Oracle Linux 7.4 发布了。改版本的更新领域主要涉及安全性的改进，以及对云和容器环境的支持的改进。
Oracle Linux 7.4 通过几项新功能不断提升安全性，包括：
UEFI Secure Boot
A system in Secure Boot mode loads only those boot loaders and kernels that have been signed by Oracle. Oracle has updated the kernel and grub2 packages to sign them with a valid Extended Validation (EV) certificate. The EV certificate has been compiled into the shim binary and has been signed by Microsoft.
openSSH 现在使用 SHA-2
By default, the algorithm for public key signatures that is used in this release is SHA-2. SHA-1 is available for backward compatibility purposes only.
Yum 添加新的 payload_gpgcheck 选项
Enhances security during installation. The new payload_gpgcheck option enables yum to perform a GNU Privacy Guard (GPG) signature check on the payload sections of packages. This capability provides enhanced security and integrity when installing packages.
NBDE enables you to encrypt root volumes of hard drives on physical machines without requiring you to manually enter a password when the systems are rebooted.
新的 usbguard 包
The USBGuard software framework provides system protection against intrusive USB devices by implementing basic whitelisting and blacklisting capabilities that are based on device attributes.
Oracle Linux 7.4 不断加强客户的云和容器部署：
Btrfs is the ideal filesystem for supporting containers in the cloud. We continue to support and enhance Btrfs in Oracle Linux 7 with Unbreakable Enterprise Kernel Release 4 allowing you to continue to use Btrfs for your container cloud deployments.
Prevents container users from being able to gain the same privileges at the global level by allowing separation of the container namespace from the underlying operating system namespace.
Oracle Linux 7 Update 4 makes it even easier to install and add a system to Spacewalk by not requiring the spacewalk client to be installed before registering with the Spacewalk server.
Replaced ticket spin locks with queued spin locks which provide better scalability under contention and higher performance overall.
新增 http-parser 性能安装包
http-parser is designed for high performance web applications by eliminating buffering, system calls and allowing interrupts.
新增 libfastjson 安装包
libfastjson is a limited feature set JSON library that provides significantly improved performance, compared to json-c.