Why doesn't the server want to send emails with the mail() function?

Question

PHP

Installed Vesta (fresh) on CentOS 7.3.1611 x64
, moreover, I have a certain php file running in cron and there are some errors and such letters (in the spam folder) arrive on my soap registered in Vesta with the title:
(Cron Daemon) <[email protected]>
and text:
PHP Notice: Undefined index: SERVER_PROTOCOL in /home/admin/web/my-domen.ru/public_html/file.php on line 21
PHP Notice: Undefined index: SERVER_PROTOCOL in /home/admin/web/my-domen.ru/public_html /file.phpp on line 21
PHP Notice: Undefined index: SERVER_PORT in /home/admin/web/my-domen.ru/public_html/file.php on line 22
PHP Notice: Undefined index: SERVER_PORT in /home/admin/web /my-domain.ru/public_html/file.php on line 22
PHP Notice: Undefined index: SERVER_NAME in /home/admin/web/my-domen.ru/public_html/file.php on line 24
PHP Notice: Undefined index: REQUEST_URI in /home/admin/web/my-domen.ru/ public_html/file.php on line 24
ps aux | grep sendmail
root 10324 0.0 0.1 112648 968 pts/0 R+ 03:59 0:00 grep --color=auto sendmail
After executing the mail() function on the server, empty files are created in the var/log/ folder:
messages-20170903
maillog-20170903
Karoch I tested with another soap. I sent it to mail.ru and it ended up in the spam folder, but it came. And gmail.com doesn't even come to the spam folder! Such nonsense, I don’t know, can I somehow fix this in the gmail settings? I doubt it, of course.
Karoch I removed from some letters(Cron Daemon) <[email protected]>
the spam label and started my letters at least coming to spam.
Is there any way to remove the notification about these php errors? Preferably this particular php file?

Answer 1

After executing the mail() function on the server, empty files are created in the var/log/ folder:

- that's how it should be. the fact that empty means you are not sending anything, most likely, you need to flatter the code.
-it would not be bad to attach a piece of code, maybe there is some kind of error (but as an option, you can debug it)
And just so that it would not fly into spam, I would configure dkim / spf / dmarc
---- I would do that. This is purely my opinion.