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
