postfix找不到libmysqlclient.so.18

　　最近需要下服务器上安装gitlab，在使用yum安装postfix之后，启动post报错，进行debug显示如下错误提示

[root@localhost ~]# systemctl status postfix.service
● postfix.service - Postfix Mail Transport Agent
   Loaded: loaded (/usr/lib/systemd/system/postfix.service; enabled; vendor preset: disabled)
   Active: failed (Result: exit-code) since 五 2018-03-02 09:43:51 CST; 27min ago
  Process: 11414 ExecStart=/usr/sbin/postfix start (code=exited, status=127)
  Process: 11411 ExecStartPre=/usr/libexec/postfix/chroot-update (code=exited, status=0/SUCCESS)
  Process: 11408 ExecStartPre=/usr/libexec/postfix/aliasesdb (code=exited, status=127)

3月 02 09:43:51 localhost.localdomain systemd[1]: Starting Postfix Mail Transport Agent...
3月 02 09:43:51 localhost.localdomain aliasesdb[11408]: /usr/sbin/postconf: error while loading shared libraries: libmysqlclient.so.18: cannot op...rectory
3月 02 09:43:51 localhost.localdomain aliasesdb[11408]: /usr/bin/newaliases: error while loading shared libraries: libmysqlclient.so.18: cannot o...rectory
3月 02 09:43:51 localhost.localdomain postfix[11414]: /usr/sbin/postfix: error while loading shared libraries: libmysqlclient.so.18: cannot open...irectory
3月 02 09:43:51 localhost.localdomain systemd[1]: postfix.service: control process exited, code=exited status=127
3月 02 09:43:51 localhost.localdomain systemd[1]: Failed to start Postfix Mail Transport Agent.
3月 02 09:43:51 localhost.localdomain systemd[1]: Unit postfix.service entered failed state.
3月 02 09:43:51 localhost.localdomain systemd[1]: postfix.service failed.

　　错误显示的是libmysqlclient.so.18没有找到。

　　在google解决方法之后，找到的解决方法

　　　　在mysql的安装路径下找到libmysqlclient.so.18，再使用软连接 到/usr/lib路径下。

　　在完成添加之后启动还是会显示上面的错误，最终把postfix卸载掉 重新yum 安装才正常启动