CentOS 7 with MailScanner failed to use Sophos SAVI

CentOS 7 with MailScanner failed to use Sophos SAVI.

My MailScanner doesn't work with SAVI mode (use less CPU resource), just work with Sophos mode (user more CPU resource).

I have complied the SAVI-Perl-0.30 and the after "make" the SAVI.so has been deployed to /usr/local/lib64/perl5/auto/SAVI/SAVI.so.

I set "Virus Scanners = sophossavi" in MailScanner.conf, let it make use SAVI module.
However I got the following error in maillog, keep saying "SAVI Perl module not found"

Apr 20 15:07:56 myserver MailScanner[5266]: MailScanner E-Mail Virus Scanner version 4.85.2 starting...
Apr 20 15:07:56 myserver MailScanner[5266]: Reading configuration file /etc/MailScanner/MailScanner.conf
Apr 20 15:07:56 myserver MailScanner[5266]: Reading configuration file /etc/MailScanner/conf.d/README
Apr 20 15:07:56 myserver MailScanner[5266]: Using SpamAssassin results cache
Apr 20 15:07:56 myserver MailScanner[5266]: Connected to SpamAssassin cache database
Apr 20 15:07:56 myserver MailScanner[5266]: Enabling SpamAssassin auto-whitelist functionality...
Apr 20 15:07:58 myserver MailScanner[5266]: SAVI Perl module not found, did you install it?

If I set  "Virus Scanners = sophos" in MailScanner.conf, it works, but use a lot of CPU and performance is not good.

In the MailScanner.conf, seems no conf to tell the MailScanner where is the SAVI.so file.

Software:
CentOS 7.3 x64
sendmail 8.14 (build-in)
MailScanner 4.85.2
Sophos Antivirus for Linux 9.12.3
SAVI-Perl-0.30

Sophos related settings in MailScanner.conf
Virus Scanners = sophossavi
Sophos IDE Dir = /opt/sophos-av/lib/sav
Sophos Lib Dir = /opt/sophos-av/lib64
Monitors For Sophos Updates = /opt/sophos-av/lib/sav/*.ide

Solution:
It is because the service startup script don't have library path.

Edit /etc/sysconfig/MailScanner and add the following line will fix the issue.
export LD_LIBRARY_PATH=/opt/sophos-av/lib64

CentOS/RHEL 7 Mailscanner + sendmail, prevent systemd stop sendmail with stopms option

In CentOS 6 and previous versions, running "/etc/init.d/MailScanner stopms" will terminate MailScanner processes only, without stopping the sendmail processes.

However on CentOS 7, init was replaced by systemd. systemd would treat the MailScanner and sendmail process at one service, if you stopms or kill MailScanner, systemd will run "/etc/init.d/MailScanner stop" to stop the sendmail processes too.

Make the following changes to overcome this issue:
# mkdir /etc/systemd/system/MailScanner.service.d
create custom_script.conf with followings:
[Service]
RemainAfterExit=yes

# systemctl daemon-reload


Reference:
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/System_Administrators_Guide/sect-Managing_Services_with_systemd-Unit_Files.html#brid-Managing_Services_with_systemd-Overriding_Unit_Mod
http://www.unix.com/man-page/centos/5/systemd.service/

RemainAfterExit=
  Takes a boolean value that specifies whether the service shall be considered active even when all its processes exited. Defaults to no.