Oracle® Linux
Release Notes for Unbreakable Enterprise Kernel Release 2 Quarterly
Update 5
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E48381-02
September 2013
Abstract
This document contains information on Quarterly Update 5 to the
Unbreakable Enterprise Kernel Release 2. This document may be
updated after it is released. To check for updates to this
document, and to view other Oracle documentation, refer to the
Documentation section on the Oracle Technology Network (OTN) Web
site:
http://www.oracle.com/technology/documentation/
This document is intended for users and administrators of Oracle
Linux. It describes potential issues and the corresponding
workarounds you may encounter while using the Unbreakable
Enterprise Kernel Release 2 with Oracle Linux 5 and Oracle Linux
6. Oracle recommends that you read this document before installing
or upgrading the Unbreakable Enterprise Kernel Release 2.
Document generated on: 2013-09-28 (revision: 1240)
_______________________________________________________
Preface
The Oracle Linux Unbreakable Enterprise Kernel Release Notes
provides a summary of the new features, changes, and fixed and
known issues in the Unbreakable Enterprise Kernel Release 2.
Audience
This document is written for system administrators who want to use
the Unbreakable Enterprise Kernel with Oracle Linux. It is assumed
that readers have a general understanding of the Linux operating
system.
Documentation Accessibility
For information about Oracle's commitment to accessibility, visit
the Oracle Accessibility Program website at
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hearing impaired.
Related Documents
The latest version of this document and other documentation for
this product are available at:
http://www.oracle.com/technetwork/server-storage/linux/documentati
on/index.html.
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Chapter 1. New Features and Changes
The Unbreakable Enterprise Kernel Release 2 (UEK R2) is Oracle's
second major release of its heavily tested and optimized operating
system kernel for Oracle Linux 5 and Oracle Linux 6. See the
initial Oracle Unbreakable Enterprise Kernel Release 2 Release
Notes (https://oss.oracle.com/ol6/docs/RELEASE-NOTES-UEK2-en.html)
for a detailed description of the differences between UEK R2 and
the first version of the Unbreakable Enterprise Kernel.
The 2.6.39-400.209.1 release is the fifth quarterly driver update
release, which also includes bug and security fixes.
Note
The version number displayed by the kernel and on the RPM packages
is 2.6.39. This was done to avoid potential breakage of certain
low-level utilities of the Oracle Linux distribution (also known
as the plumbing) that potentially cannot cope with the new 3.x
version scheme. Regular Linux applications are usually neither
aware of nor affected by Linux kernel version numbers.
1.1. Notable Changes
* Xsigo virtual host adapter and network drivers to support
Oracle SDN (Software Defined Network), previously known as
Xsigo Fabric Accelerator.
* LSI Fusion-MPT SAS 3.0 driver to support up to 12 Gb/s host
controllers.
1.2. Xen Improvements
Relative to quarterly update 4, several improvements have been
incorporated into the Unbreakable Enterprise Kernel to support Xen
usage:
* Fixes for EDD, x2apic, XenBus, and PVHVM vCPU hotplug issues.
* The indirect-descriptor feature, which increases throughput
and reduces latency for block I/O.
1.3. Driver Updates
The Unbreakable Enterprise Kernel supports a wide range of
hardware and devices. In close cooperation with hardware and
storage vendors, several device drivers have been updated by
Oracle.
1.3.1. Storage Adapter Drivers
Adaptec
* AACRAID driver (aacraid) updated to 1.2-0[30200]-ms.
Cisco
* Cisco FCoE HBA Driver (fnic) updated to 1.5.0.45.
Emulex
* Fibre Channel HBA driver (lpfc) updated to 0:8.3.7.26.3p.
Intel
* C600 serial attached SCSI (SAS) module (isci) updated to
1.0.0.
LSI
* LSI Fusion-MPT base driver (mptbase) updated to 4.28.20.02.
* LSI Fusion-MPT ioctl driver (mptctl) updated to 4.28.20.02.
* LSI Fusion-MPT Fibre Channel host driver (mptfc) updated to
4.28.20.02.
* LSI Fusion-MPT IP Over Fibre Channel driver (mptlan) updated
to 4.28.20.02.
