Wordpress only can send few emails before postfix failure in Centos 6.5
Hi, I've configured a Centos 6.5 droplet with postfix and I've installed a Wordpress page and it's running without issue but emails. When I send 1 or 2 emails through a conact form in WP (Contact Form 7 plugin) postfix seems to fail becouse I need to restart postfix service to send emails again. However sending emails with php mail function works fine, also in webmail, even when contact form in WP doesn't send anymore I can send email through these ways without any problem.
The problem seems to be in postfix sendmail becouse looks like only affect wordpress.
Maillog registers the few emails that I can send with wordpress before failure and when it happens maillog doesn't log a single line anymore, errors neither. After that if I send an email with php mail function for example, maillog register that email and it is received properly but always need to restart postfix to send email with WP again.
Can anyone help me with this?
Thanks in advance.