6.1 Release Notes
Release Notes for Red Hat Enterprise Linux 6.1
Red Hat Engineering Content Services
1. Hardware Support
Traditionally, network interfaces in Linux are named
eth[X]. However, in many cases, these names do not correspond to actual labels on the chassis. Modern server platforms with multiple network adapters can encounter non-deterministic and counterintuitive naming of these network interfaces.
The implementation of version 3.0 of the Universal Serial Bus (USB 3.0) specification is a fully supported feature in Red Hat Enterprise Linux 6.1. USB 3.0 support was previously considered a Technology Preview in previous releases.
On Nehalem-EX, hot-adding of CPUs and memory is now fully supported in Red Hat Enterprise Linux 6.1. Note, however that the hardware must also support hot-adding. Damage may occur from an attempt to hot-add CPUs or memory on hardware without support for hot-adding.
Red Hat Enterprise Linux 6.1 features a wide range of driver updates, including updates to the following device drivers:
ixgbedriver for Intel 10 Gigabit PCI Express Network devices
mlx4driver for Mellanox ConnectX HCA InfiniBand hardware, providing support for Mellanox Connect X2/X3 10GB devices
be2netdriver for ServerEngines BladeEngine2 10Gbps network devices
bnx2driver for Broadcom NetXtreme II network devices, including support for Advanced Error Reporting (AER), and PPC support for 5709 devices
bnx2idriver for Broadcom NetXtreme II iSCSI
bnx2xdriver for Broadcom Everest network devices
ixgbevfVirtual Function drivers
tg3driver for Broadcom Tigon3 ethernet devices
bfadriver for Brocade Fibre Channel to PCIe Host Bus Adapters
bnadriver for Brocade 10G PCIe ethernet Controllers
cxgb4driver for Chelsio Terminator4 10G Unified Wire Network controllers
be2iscsidriver for ServerEngines BladeEngine 2 Open iSCSI devices
be2netdriver for ServerEngines BladeEngine2 10Gbps network devices
lpfcdriver for Emulex Fibre Channel HBAs
e1000edrivers for Intel PRO/1000 network devices
- Intel Iron Pond ethernet driver
- Intel Kelsey Peak Wireless driver
- Intel SCU driver
megaraid_sasdriver for LSI MegaRAID SAS controllers
- mpt2sas driver for the SAS-2 family of adapters from LSI Logic
Control groups are a feature of the Linux kernel introduced in Red Hat Enterprise Linux 6. Each control group is a set of tasks on a system that have been grouped together to better manage their interaction with system hardware. Control groups can be tracked to monitor the system resources that they use. Additionally, system administrators can use control group infrastructure to allow or to deny specific control groups access to system resources such as memory, CPUs (or groups of CPUs), networking, I/O, or the scheduler.
group_idle, provides better throughput with control groups while maintaining fairness.
Red Hat Enterprise Linux 6.1 introduces support for Receive Packet Steering (RPS) and Receive Flow Steering (RFS). Receive Packet Steering allows incoming network packets to be processed in parallel over multiple CPU cores. Receive Flow Steering chooses the optimal CPU to process network data intended for a specific application.
kdump is an advanced crash dumping mechanism. When enabled, the system is booted from the context of another kernel. This second kernel reserves a small amount of memory, and its only purpose is to capture the core dump image in case the system crashes.
The kernel in Red Hat Enterprise Linux 6.1 provides the following notable performance improvements:
- Updates and improvements to Transparent Huge Pages (THP) support
- Updates to perf_event, adding the new perf lock feature to better analyze lock events.
- kprobes jump optimization, reducing overhead and enhancing SystemTap performance.
- Updates to i7300_edac and i7core_edac, providing support for monitoring of memory errors on motherboards using Intel 7300 chipset
Red Hat Enterprise Linux 6.1 provides a range of updates for graphics hardware. The driver for Intel Generation 6 Graphics on the Sandy Bridge processor is introduced in this release, providing fully accelerated 2D and 3D graphics on these devices. Additionally, this release introduces support for the Matrox MGA-G200ER graphics chipset.
xorg-x11-drv-xgivideo driver to support the XGI Z9S AND Z11 chipsets. The SIS driver that provided support for older XGI hardware is no longer being updated to support new hardware.
