======== Required information ====
- iRedMail version (check /etc/iredmail-release): 0.9.8 MYSQL edition.
- Linux/BSD distribution name and version: ubuntu 16.04
- 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.
====

After install iredmail, it work great. imap and smtp all work with STARTTLS . port 143,993 and port 587 tested.
after I disabled ClamAV following the documents still work without problem.

but today when I using the mail client , I can't send mail anymore. I didn't change any settings after then , only reboot the server one time.
now imap work normaly , smtp can't connect, mail client shows connect timeout. And send mail using roundcube still work.
also, I try enable 465 SMTPS still cant connect
i attached my config file but I think I didn't modify it

=======================================================================
port check:

root@mail:~# lsof -i:587
COMMAND   PID USER   FD   TYPE    DEVICE SIZE/OFF NODE NAME
master  22174 root  115u  IPv4 805578885      0t0  TCP *:submission (LISTEN)
master  22174 root  116u  IPv6 805578886      0t0  TCP *:submission (LISTEN)

=======================================================================
iptable setting:

# Allow PING from remote hosts.
-A INPUT -p icmp --icmp-type echo-request -j ACCEPT

# ssh
-A INPUT -p tcp --dport 22 -j ACCEPT

# http, https
-A INPUT -p tcp --dport 80 -j ACCEPT
-A INPUT -p tcp --dport 443 -j ACCEPT

# smtp, submission
-A INPUT -p tcp --dport 25 -j ACCEPT
-A INPUT -p tcp --dport 587 -j ACCEPT

# pop3, pop3s
-A INPUT -p tcp --dport 110 -j ACCEPT
-A INPUT -p tcp --dport 995 -j ACCEPT
#-A INPUT -p tcp --dport 10110 -j ACCEPT

# imap, imaps
-A INPUT -p tcp --dport 143 -j ACCEPT
-A INPUT -p tcp --dport 993 -j ACCEPT
#-A INPUT -p tcp --dport 10143 -j ACCEPT

# lmtp
#-A INPUT -p tcp --dport 24 -j ACCEPT
#-A INPUT -p tcp --dport 1024 -j ACCEPT

# managesieve
#-A INPUT -p tcp --dport 4190 -j ACCEPT
#-A INPUT -p tcp --dport 10419 -j ACCEPT

# Dovecot SASL AUTH service for HAProxy
#-A INPUT -p tcp --dport 12346 -j ACCEPT

# ldap/ldaps
#-A INPUT -p tcp --dport 389 -j ACCEPT
#-A INPUT -p tcp --dport 636 -j ACCEPT
=======================================================================

● postfix.service - LSB: Postfix Mail Transport Agent
   Loaded: loaded (/etc/init.d/postfix; bad; vendor preset: enabled)
  Drop-In: /run/systemd/generator/postfix.service.d
           └─50-postfix-$mail-transport-agent.conf
   Active: active (running) since Tue 2018-05-08 23:16:59 EDT; 1min 16s ago
     Docs: man:systemd-sysv-generator(8)
  Process: 11194 ExecStop=/etc/init.d/postfix stop (code=exited, status=0/SUCCESS)
  Process: 11223 ExecStart=/etc/init.d/postfix start (code=exited, status=0/SUCCESS)
   CGroup: /system.slice/postfix.service
           ├─12044 /usr/lib/postfix/sbin/master
           ├─12045 pickup -l -t unix -u
           ├─12046 qmgr -l -t unix -u
           ├─12047 proxymap -t unix -u
           └─12049 showq -t unix -u

May 08 23:16:56 mail systemd[1]: Starting LSB: Postfix Mail Transport Agent...
May 08 23:16:56 mail postfix[11223]:  * Starting Postfix Mail Transport Agent postfix
May 08 23:16:59 mail postfix[11223]:    ...done.
May 08 23:16:59 mail systemd[1]: Started LSB: Postfix Mail Transport Agent.
May 08 23:16:59 mail postfix/master[12044]: daemon started -- version 3.1.0, configuration /etc/postfix