==== Required information ====
- iRedMail version (check /etc/iredmail-release): 0.9,6
- Linux/BSD distribution name and version: CentOs7
- Store mail accounts in which backend (LDAP/MySQL/PGSQL):  MySQL
- Web server (Apache or Nginx): Apache
- Manage mail accounts with iRedAdmin-Pro? No
- Related log if you're reporting an issue:
====

No mail is being sent or received since upgrade. Any solutions to this or pointers.. Many Thanks

From the Outside email clients cannot connect.

Feb 28 11:49:10 iredmail postfix/submission/smtpd[4551]: warning: hostname iredmail.eurogroup-ms.net does not resolve to address 81.150.28.114
Feb 28 11:49:10 iredmail postfix/submission/smtpd[4551]: connect from unknown[81.150.28.114]
Feb 28 11:49:10 iredmail postfix/submission/smtpd[4551]: SSL_accept error from unknown[81.150.28.114]: lost connection
Feb 28 11:49:10 iredmail postfix/submission/smtpd[4551]: lost connection after STARTTLS from unknown[81.150.28.114]
Feb 28 11:49:10 iredmail postfix/submission/smtpd[4551]: disconnect from unknown[81.150.28.114]
Feb 28 11:49:10 iredmail postfix/submission/smtpd[4551]: warning: hostname iredmail.eurogroup-ms.net does not resolve to address 81.150.28.114
Feb 28 11:49:10 iredmail postfix/submission/smtpd[4551]: connect from unknown[81.150.28.114]
Feb 28 11:49:10 iredmail postfix/submission/smtpd[4551]: SSL_accept error from unknown[81.150.28.114]: lost connection
Feb 28 11:49:10 iredmail postfix/submission/smtpd[4551]: lost connection after STARTTLS from unknown[81.150.28.114]
Feb 28 11:49:10 iredmail postfix/submission/smtpd[4551]: disconnect from unknown[81.150.28.114]

FCrDNS test result:
81.150.28.114 resolved to iredmail.eurogroup-ms.net.
iredmail.eurogroup-ms.net resolved to 81.150.28.114;
rDNS if forward confirmed.

From the inside Mail cannot be sent

SMTP Error (451): Failed to add recipient "r.warner@domain.com" (4.3.0 <r.warner@domains.com>: Temporary lookup failure).

Feb 28 11:49:37 iredmail postfix/submission/smtpd[4555]: connect from iredmail.eurogroup-ms.net[127.0.0.1]
Feb 28 11:49:37 iredmail postfix/proxymap[4552]: error: open /etc/postfix/mysql/sender_dependent_relayhost_maps.cf: No such file or directory
Feb 28 11:49:38 iredmail postfix/proxymap[4552]: warning: mysql:/etc/postfix/mysql/sender_dependent_relayhost_maps.cf is unavailable. open /etc/postfix/mysql/sender_dependent_relayhost_maps.cf: No such file or directory
Feb 28 11:49:38 iredmail postfix/trivial-rewrite[4598]: warning: proxy:mysql:/etc/postfix/mysql/sender_dependent_relayhost_maps.cf lookup error for "<>"
Feb 28 11:49:38 iredmail postfix/trivial-rewrite[4598]: warning: sender_dependent_relayhost_maps lookup failure
Feb 28 11:49:38 iredmail postfix/submission/smtpd[4555]: NOQUEUE: reject: RCPT from iredmail.eurogroup-ms.net[127.0.0.1]: 451 4.3.0 <r.warner@eurogroup-ms.com>: Temporary lookup failure; from=<welcome@eafs-info.com> to=<r.warner@eurogroup-ms.com> proto=ESMTP helo=<iredmail.eurogroup-ms.net>
Feb 28 11:49:38 iredmail roundcube: ERROR: Invalid response code received from server (451)
Feb 28 11:49:38 iredmail roundcube: <3bo7m2a2> SMTP Error: Failed to add recipient 'r.warner@eurogroup-ms.com'. 4.3.0 <r.warner@eurogroup-ms.com>: Temporary lookup failure (Code: 451) in /var/www/roundcubemail-1.1.4/program/lib/Roundcube/rcube.php on line 1648 (POST /mail/?_task=mail&_unlock=loading1488282576406&_lang=en_US&_framed=1&_action=send)
Feb 28 11:49:38 iredmail postfix/submission/smtpd[4555]: disconnect from iredmail.eurogroup-ms.net[127.0.0.1]
Feb 28 11:52:31 iredmail postfix/anvil[4554]: statistics: max connection rate 2/60s for (submission:81.150.28.114) at Feb 28 11:49:10
Feb 28 11:52:31 iredmail postfix/anvil[4554]: statistics: max connection count 1 for (submission:81.150.28.114) at Feb 28 11:49:10
Feb 28 11:52:31 iredmail postfix/anvil[4554]: statistics: max cache size 1 at Feb 28 11:49:10
Feb 28 11:53:53 iredmail clamd[1415]: SelfCheck: Database status OK.