Silly example (echo password; echo “show ip route”; sleep 1; echo “quit” ) | telnet myrouter … Read more
The client cannot specify the timeout, it is the server configuration that determines the maximum timeout value. The extra Keep-Alive header can inform the client how long the server is willing to keep the connection open (timeout=N value) and how many requests you can do over the same connection (max=M) before the server will force … Read more
Best C# Telnet Lib I’ve found is called Minimalistic Telnet. Very easy to understand, use and modify. It works great for the Cisco routers I need to configure.
You can’t, because as soon as you start using TLS, the conversation becomes encrypted, and you probably don’t speak that language 😉 Here is what you can do instead: openssl s_client -debug -starttls smtp -crlf -connect localhost:25 OpenSSL will do the STARTTLS handshake for you and you will be able to pick up the conversation … Read more
While I’d suggest using expect, too, for non-interactive use the normal shell commands might suffice. telnet accepts its command on stdin, so you just need to pipe or write the commands into it through heredoc: telnet 10.1.1.1 <<EOF remotecommand 1 remotecommand 2 EOF (Edit: Judging from the comments, the remote command needs some time to … Read more
You could do telnet stackoverflow.com 80 And then paste GET /questions HTTP/1.0 Host: stackoverflow.com # add the 2 empty lines above but not this one Here is a transcript $ telnet stackoverflow.com 80 Trying 151.101.65.69… Connected to stackoverflow.com. Escape character is ‘^]’. GET /questions HTTP/1.0 Host: stackoverflow.com HTTP/1.1 200 OK Content-Type: text/html; charset=utf-8 …
In Windows, an executable is either a console application or a Windows application (or a SFU or Native application, but that doesn’t matter here). The kernel checks a flag in the executable to determine which. When starting using CreateProcess WinAPI function, if it is a console application, the kernel will create a console window for … Read more
The RHEL/CentOS 5.4 telnet client is installed at /usr/kerberos/bin/telnet. Your $PATH variable thus needs /usr/kerberos/bin listed. (Preferably before /usr/bin) If for some reason you don’t have that file installed, it’s part of the package krb5-workstation. Installing that package manually or via YUM should give you what you need. You can check quick with which telnet … Read more
Nope. Either you’re walking them through installing the telnet client native to Windows, or you’re having them install Putty or a similar app. The functionality was deemed a security risk and so was turned off.