Oracle Linux 6.1 Release Notes
Updated May. 2011
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Introduction
This document covers the following topics regarding Oracle Linux 6.
* Changes from the upstream release <#Changes_from_Upstream_Release>
o Packages modified from upstream release <#Packages_modified>
o Packages removed from upstream release <#Packages_removed>
o New packages added by Oracle <#New_Packages_added_>
* Kernel <#Kernel_and_Driver_Updates>
o Unbreakable Enterprise Kernel <#ook_introduction>
+ Introduction <#ook_introduction>
+ Driver Updates <#ook_driver_updates>
+ Features <#ook_new_feature>
* Known Issues <#known_issues>
* Technology Preview Features <#technology_preview>
* Unbreakable Linux Support <#ULS>
For the latest updates please refer to the online version of release
notes available at:
http://oss.oracle.com/ol6/docs/
*NOTE*: An upgrade of Oracle Linux from a beta release is not supported.
Further, an in-place upgrade between major versions of Oracle Linux is
not supported. Oracle does not recommend an upgrade from earlier major
versions of Oracle Linux even though anaconda provides an option to do
this upgrade.A fresh installation is strongly recommended rather than a
system upgrade between major versions. Customers who want to use new
features in Unbreakable Enterprise Kernel can do so without upgrading to
Oracle Linux 6 as Oracle Linux 5.6 already includes Unbreakable
Enterprise Kernel.
Changes from the Upstream Release
Packages modified from upstream release
The following packages are modified from the upstream release. All
changes are trademark and look/feel related unless otherwise noted below
under the specific package.
* PakageKit
* abrt
* anaconda
* basesystem
* compat-glibc
* efax
* filesystem
* firefox
* firstboot
* gdm
* gnome-desktop
* grubby
* gstreamer
* httpd
* initscripts
* iscsi-initiator-utils
* kabi-whitelists
* kabi-yum-plugins
* kdeadmin
* kdebase-workspace
* kexec-tools
* libvirt
* libxml2
* libxslt
* luci
* mkbootdisk
* mod_auth_kerb
* nmap
* nss
* openssl098e
* pilot-link
* piranha
* python-virtinst
* plymouth
* qpid-cpp
* redhat-bookmarks
* redhat-indexhtml
* redhat-lsb
* report
* rhnsd
* rhn-client-tools — updated for Unbreakable Linux Network (ULN) support
* rhnlib
* selinux-policy
* setroubleshoot
* setroubleshoot-plugins
* sos
* system-config-date
* system-config-date-docs
* system-config-kickstart
* system-config-network
* system-config-services
* system-config-services-docs
* system-config-users-docs
* system-icon-theme
* systemtap
* tog-pegasus
* wireshark — ocfs2-related fix
* xsane
* xulrunner
* yum
* yum-rhn-plugin
Packages removed from upstream release
The following packages have been removed.
* python-rhsm
* Red_Hat_Enterprise_Linux-Release_Notes-6-as-IN
* Red_Hat_Enterprise_Linux-Release_Notes-6-bn-IN
* Red_Hat_Enterprise_Linux-Release_Notes-6-de-DE
* Red_Hat_Enterprise_Linux-Release_Notes-6-en-US
* Red_Hat_Enterprise_Linux-Release_Notes-6-es-ES
* Red_Hat_Enterprise_Linux-Release_Notes-6-fr-FR
* Red_Hat_Enterprise_Linux-Release_Notes-6-gu-IN
* Red_Hat_Enterprise_Linux-Release_Notes-6-hi-IN
* Red_Hat_Enterprise_Linux-Release_Notes-6-it-IT
* Red_Hat_Enterprise_Linux-Release_Notes-6-ja-JP
* Red_Hat_Enterprise_Linux-Release_Notes-6-kn-IN
* Red_Hat_Enterprise_Linux-Release_Notes-6-ko-KR
* Red_Hat_Enterprise_Linux-Release_Notes-6-ml-IN
* Red_Hat_Enterprise_Linux-Release_Notes-6-mr-IN
* Red_Hat_Enterprise_Linux-Release_Notes-6-or-IN
* Red_Hat_Enterprise_Linux-Release_Notes-6-pa-IN
* Red_Hat_Enterprise_Linux-Release_Notes-6-pt-BR
* Red_Hat_Enterprise_Linux-Release_Notes-6-ru-RU
