Using external SMTP on VPS?

Question

Mail server

Guys, please help me solve the problem with sending emails from the VPS server. In general, the built-in mail() function works properly. SMTP on the server is working properly (I receive / send letters successfully with the mail client), but when it comes to php, which needs to establish a connection with an external smtp (gmail, mail, yandex .. whatever) it doesn’t work. It seems that access to external smtp is closed for php. I do not know in which direction to dig, there is not enough knowledge. Maybe someone faced such a problem?

Answer 1

it may be closed,
check - from the console on the VPS, execute telnet 25 smtp.external.com (and other ports)
, of course, before that, connect from home, i.e. then that port is definitely open the
second problem is unresolvable names, unlikely, but still
check - pint -t smtp.external.com

Answer 2

Go through the encrypted smtp port (465).