* LSI Fusion-MPT SAS driver (mptsas) updated to 4.28.20.02.
* LSI Fusion-MPT SCSI host driver (mptscsih) updated to
4.28.20.02.
* LSI Fusion-MPT SPI host driver (mptspi) updated to 4.28.20.02.
* LSI Fusion-MPT SAS 2.0 driver (mpt2sas) updated to
17.00.01.00.
* LSI Fusion-MPT SAS 3.0 driver (mpt3sas) version 3.00.00.00
added. Supports up to 12 Gb/s host controllers.
MegaRAID
* MegaRAID SAS driver (megaraid_sas) updated to 06.600.18.00.
QLogic
* iSCSI driver (qla4xxx) updated to 5.03.00.03.06.02-uek2.
Supports Open-iSCSI.
Xsigo
* Core services module driver (xscore) version 6.0.r7269 added.
Required by all other Xsigo modules.
* Virtual HBA driver (xsvhba) version 6.0.r7269 added.
1.3.2. Network Adapter Drivers
Broadcom
* Tigon3 Ethernet adapter driver (tg3) updated to 3.131d.
Emulex
* Blade Engine 2 10Gbps adapter driver (be2net) updated to
4.6.63.0u.
Intel
* PRO/1000 PCI-Express Gigabit network adapter driver (e1000e)
updated to 2.4.14.
* Gigabit Ethernet network adapter driver (igb) updated to
4.3.0.
* Gigabit Linux driver (igbvf) updated to 2.3.2. Provides
82576-based virtual function devices on kernels that support
Single Root I/O Virtualization (SR-IOV).
* 10 Gigabit PCI-Express network adapter driver (ixgbe) updated
to 3.15.1.
QLogic
* 1/10 GbE Converged/Intelligent Ethernet Adapter driver
(qlcnic) updated to 5.2.43.
Xsigo
* Core services module driver (xscore) version 6.0.r7269 added.
Required by all other Xsigo modules.
* Virtual Ethernet driver (xve) added.
* Virtual NIC driver (xsvnic) version 0.316.0.r7269 added.
1.4. Technology Preview
The following features included in the Unbreakable Enterprise
Kernel Release 2 are still under development, but are made
available for testing and evaluation purposes.
* 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.
* Linux Containers (lxc)
Based on the Linux Cgroups and name spaces functionality,
containers allow you to safely and securely run multiple
applications or instances of an operating system on a single
host without risking them interfering with each other.
Containers are lightweight and resource-friendly, which saves
both rack space and power. In order to get started with
containers, you need to install the lxc package, which is
included in the package repository of the Unbreakable
Enterprise Kernel.
* Transcendent memory
Transcendent Memory (tmem for short) provides a new approach
for improving the utilization of physical memory in a
virtualized environment by claiming underutilized memory in a
system and making it available where it is most needed. From
the perspective of an operating system, tmem is fast
pseudo-RAM of indeterminate and varying size that is useful
primarily when real RAM is in short supply. To learn more
about this technology and its use cases, see the Transcendent
Memory project page at http://oss.oracle.com/projects/tmem/.
1.5. Compatibility
Oracle Linux maintains user-space compatibility with Red Hat
Enterprise Linux, which is independent of the kernel version
running underneath the operating system. Existing applications in
user space will continue to run unmodified on the Unbreakable
Enterprise Kernel Release 2 and no re-certifications are needed
for RHEL certified applications.
From UEK R2 quarterly update 3 (2.6.39-400) onward, support for
IB, OFED, and RDS is integrated into the kernel. The OFED userland
RPMs continue to be provided, but the kernel-ib and ofa-kernel
RPMs are no longer required.
The kernel ABI remains unchanged in all updates to UEK R2
subsequent to quarterly update 3.
To minimize impact on interoperability during releases, the Oracle
Linux team works closely with third-party vendors whose hardware
and software have dependencies on kernel modules. However, to
allow the introduction of new drivers, there might be instances
where changes must be made. Before installing this update, verify
the support status of this release with your application vendor.
Chapter 2. Fixed and Known Issues
This chapter describes the fixed and known issues for the
Unbreakable Enterprise Kernel Release 2.
