##提示如下
** Found 2 pre-existing rpmdb problem(s), ‘yum check’ output follows:
2:postfix-2.10.1-7.el7.x86_64 has missing requires of libmysqlclient.so.18()(64bit)
2:postfix-2.10.1-7.el7.x86_64 has missing requires of libmysqlclient.so.18(libmysqlclient_18)(64bit)
##解决方法
安装Percona-XtraDB-Cluster-shared-55-5.5.37-25.10.756.el6.x86_64.rpm这个包即可
1.wget http://www.percona.com/redir/downloads/Percona-XtraDB-Cluster/5.5.37-25.10/RPM/rhel6/x86_64/Percona-XtraDB-Cluster-shared-55-5.5.37-25.10.756.el6.x86_64.rpm
2.rpm -ivh Percona-XtraDB-Cluster-shared-55-5.5.37-25.10.756.el6.x86_64.rpm
yum localinstall mysql80-community-release-el8-4.noarch.rpm
yum localinstall mysql80-community-release-el7-11.noarch.rpm