The RHEL 7.5 release brings the following main enhancements:
- Security & compliance
- Red Hat Ansible is now integrated with OpenSCAP, generating playbooks directly from scans.
- The SAMBA suite defaults to the SMB protocol version 3.
- Network-Bound Disk Encryption (NBDE) has been improved and now supports automatic decryption of data volumes (see here).
- Performance & efficiency
- Virtual Data Optimizer (VDO) provides storage optimizations (see here, here, here, here and here) through data de-duplication and compression capabilities.
- Distributed File System (DFS) is now supported in the SMB protocol versions 2 and 3, allowing multiple SMB file systems to be seen as a single, virtual system.
- Identity Management and Access Control
- Windows Server 2016 forest is now supported for a cross-forest trust with Identity Management and integration with Active Directory has been enhanced.
- The OpenLDAP suite now uses the OpenSSL library instead of the NSS library.
- SSSD performance has been improved with several missing indexes added.
- The tcpdump utility now supports the virtio-vsock communication device, allowing tcpdump to filter and analyze virtio communication between a hypervisor and a guest virtual machine.
- The DNS3 option is now supported in ifcfg-* files.
- It is now possible to configure NetworkManager to never stop trying to get or renew a lease from a DHCP server until it is successful.
- Changes to the /etc/resolv.conf file are now automatically recognized and applied to running programs.
Although the kernel version is still 3.10 for most of the architectures, 64-bit ARM, IBM POWER9 (little endian) and IBM z Systems get version 4.14 through the kernel-alt packages.
The RHEL 7.5 release deprecates the use of Python 2.
The use of ZONE in the ifcfg-* files no longer works (source).
In addition, an official technical overview is available here.
Also, Joe Brockmeier from RedHat wrote an article about Container-related Changes in Red Hat Enterprise Linux 7.5.