Important
Run the yum update command regularly to ensure that the latest bug
fixes and security errata are installed on your system.
2.1. Fixed Issues
This update includes minor fixes for various software issues as
well as security fixes for several CVEs. There are no major fixed
issues of note.
2.2. Known Issues
This section describes known issues in this update.
ACPI
One some systems you might see ACPI-related error messages in
dmesg similar to the following:
ACPI Error: [CDW1] Namespace lookup failure, AE_NOT_FOUND
ACPI Error: Method parse/execution failed [_SB_._OSC||\||]
ACPI Error: Field [CDW3] at 96 exceeds Buffer [NULL] size 64
(bits)]]>
These messages, which are not fatal, are caused by bugs in the
BIOS. Contact your system vendor for a BIOS update. (Bug ID
13100702)
ASM
Calling the oracleasm init script, /etc/init.d/oracleasm, with the
parameter scandisks can lead to error messages about missing
devices similar to the following:
oracleasm-read-label: Unable to open device "device": No such file or
directory
However, the device actually exists. You can ignore this error
message, which is triggered by a timing issue. Only use the init
script to start and stop the oracleasm service. All other options,
such as scandisks, listdisk, and createdisk, are deprecated. For
these and other administrative tasks, use /usr/sbin/oracleasm
instead. (Bug ID 13639337)
bnx2x driver
When using the bnx2x driver in a bridge, disable Transparent
Packet Aggregation (TPA) by including the statement options bnx2x
disable_tpa=1 in /etc/modprobe.conf. (Bug ID 14626070)
Btrfs
* Together with the UEK R2 kernel in quarterly update 4, a new
version of the user-space btrfs-progs package
(btrfs-progs-0.20-1.4) was provided on the ol6_latest channel.
This package enabled command-line access to new btrfs
features. If you install this version or later of the
btrfs-progs package on a system that does not have an upgraded
kernel, most of the new command functionality supported by the
package fails with the error Inappropriate ioctl for device.
The exception is the -l option to mkfs.btrfs, which requires
version 2.6.39-400.109.1 or later of the Unbreakable
Enterprise Kernel. Do not use this option with an non-upgraded
kernel as correct functioning of the file system cannot be
guaranteed. Although the leaf size appears to be set
successfully, there is a risk of data corruption if you
subsequently use the resulting file system. (Bug ID 16920640)
* If you use the --alloc-start option with mkfs.btrfs to specify
an offset for the start of the file system, the size of the
file system should be smaller but this is not the case. It is
also possible to specify an offset that is higher than the
device size. This bug is present in the user-space btrfs-progs
package (btrfs-progs-0.20-1.4). (Bug ID 16946255)
* The usage information for mkfs.btrfs reports raid5 and raid6
as possible profiles for both data and metadata. However, the
kernel does not support these features and cannot mount file
systems that use them. This bug is present in the user-space
btrfs-progs package (btrfs-progs-0.20-1.4). (Bug ID 16946303)
* The btrfs filesystem balance command does not warn that the
RAID level can be changed under certain circumstances, and
does not provide the choice of cancelling the operation. (Bug
ID 16472824)
* Converting an existing ext2, ext3, or ext4 root file system to
btrfs does not carry over the associated security contexts
that are stored as part of a file's extended attributes. With
SELinux enabled and set to enforcing mode, you might
experience many permission denied errors after reboot, and the
system might be unbootable. To avoid this problem, enforce
automatic file system relabeling to run at bootup time. To
trigger automatic relabeling, create an empty file named
.autorelabel (for example, by using touch) in the file
system's root directory before rebooting the system after the
initial conversion. The presence of this file instruct SELinux
to recreate the security attributes for all files on the file
system. If you forget to do this and rebooting fails, either
temporarily disable SELinux completely by adding selinux=0 to
the kernel boot parameters, or disable enforcing of the
SELinux policy by adding enforcing=0. (Bug ID 13806043)
* A failing RAID1 disk can result in a kernel panic with the
error message:
BTRFS error (device (null)) in btree_writepage_io_failed_hook:3662: \
IO failure (Error occurred while writing out btree at offse
t).