* Red_Hat_Enterprise_Linux-Release_Notes-6-si-LK
* Red_Hat_Enterprise_Linux-Release_Notes-6-ta-IN
* Red_Hat_Enterprise_Linux-Release_Notes-6-te-IN
* Red_Hat_Enterprise_Linux-Release_Notes-6-zh-CN
* Red_Hat_Enterprise_Linux-Release_Notes-6-zh-TW
* redhat-logos
* redhat-release
* subscription-manager
New Packages added by Oracle
The following packages have been added to the base release
* kernel-uek
* ocfs2-tools
* ofa-2.6.32-100.34.1.el5uek
* oracle-logos
* oracleasm-support
* oraclelinux-release
* oraclelinux-release-notes
Kernel
Oracle Linux 6 ships with two sets of kernel packages:
* Unbreakable Enterprise Kernel [kernel-uek-2.6.32-100.34.1.el6uek]
o Installed and booted by default
* Red Hat compatible Kernel [kernel-2.6.32-131.0.15.el6]
o Installed by default
*Note*:Oracle Linux 6.1 includes both a 32 bit and a 64 bit Unbreakable
Enterprise Kernel. By default, both the Unbreakable Enterprise Kernel
and the Red Hat Compatible Kernel are installed, and the system boots
the Unbreakable Enterprise Kernel by default. If needed, /etc/grub.conf
can be modified to make the system boot with the Red Hat Compatible
Kernel by default.
Unbreakable Enterprise Kernel
The Unbreakable Enterprise Kernel is based on the upstream kernel
2.6.32.21 stable source tree with additional performance improvements,
including:
* improved IRQ balancing
* reduced lock contention across the kernel
* improved network I/O via receive packet steering and RDS improvements
* improved virtual memory performance
Oracle Linux 6.1 includes both a 32 bit and a 64 bit Unbreakable
Enterprise Kernel. The Unbreakable Enterprise Kernel is the default
kernel after installation.
Driver Updates
Network Drivers updates
* Added support for paravartualized driver in a hardware virtualized
guest on Oracle VM
* Updated tg3 to version 3.113.
* Updated bnx2 driver and firmware to version 2.1.6
* Added support for bnx2fc (version 1.0.2)
* Updated bnx2x to version 1.62.00-6
* Updated cnic to version 2.2.14
* Updated bnx2i to version 2.6.2.3
* Updated be2net to version 2.103.298r
* Updated e100 to version 3.5.24-k2
* Updated e1000e to version 1.2.20-k2
* Updated ixgbe to version 3.2.10-NAPI
* Updated igb to version 3.0.6-k2
* Updated cxgb3 to version 1.1.4-ko
* Added Chelsio T4(cxgb4) support (version 1.3.0-k0)
* Updated bna to version 2.3.2.3r.
* Updated igbvf to version 1.0.8-k0
* Updated ixgbevf to version 1.0.19-k0
* Updated qlge to version v1.00.00.27.00.00-01
* Updated vxge to version 2.0.9-20840-k
* Added qlcnic version 5.0.15.2
* Updated enic to version 2.1.1.13
* Updated netxen_nic to version 4.0.75
SCSI Drivers updates
* Added support for paravartualized driver in a hardware virtualized
guest on Oracle VM
* Updated cxgb3i to version 2.0.0
* Added cxgb4i (version 0.9.1)
* Updated lpfc to version 0:8.3.5.30.1p
* Updated megaraid_sas to version 00.00.05.34-rc1
* Updated mpt2sas to version 08.101.00.00
* Updated mptsas to version 3.04.18
* Updated ipr to version 2.5.1
* Updated fnic to version 1.5.0.1
* Updated be2iscsi to version 2.103.298.0
* Updated bfa to version 2.3.2.3
* Updated hpsa to version 2.0.2-3
* Updated cciss to version 3.6.28-RH
* Updated qla4xxx to version v5.02.12.00.32.01-c0
* Updated qla2xxx driver to version v8.03.07.03.32.1-k
* Added Intel SCU driver version 1.0
Infiniband
* Added QLogic IB support
* Updated nes to 1.5.0.0
Features
* OpenFabrics Enterprise Distribution (OFED) 1.5.1
OFED implements Remote Direct Memory Access (RDMA) and kernel
bypass mechanisms to deliver high-efficiency computing,
wire-speed messaging, ultra-low microsecond latencies and fast
I/O for servers, block storage and file systems.
