用老师提供的命令
rpm -Uvh http://www.percona.com/downloads/percona-release/redhat/0.1-4/percona-release-0.1-4.noarch.rpm

yum install Percona-XtraDB-Cluster-57 -y

但是好像不成功啊，日志如下(VM虚拟机上安装的)

Total size: 62 M
Downloading packages:
warning: /var/cache/yum/x86_64/7/percona-release-x86_64/packages/Percona-XtraDB-Cluster-server-57-5.7.30-31.43.1.el7.x86_64.rpm: Header V4 RSA/SHA256 Signature, key ID 8507efa5: NOKEY
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-Percona

The GPG keys listed for the “Percona-Release YUM repository - x86_64” repository are already installed but they are not correct for this package.
Check that the correct key URLs are configured for this repository.

Failing package is: Percona-XtraDB-Cluster-server-57-5.7.30-31.43.1.el7.x86_64
GPG Keys are configured as: file:///etc/pki/rpm-gpg/RPM-GPG-KEY-Percona