(Bug ID 16262571)
* The btrfs filesystem defragment command exits with an exit
code of 20 even if it succeeds. (Bug ID 13714531)
* Commands such as du can show inconsistent results for file
sizes in a btrfs file system when the number of bytes that is
under delayed allocation is changing. (Bug ID 13096268)
* Btrfs has a limit of 237 or fewer hard links to a file from a
single directory. The exact limit depends on the number of
characters in the file name. The limit is 237 for a file with
up to eight characters in its file name; the limit is lower
for longer file names. Attempting to create more than this
number of links results in the error Too many links. You can
create more hard links to the same file from another
directory. (Bug ID 16278563)
* If you run the btrfs quota enable command on a non-empty file
system, any existing files do not count toward space usage.
Removing these files can cause usage reports to display
negative numbers and the file system to be inaccessible. The
workaround is to enable quotas immediately after creating the
file system. If you have already written data to the file
system, it is too late to enable quotas. (Bug ID 16569350)
* The btrfs quota rescan command is not currently implemented.
The command does not perform a rescan and returns without
displaying any message.
* The functionality to limit the space that is available to a
quota group before compressing the subvolume is not yet
implemented. The -c option (limit the space after compression)
to the btrfs qgroup limit command is implicitly enabled. (Bug
ID 16569387)
* The copy-on-write nature of btrfs means that every operation
on the file system initially requires disk space. It is
possible that you cannot execute any operation on a disk that
has no space left; even removing a file might not be possible.
The workaround is to run sync before retrying the operation.
If this does not help, remount the file system with the -o
nodatacow option and delete some files to free up space. See
https://btrfs.wiki.kernel.org/index.php/ENOSPC.
* The seed-device functionality of btrfs causes a kernel panic
when the btrfs device add command is run. There is currently
no known workaround for this issue. (Bug ID 17334251)
CPU microcode update failures on PVM/PVHVM guests
When running Oracle Linux with UEK R2, you might see error
messages in dmesg or /var/log/messages similar to this one:
microcode: CPU0 update to revision 0x6b failed.
You can ignore this warning. You do not need to upgrade the
microcode for virtual CPUs as presented to the guest. (Bug ID
12576264, 13782843)
DHCP lease is not obtained at boot time
If DHCP lease negotiation takes more than 5 seconds at boot time,
the following message is displayed:
ethX: failed. No link present. Check cable?
If the ethtool ethX command confirms that the interface is
present, edit /etc/sysconfig/network-scripts/ifcfg-ethX and set
LINKDELAY=N, where N is a value greater than 5 seconds (for
example, 30 seconds). Alternatively, use NetworkManager to
configure the interface. (Bug ID 16620177)
Emulex OneConnect UCNA Firmware Flashing
The request_firmware interface to the Emulex Ethernet driver for
Emulex OneConnect adapters supports flash updating of the UCNA
firmware image.
Oracle Linux 5 systems with the Unbreakable Enterprise Kernel
require the ethtool-6-4.0.1.el5.arch.rpm version of the ethtool
package, where arch is i386 or x86_64 as appropriate. The package
is available from the ol5_i386_UEK_latest and
ol5_x86_64_UEK_latest channels on the Unbreakable Linux Network
(Advisory ELBA-2013-2544
(https://oss.oracle.com/pipermail/el-errata/2013-August/003651.htm
l), released Aug 29, 2013) or from Oracle Public Yum at
http://public-yum.oracle.com/repo/OracleLinux/OL5/latest.
Oracle Linux 6 systems with the Unbreakable Enterprise Kernel do
not require a package update.
Note
You can update the firmware image while the UCNA is online and
passing network or storage traffic. However, you must reboot the
system for the new firmware image to take effect.
To update the UCNA firmware image:
1. Copy the firmware image file (for example, be3flash.ufi) to
the /lib/firmware directory:
# cp be3flash.ufi /lib/firmware
2. Start the update process:
# ethtool -f ethN be3flash.ufi 0
where ethN is the name of the interface.
3. Reboot the system to enable the new firmware image to take
effect.