* OCFS2 1.6
The Unbreakable Enterprise Kernel includes the OCFS2 1.6
kernel module. New features include:
o JBD2 support
o Extended attributes
o POSIX ACLs
o Security attributes
o Metadata checksums
o Indexed directories
o REFLINKs
For more details, see the OCFS2 1.6 User's Guide
<http://oss.oracle.com/projects/ocfs2/dist/documentation/v1.6/ocfs2-1_6-usersguide.pdf>
* DIF/DIX support
The Linux data integrity framework (DIF) enables applications
or kernel subsystems to attach metadata to I/O operations,
allowing devices that support DIF to verify the integrity
before passing them further down the stack and physically
committing them to disk. Data Integrity Extensions or DIX is a
hardware feature that enables exchange of protection metadata
between host operating system and HBA.
* Tickless kernel
The Unbreakable Enterprise Kernel is tickless. In the tickless
kernel, timer interrupts are performed on demand rather than
at a predetermined frequency. This allows CPUs to stay in a
low power state when the system is idle, reducing overall
power consumption
* Task Control Groups (TCG)
TCG can track and group processes into user-defined cgroups so
that the operating system can treat them as whole and perform
scheduling, accounting, and resourceallocation accordingly.
For example, using TCG, you can associate a set of CPU cores
and memory nodes to a group of processes that makeup an
application or a group of applications. This enables
subsetting larger systems, more fine grained control over CPU
and memory, and isolation of applications.
* Performance Counters for Linux (PCL)
The performance counter subsystem keeps track of hardware and
software events without affecting performance and enables you
to do tracing and performance analysis. Included is a tool
called perf for analysis.
* SSD Detection
The kernel block layer will detect devices that claim to be
fast,solid state storage and tune itself accordingly. The
result of this detection can be found in:
/sys/block/xxx/queue/rotational
Where xxx is the block device. Echoing a 0 or a 1 into this
file will force the value to off or on. When assuming a device
is an SSD, the block layer will try harder to immediately
dispatch the IO to the device.
* IO affinity
IO affinity ensures processing of a completed IO is handled by
the same CPU that initiated the IO. It can have a fairly large
impact on performance, especially on large NUMA machines. IO
affinity is turned on by default, but it can be controlled via
the tunable in /sys/block/xxx/queue/rq_affinity. For example,
the following will turn IO affinity on:
echo 1> /sys/block/sda/queue/rq_affinity
* Receive packet steering (RPS)
RPS distributes the load of received packet processing across
multiple CPUs. This solution allows protocol processing (e.g.
IP and TCP) to be performed on packets in parallel. This
removes a bottleneck when a single core is saturated
processing network interrupts. To enable receive packet
steering for the interface xxx, place a CPU mask into
/sys/class/net/xxx/queues/rx-0/rps_cpus
The cpu mask takes the same form as the masks for the taskset
command. For example:
echo 0x55> /sys/class/net/eth0/queues/rx-0/rps_cpus
* fallocate()
fallocate() is a new system call which will allow applications
to preallocate space to any file(s) in a file system.
Applications can get a guarantee of space for particular
file(s) - even if later the system becomes full. Using this
method of allocation can dramatically speed up the creation of
large files such as those used for virtual machine images.
Known Issues
1. Hardware virtualized (HVM) guests with Unbreakable Enterprise Kernel
always use paravirtualized (PV) drivers
Unbreakable Enterprise Kernel version kernel-uek-2.6.32-100.34.1 adds
support for paravirtualized drivers in a HVM guest on Oracle VM.
Starting with this kernel version, the default is to present only
paravirtualized drivers when running in a hardware virtualized guest.
To run kernel-uek --including the drivers-- fully hardware virtualized,
an additional kernel boot parameter "xen_emul_unplug=never" must be
added to the boot parameters in /etc/grub.conf:
kernel /vmlinuz-2.6.32-100.34.1.el6uek ro root=/dev/VolGroup00/LogVol00 xen_emul_unplug=never
Adding this kernel boot parameter makes the kernel also present the
emulated drivers as it did before (e.g. the 8139cp network driver).
2. Incorrect package count (11684244)
Selecting all packages in certain groups during installation
might not show the correct count.
