==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release):  1.7.1 MARIADB edition.
- Deployed with iRedMail Easy or the downloadable installer? NO
- Linux/BSD distribution name and version: 13.4-RELEASE-p1 FreeBSD not newsyslog work
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): Mysql
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? no
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

cat /etc/newsyslog.conf
last line
<include> /usr/local/etc/newsyslog.conf.d/[!.]*.conf

not work

ls -l /usr/local/etc/newsyslog.conf.d/
total 16
-rw-r--r--  1 root  wheel  295 Dec  9 10:25 dovecot
-rw-r--r--  1 root  wheel   94 Dec  9 10:25 iredapd
-rw-r--r--  1 root  wheel  114 Dec  9 10:25 mlmmjadmin
-rw-r--r--  1 root  wheel  183 Dec  9 10:25 php-fpm

Thereis no *.conf

and

newsyslog -nv

not show /usr/local/etc/newsyslog.conf.d/

and need change line in file /etc/newsyslog.conf to

<include> /usr/local/etc/newsyslog.conf.d/[!.]*

and work fine.

to test
newsyslog -nv