NetworkManager is the desktop tool that is used to set up, configure and manage a wide range of network connection types. In Red Hat Enterprise Linux 6.1, NetworkManager has improved support for the configuration of Wi-Fi Protected Access (WPA) Enterprise and Internet Protocol version 6 (IPv6).
Red Hat Enterprise Linux 6.1 provides updated Advanced Linux Sound Architecture - High Definition Audio (ALSA-HDA) drivers.
The LVM snapshot feature provides the ability to create backup images of a logical volume at a particular instant without causing a service interruption. When a change is made to the original device (the origin) after a snapshot is taken, the snapshot feature makes a copy of the changed data area as it was prior to the change so that it can reconstruct the state of the device. In Red Hat Enterprise Linux 6.1 the ability to take a snapshot of a mirrored logical volume is a fully supported feature.
It is now possible to combine RAID0 (striping) and RAID1 (mirroring) in a single logical volume in LVM. Creating a logical volume while simultaneously specifying the number of mirrors ('--mirrors X') and the number of stripes ('--stripes Y') results in a mirror devices whose constituent devices are striped.
5. Authentication and Interoperability
The System Security Services Daemon (SSSD) implements a set of services for central management of identity and authentication. Centralizing identity and authentication services enables local caching of identities, allowing users to still identify in cases where the connection to the server is interrupted. SSSD supports many types of identity and authentication services, including: Red Hat Directory Server, OpenLDAP, 389, Kerberos and LDAP. SSSD in Red Hat Enterprise Linux 6.1 is updated to version 1.5, providing the following bug fixes and enhancements:
- Netgroups support
- Improved online/offline detection
- Improved LDAP access-control provider with support for shadow and authorizedService
- Improved caching and cleanup logic for different schemata
- Improved DNS based discovery
- Automatic Kerberos ticket renewal
- Enablement of the Kerberos FAST protocol
- Better handling of password expiration
Red Hat Enterprise Linux 6.1 features IPA as a Technology Preview. IPA is an integrated security information management solution which combines Red Hat Enterprise Linux, Red Hat Directory Server, MIT Kerberos, and NTP. It provides web browser and command-line interfaces, and its numerous administration tools allow an administrator to quickly install, set up, and administer one or more servers for centralized authentication and identity management.
Samba is an open source implementation of the Common Internet File System (CIFS) protocol. It allows the networking of Microsoft Windows, Linux, UNIX, and other operating systems together, enabling access to Windows-based file and printer shares. Samba in Red Hat Enterprise Linux 6.1 is updated to version 3.5.6.
FreeRADIUS is an Internet authentication daemon, which implements the RADIUS protocol, as defined in RFC 2865 (and others). It allows Network Access Servers (NAS boxes) to perform authentication for dial-up users. FreeRADIUS in Red Hat Enterprise Linux 6.1 is updated to version 2.1.10.
Kerberos is a networked authentication system which allows users and computers to authenticate to each other with the help of a trusted third party, the KDC. In Red Hat Enterprise Linux 6.1, Kerberos (supplied by the krb5 package) is updated to version 1.9.
OpenSCAP is a set of open source libraries that support the Security Content Automation Protocol (SCAP) standards from the National Institute of Standards and Technology (NIST). OpenSCAP supports the SCAP components:
- Common Vulnerabilities and Exposures (CVE)
- Common Platform Enumeration (CPE)
- Common Configuration Enumeration (CCE)
- Common Vulnerability Scoring System (CVSS)
- Open Vulnerability and Assessment Language (OVAL)
- Extensible Configuration Checklist Description Format (XCCDF)
The Simple Protocol for Independent Computing Environments (SPICE) is a remote display protocol designed for virtual environments. SPICE users can view a virtualized desktop or server from the local system or any system with network access to the server. Red Hat Enterprise Linux 6.1 introduces support for smartcard passthough via the SPICE protocol.