3. Default reverse path filtering mode affects certain Oracle
products (10649976)
Oracle Linux 6 defaults to strict reverse path filtering. Some
Oracle products and network storage devices work more reliably
when using loose reverse path filtering. To enable loose mode
reverse path filtering, issue the following command (assuming
you are changing settings for the network interface called
eth1). The default setting is 1.
sysctl net.ipv4.conf.eth1.rp_filter=2
4. Receive Packet Steering errors for certain network operations
(11071685)
Certain network operations that utilize receive packet
steering could cause errors on the system.
5. Spurious udev messages during restore of a failed path (11682171)
When failed paths are restored in a multipath configuration,
you may see udevd-work error messages in /var/log/messages.
The failed paths do get restored despite these messages.
6. Default NFS v4 mount options
The default NFS mount option has changed to NFS v4. To mount
an NFS volume using NFS v3 (the default in Oracle Linux 5),
use the following mount options:
-o vers=3,mountproto=tcp
7. Setting serial console in a hardware virtualized (HVM) guest
To set the serial console a hardware virtualized (HVM) guest
use following settings in the guest:
* On the kernel boot line in grub.conf, add:
console=tty0 console=ttyS0,57600n8
* add the following to /etc/securetty
ttyS0
* add the following to /etc/sysconfig/init
ACTIVE_CONSOLES=/dev/tty[0-6]
8. Unbreakable Linux Network
After an install of Oracle Linux 6, the screens after the
first reboot will guide you to register your system to the
Unbreakable Linux Network (ULN). If you did not configure your
network during the initial installation, the registration
process to ULN will not succeed. In this case, you should
configure your network by running NetworkManager first (as
root). Then restart the ULN registration by running
uln_register (as root).
9. Console appears to hang while booting on certain systems (10094052)
On some hardware, the console may appear to hang during the
boot process after starting udev. But the system does boot up
properly and is accessible. A workaround to this problem is to
add nomodeset as a kernel boot parameter in /etc/grub.conf:
kernel /vmlinuz-2.6.32-100.34.1.el6uek.x86_64 ro root=/dev/sd0 nomodeset
10. Default IO scheduler
For the Unbreakable Enterprise Kernel, the default IO
scheduler is the 'deadline' scheduler.
For the Red Hat Compatible Kernel, the default IO scheduler is
the 'cfq' scheduler.
11. sched_yield() settings for CFS
For the Unbreakable Enterprise Kernel,
kernel.sched_compat_yield=1 by default.
For the Red Hat Compatible Kernel, kernel.sched_compat_yield=0
by default.
12. High IO loads on NFS using mmap may fail (11071875)
In some instances, large IO loads on NFS that use mmap may
fail and cause the kernel to panic with a message like:
kernel BUG at mm/truncate.c:469!
13. Warning message when kdump starts
When kdump starts, you may see the following warning message:
WARNING: No modules scsi_mod found for kernel 2.6.32-100.34.1.el6uek.x86_64, continuing anyway
This warning can be ignored. The kdump service does get
started and a vmcore does get generated.
Technology Preview Features
The following Technology Preview features are currently not supported
under Oracle Linux 6 and may not be functionally complete:
* Open Multicast Ping (Omping)
* Matahari
* System Information Gatherer and Reporter (SIGAR)
* fsfreeze
* DIF/DIX support
* Filesystem in Userspace
* btrfs
* LVM Application Programming Interface (API)
* FS-Cache
* IPv6 support in IPVS
* pacemaker
* XFS
* upd-unicast support
* certmonger
* TPM
* Brocade BFA Driver
* SR-IOV on the be2net driver
* Kernel Media support (Tech Preview)
* Remote Audit Logging
* Linux (NameSpace) Container [LXC]
* Error Detection And Correction (EDAC) driver interface
* Diagnostic pulse for the fence_ipmilan agent
These features are not suitable for production use. However, these
features are included to provide the feature with wider exposure.
Unbreakable Linux Support
Oracle Linux 6 not longer contains up2date for access to Unbreakable
Linux Network. Instead packages are managed using Yum. To register with
ULN, use the following command:
# uln_register
To access Linux updates via Unbreakable Linux Network, you must purchase
a Linux support subscription. For more information please visit
http://linux.oracle.com <http://linux.oracle.com/>