Firmware warning message
You can safely ignore the following firmware warning message that
might be displayed on some Sun hardware:
[Firmware Warn]: GHES: Poll interval is 0 for generic hardware error
source:
1, disabled.
(Bug ID 13696512)
I/O scheduler
The Unbreakable Enterprise Kernel uses the deadline scheduler as
the default I/O scheduler. For the Red Hat Compatible Kernel, the
default I/O scheduler is the cfq scheduler.
InfiniBand warning messages when disabling a switch port
You might see the following warning messages if you use the
ibportstate disable command to disable a switch port:
ibwarn: [2696] _do_madrpc: recv failed: Connection timed out
ibwarn: [2696] mad_rpc: _do_madrpc failed; dport (Lid 38)
ibportstate: iberror: failed: smp set portinfo failed
You can safely ignore these warnings. (Bug ID 16248314)
libfprint
The following message might appear in dmesg or /var/log/messages:
WARNING! power/level is deprecated; use power/control instead.
The USB subsystem in UEK R2 deprecates the power/level sysfs
attribute in favor of the power/control attribute. The libfprint
fingerprinting library triggers this warning via udev rules that
try to use the old attribute first. You can safely ignore this
warning. The setting of the appropriate power level still
succeeds. (Bug ID 13523418)
Multipathed root disk
At boot time, the root file system is not writable when the
multipathing service starts. As a result, the system cannot
automatically generate the file /etc/multipath/wwids and the
console displays a message similar to the following:
Cannot open file [/etc/multipath/wwids] readonly: No such file or dir
ectory
You can safely ignore this warning. The subsequent post-boot
operation of multipathd and device-mapper-multipath is not
affected.
To prevent this warning message from recurring, enter the
following command as root to generate /etc/multipath/wwids after
the system has booted:
# multipath -l
(Bug ID 17395420, 16076888)
NFSv4 and open(2) flag combinations that can cause a process to hang
If you specify both the O_RDONLY and O_TRUNC flags when opening a
regular file in a mounted NFS version 4 file system,the calling
process hangs. The workaround is not to use this combination of
flags with regular files. O_TRUNC is intended for use with regular
files where the open mode allows writing. (Bug ID 17412390)
Nouveau kernel driver is not compatible with NVIDIA graphics driver
After upgrading to UEK R2, the NVIDIA driver upgrade script does
not correctly blacklist the Nouveau kernel driver. To blacklist
the driver, append rdblacklist=nouveau nouveau.modeset=0 to the
kernel boot parameters in /boot/grub/grub.conf.
NUMA warning messages on a non-NUMA system
You can safely ignore the following warning messages in dmesg and
/var/log messages if you see them on a non-NUMA system:
kernel: NUMA: Warning: node ids are out of bound, from=-1 to=-1 dista
nce=10
hcid[4293]: Register path:/org/bluez fallback:1
kernel: No NUMA configuration found
(Bug ID 13711370)
pcspkr driver error message
You can safely ignore the following error message:
Error: Driver 'pcspkr' is already registered, aborting...
The message arises from an alias conflict between snd-pcsp and
pcspkr. To prevent the message from being displayed, add the
following line to /etc/modprobe.d/blacklist.conf:
blacklist snd-pcsp
(Bug ID 10355937)
sched_yield() settings for CFS
For the Unbreakable Enterprise Kernel, kernel.sched_compat_yield=1
is set by default. For the Red Hat Compatible Kernel,
kernel.sched_compat_yield=0 is used by default.
Soft lockup errors when booting
When upgrading or installing the UEK R2 kernel on fast hardware,
usually with SAN storage attached, the kernel can fail to boot and
BUG: soft lockup messages are displayed in the console log. The
workaround is to increase the baud rate from the default value of
9600 by amending the kernel boot line in /boot/grub/grub.conf to
include an appropriate console setting, for example:
console=ttyS0,115200n8
A value of 115200 is recommended as smaller values such as 19200
are known to be insufficient for some systems (for example, see
http://docs.oracle.com/cd/E19045-01/blade.x6220/820-0048-18/sp.htm
l#0_pgfId-1002490). If the host implements an integrated system
management infrastructure, such as ILOM on Sun and Oracle systems
or iLO on HP systems, configure the integrated console baud rate
to match the setting for the host system. Otherwise, the
integrated console is likely to display garbage characters. (Bug
ID 17064059, 17252160)
Support for large memory 32-bit systems
Releases of Oracle Linux prior to Oracle Linux 5 supplied a
hugemem kernel to allow a system to address up to 64 GB of memory
in 32-bit mode. The hugemem kernel is no longer available in
Oracle Linux 5 and later releases.