This hardware (or a combination thereof) is not supported by Red Hat. For more information on supported hardware, please refer to http://www.redhat.com/hardware.
Red Hat Enterprise Linux 6.1 features improved support for iSCSI adapters at installation and boot time, including the ability to separate login credentials for iSCSI storage during installation and support for offload iSCSI adapters (e.g. the Emulex Tiger Shark adapter).
8. Compiler and Tools
SystemTap is a tracing and probing tool that allows users to study and monitor the activities of the operating system (particularly, the kernel) in fine detail. It provides information similar to the output of tools like netstat, ps, top, and iostat; however, SystemTap is designed to provide more filtering and analysis options for collected information.
- Alpha version of remote host scripting with --remote USER@HOST
- Optimization of near zero cost for dormant user probe points
The GNU Project Debugger (normally referred to as GDB) debugs programs written in C, C++, and other languages by executing them in a controlled fashion, and then printing out their data. GDB in Red Hat Enterprise Linux 6.1 is updated to version 7.2, providing many bugfixes and enhancements, including enhancements to the python scripting features, and C++ debugging enhancements.
Red Hat Enterprise Linux 6.1 introduces the Performance Application Programming Interface (PAPI). PAPI is a specification of a cross-platform interfaces to hardware performance counters on modern microprocessors. These counters exist as a small set of registers that count events, which are occurrences of specific signals related to a processor's function. Monitoring these events has a variety of uses in application performance analysis and tuning.
OProfile is a system-wide profiler for Linux systems. The profiling runs transparently in the background and profile data can be collected at any time. In Red Hat Enterprise Linux 6.1, OProfile is updated to version 0.9.6-12, providing support for AMD family 12h/14h/15h processors and Intel Westmere specific events.
Valgrind is an instrumentation framework for building dynamic analysis tools that can be used to profile applications in detail. Valgrind tools are generally used to automatically detect many memory management and threading problems. The Valgrind suite also includes tools that allow you to build new profiling tools to suit your needs.
The GNU Compiler Collection (GCC) includes, among others, C, C++, and Java GNU compilers and related support libraries. Red Hat Enterprise Linux 6 features version 4.4 of GCC, which includes the following features and enhancements:
- IBM z196 new instruction support and optimizations
- IBM z10 prefetch instruction support and optimizations
The libdfp library is updated in Red Hat Enterprise Linux 6.1. libdfp is a decimal floating point math library, and is available as an alternative to the glibc math functions on Power and s390x architectures, and is available in the supplementary channels.
Eclipse is a powerful development environment that provides tools for each phase of the development process. It is integrated into a single, fully configurable user interface for ease of use, featuring a pluggable architecture which allows for extension in a variety of ways.
- All the major plugins are refreshed, including Valgrind and OProfile integration and the tools for working with C and C++
- The Mylyn task-focused framework is updated
- Enhanced resource filtering for workspace contents
- performance enhancements when working with C, C++ and Java code bases
New IcedTea Web Open Source Web Browser Plugin and Webstart implementation for OpenJDK.
- Allows browsers such as Firefox to load Java applets embedded in a web page
- Provides framework to launch JNLP (Java Network Launching Protocol) files
- Rgmanager now supports the concept of critical and non-critical resources
- System Administrators can now configure and run a cluster using command line tools. This feature provides an alternative to manually editing the cluster.conf configuration file or using the graphical configuration tool, Luci.
- Red Hat Enterprise Linux High Availability on Red Hat Enterprise Linux KVM hosts is fully supported
- Comprehensive SNMP Trap support from central cluster daemons and sub-parts
- Additional watchdog integration allows a node to reboot itself when it loses quorum
The new host kernel networking backend, vhost, is a fully supported feature in Red Hat Enterprise Linux 6.1. vhost provides superior throughput and latency over the userspace implementation.
