1. Release Notes for Unbreakable Enterprise Kernel Release 4 Update 2
  2. New Features and Changes
  3. Technology Preview

Technology Preview

The following features included in the Unbreakable Enterprise Kernel Release 4 are still under development, but are made available for testing and evaluation purposes.

  • Ceph File System

    The Ceph File System (CephFS) feature of Ceph is in technology preview.

  • DCTCP (Data Center TCP)

    DCTCP enhances congestion control by making use of the Explicit Congestion Notification (ECN) feature of state-of-the-art network switches. DCTCP reduces buffer occupancy and improves throughput by allowing a system to react more intelligently to congestion than is possible using TCP.

  • DRBD (Distributed Replicated Block Device)

    A shared-nothing, synchronously replicated block device (RAID1 over network), designed to serve as a building block for high availability (HA) clusters. It requires a cluster manager (for example, pacemaker) for automatic failover.

  • Kernel module signing facility

    Applies cryptographic signature checking to modules on module load, checking the signature against a ring of public keys compiled into the kernel. GPG is used to do the cryptographic work and determines the format of the signature and key data.

  • NFS over RDMA interoperation with ZFS and Oracle Solaris

    NFS over RDMA does not yet fully interoperate with ZFS and Oracle Solaris. NFS over RDMA for NFS versions 3 and 4 is supported for Oracle Linux systems using the Oracle InfiniBand stack and is more efficient than using NFS with TCP over IPoIB. Currently, only the Mellanox ConnectX-2 and ConnectX-3 Host Channel Adapters (HCAs) pass the full Connectathon NFS test suite and are supported.

  • NFS server-side copy offload

    NFS server-side copy offload is an NFS v4.2 feature that reduces the overhead on network and client resources by offloading copy operations to one or more NFS servers rather than involving the client in copying file data over the network.

  • Server-side parallel NFS

    Server-side parallel NFS (pNFS) improves the scalability and performance of an NFS server by making file metadata and data available on separate paths.