3. Technology Previews

Open Multicast Ping (Omping) is a tool to test the IP multicast functionality primarily in the local network. This utility allows users to test multicast and assists in the diagnosing if an issues is in the network configuration or elsewhere (i.e. a bug). In Red Hat Enterprise Linux 6 omping is provided as a Technology Preview.

Matahari provides a set of Application Programming Interfaces (APIs) for operating systems management for remote access over QMF/QPID. In Red Hat Enterprise Linux 6.1, Matahari is considered a Technology Preview feature.

The System Information Gatherer and Reporter (SIGAR) is a library and command-line tool for accessing operating system and hardware level information across multiple platforms and programming languages. In Red Hat Enterprise Linux 6.1, SIGAR is considered a Technology Preview package.

Red Hat Enterprise Linux 6 includes fsfreeze as a Technology Preview. fsfreeze is a new command that halts access to a filesystem on disk. fsfreeze is designed to be used with hardware RAID devices, assisting in the creation of volume snapshots. Further details on fsfreeze are in the fsfreeze(8) man page.

DIF/DIX, is a new addition to the SCSI Standard and a Technology Preview in Red Hat Enterprise Linux 6. DIF/DIX increases the size of the commonly used 512-byte disk block from 512 to 520 bytes, adding the Data Integrity Field (DIF). The DIF stores a checksum value for the data block that is calculated by the Host Bus Adapter (HBA) when a write occurs. The storage device then confirms the checksum on receive, and stores both the data and the checksum. Conversely, when a read occurs, the checksum can be checked by the storage device, and by the receiving HBA.

The DIF/DIX hardware checksum feature must only be used with applications that exclusively issue O_DIRECT I/O. These applications may use the raw block device, or the XFS file system in O_DIRECT mode. (XFS is the only filesystem that does not fall back to buffered IO when doing certain allocation operations.) Only applications designed for use with O_DIRECT I/O and DIF/DIX hardware should enable this feature. Red Hat Enterprise Linux 6 includes the Emulex LPFC driver version 8.3.5.17, introducing support for DIF/DIX. For more information, refer to the Storage Administration Guide

Filesystem in Userspace (FUSE) allows for custom filesystems to be developed and run in user-space.

Btrfs is under development as a file system capable of addressing and managing more files, larger files, and larger volumes than the ext2, ext3, and ext4 file systems. Btrfs is designed to make the file system tolerant of errors, and to facilitate the detection and repair of errors when they occur. It uses checksums to ensure the validity of data and metadata, and maintains snapshots of the file system that can be used for backup or repair. The btrfs Technology Preview is only available on the x86_64 architecture.

Red Hat Enterprise Linux 6 features the new LVM application programming interface (API) as a Technology Preview. This API is used to query and control certain aspects of LVM.

FS-Cache is a new feature in Red Hat Enterprise Linux 6 that enables networked file systems (e.g. NFS) to have a persistent cache of data on the client machine.

eCryptfs is a stacked, cryptographic file system. It is transparent to the underlying file system and provides per-file granularity. eCryptfs is provided as a Technology Preview in Red Hat Enterprise Linux 6.

The IPv6 support in IPVS (IP Virtual server) is considered Technology Preview.

Pacemaker, a scalable high-availability cluster resource manager, is included in Red Hat Enterprise Linux 6 as a Technology Preview. Pacemaker is not fully integrated with the Red Hat cluster stack.

XFS filesystem failover in the Red Hat Enterprise Linux 6 High Availability Add-On is considered a Technology Preview. Note: XFS and the Scalable File System Add-On are fully-supported in Red Hat Enterprise Linux 6.

Cluster membership can now be initiated using udp-unicast (UDPU). The older protocol (multicast) is often restricted by corporate IT policy, making it difficult to deploy clusters. Introducing UDPU support alliviates that limitation. This feature is considered a Technology Preview in Red Hat Enterprise Linux 6.1.

The certmonger service aims to manage certificates on behalf of services running on client systems. It warns administrators when a certificate which it has been asked to watch is nearing the end of its validity period, and can be told to attempt to automatically obtain a new certificate when this happens. It supports certificates and private keys stored in either PEM or NSS database formats. It can interact with CAs running either IPA or certmaster, and is intended to be extensible to support other implementations.

TPM hardware can create, store and use RSA keys securely (without ever being exposed in memory), verify a platform's software state using cryptographic hashes and more. The user space libraries, trousers and tpm-tools are considered a Technology Preview in this Red Hat Enterprise Linux 6.

The Brocade BFA driver is considered a Technology Preview feature in Red Hat Enterprise Linux 6. The BFA driver supports Brocade FibreChannel and FCoE mass storage adapters.

The SR-IOV functionality of the Emulex be2net driver is considered a Technology Preview in Red Hat Enterprise Linux 6.

The audit package contains the user space utilities for storing and searching the audit records generated by the audit subsystem in the Linux 2.6 kernel. Within the audispd-plugins subpackage is a utility that allows for the transmission of audit events to a remote aggregating machine. This remote audit logging application, audisp-remote, is considered a Technology Preview in Red Hat Enterprise Linux 6.

Linux (NameSpace) Containers [LXC] is a Technology Preview feature in Red Hat Enterprise Linux 6 that provides isolation of resources assigned to one or more processes. A process is assigned a separate user permission, networking, filesystem name space from its parent.

A diagnostic pulse can now be issued on the IPMI interface using the fence_ipmilan agent. This new Technology Preview is used to force a kernel dump of a host if the host is configured to do so. Note that this feature is not a substitute for the 'off' operation in a production cluster.