The qcow2 image format now supports caching of metadata. Additionally, support is added for live snapshots using external qcow2 images.
ioeventfd is now available, providing faster notification of block I/O.
The KVM hypervisor in Red Hat Enterprise Linux 6 features Kernel SamePage Merging (KSM), allowing KVM guests to share identical memory pages. Page sharing reduces memory duplication, allowing a host with similar guest operating systems to run more efficiently.
PCI configuration space access is improved, enabling a broader set of PCI devices to be device-assigned to guest VMs.
In Red Hat Enterprise Linux 6.1, the Time Stamp Counter (TSC) synchronization can now be automatically detected on guest bootup or when a host CPU is hot-plugged. Additionally, the TSC synchronization frequency is adjusted after a live migration.
Additionally, the new
drive_del command allows libvirt to safely remove a block device from a guest.
- The maximum display resolution on qemu-kvm is now 2560x1600 pixels
- Red Hat Enterprise Linux 6.1 includes the ability to expose an emulated Intel HDA sound card to all guests. This update enables native sound support for many guests including the 64-bit version of Windows 7
- QEMU char device flow control is enabled
- Message Signaled Interrupts (MSI) implemented for the win-virtio-blk driver
- A new standard interface for selecting/prioritizing the boot devices of the guest
- Stability improvements for live migration
- QEMU userspace static tracing
- Virtual disk online dynamic resize feature
- Forbid pci hot unplug of critical devices such as gpu, pci bus controller, isa bus controller
Effective software and infrastructure management requires a mechanism to handle the software inventory — both the type of products and the number of systems that the software is installed on. In parallel with Red Hat Enterprise Linux 6.1, Red Hat is introducing a new subscription service which provides oversight for the software subscriptions for an organization and a more effective content delivery system.
12. General Updates
In Red Hat Enterprise Linux 6.1, multilib Python packages and packages dependent on them have been removed. This was because installing Python packages for multiple architectures on one system can cause various problems. For more information, refer to https://access.redhat.com/knowledge/solutions/68140.
Red Hat Enterprise Linux 6 introduced the new Automated Bug Reporting Tool (ABRT). ABRT logs details of software crashes on a local system, and provides interfaces (both graphical and command line based) to report issues to Red Hat support. In Red Hat Enterprise Linux 6.1, ABRT is updated to version 1.1.16. This update provides an enhanced graphical user interface (GUI) in addition to a range of other bugfixes and enhancements.
openCryptoki contains version 2.11 of the PKCS#11 API, implemented for IBM Cryptocards. openCryptoki is updated in Red Hat Enterprise Linux 6.1, providing many bugfixes and enhancements, including better overall performance.
OpenLDAP is an open source suite of Lightweight Directory Access Protocol (LDAP) applications and development tools. OpenLDAP in Red Hat Enterprise Linux 6.1 is updated to version 2.4.23. This updated version of OpenLDAP utilizes Network Security Services (NSS) cryptographic libraries, replacing OpenSSL.
TigerVNC provides client and server software for Virtual Network Computing (VNC). VNC is a remote display system, allowing a user to view a computing desktop environment over a network connection.TigerVNC is updated to version 1.1.0, providing many bugfixes enhanced encryption support.
tuned is a system tuning daemon that monitors system components and dynamically tunes system settings. Utilizing ktune (the static mechanism for system tuning), tuned can monitor and tune devices (e.g. hard disk drives and ethernet devices). In Red Hat Enterprise Linux 6.1, the tuned tuning profiles now include support for the s390x architectures.
A. Revision History
|Revision 1-1||2015-02-25||Laura Bailey|
|Revision 0-40.2.400||2013-10-31||Rüdiger Landmann|
|Revision 0-40.2||Thu Dec 13 2012||Martin Prpič|
|Revision 0-39||Fri May 20 2011||Ryan Lerch|
|Revision 1-0||Tue Mar 22 2011||Ryan Lerch|