The Unbreakable Enterprise Kernel (UEK) supports a maximum of 16
GB of memory for 32-bit kernels on bare metal and hardware
virtualized machine (HVM) systems, and 8 GB for fully
paravirtualized machine (PVM) systems. 32-bit PVM guest operating
systems must be located in the first 128 GB of physical memory on
the host.
The Red Hat Compatible Kernel (RHCK) has the same limitations,
except that PVM systems can have up to 16 GB of memory. The
limitation of 8 GB for PVM on UEK was chosen for reasons of
reliability.
A 32-bit system uses the PAE (physical address extension) memory
feature to map physical memory beyond 4 GB into the 32-bit address
space that is available to each process. A 64-bit system can
address memory beyond 4 GB without requiring an extra layer of
memory abstraction.
Oracle Linux on x86_64 includes 32-bit libraries, which allow
applications built for both 64-bit and 32-bit Linux to run on the
same system. This capability provides scalability to virtually
unlimited memory sizes, while retaining the ability to run 32-bit
applications. Oracle recommends this configuration for any system
with more than 4 GB of memory. (Bug ID 16974301)
Transparent Huge Pages
This update removes the Transparent Huge Pages (THP) feature.
Following extensive benchmarking and testing, Oracle found that
THP caused a performance degradation for some workloads of between
5 and 10%. This performance degradation was a result of a slower
memory allocator code path being used even when the applications
were not using THP. When the fact that huge pages are not
swappable was taken into account, the positive effect that THP
should provide was outweighed by its negative effects.
After installing this update, you cannot enable THP (for example,
by specifying kernel boot parameters). The THP settings under
/sys/kernel/mm/transparent_hugepage have also been removed. A
future update might contain an updated THP implementation which
resolves the performance issue.
Note
This change does not affect support for applications that use
explicit huge pages (for example, Oracle Database).
(Bug ID 17279055)
udev
A message similar to the following might be recorded in dmesg or
/var/log/messages at boot time:
udevd (pid): /proc/pid/oom_adj is deprecated, please use /proc/pid/oo
m_score_adj instead.
The udev process uses the deprecated oom_adj kernel interface to
prevent it from being killed if the system runs short of memory.
You can safely ignore the message as the action still succeeds. To
prevent the message from occurring, install the package
udev-147-2.42.el6.arch.rpm or higher for Oracle Linux 6, or
udev-095-14.29.0.1.el5.arch.rpm or higher for Oracle Linux 5. (Bug
ID 13655071, 13712009)
Virtualization
* When booting UEK R2 as a PVHVM guest, you can safely ignore
the following kernel message:
register_vcpu_info failed:
err=-38
(Bug ID 13713774)
* Under Oracle VM Server 3.1.1, migrating a PVHVM guest that is
running the UEK R2 Quarterly Update 5 kernel causes a
disparity between the date and time as displayed by date and
hwclock. The workaround post migration is either to run the
command hwclock --hctosys on the guest or to reboot the guest.
(Bug ID 16861041)
* Under Oracle VM Server 2.2.2, increasing the memory that is
assigned to an Oracle Linux 6 Update 4 x86_64 HVM guest
running UEK R2 Quarterly Update 5 causes the guest to reboot.
There is no known workaround for this issue. (Bug ID 17440635)
XFS
* Reading from or writing to a zero or null device on a
read-only XFS file system fails with the following error:
XFS_IOC_FSGEOMETRY: Inappropriate ioctl for device
(Bug ID 16970090)
* Newly created directories in an XFS file system do not inherit
their group setting from the parent directory on which the
setgid bit is set. (Bug ID 17423815)
Chapter 3. Installation and Availability
The Unbreakable Enterprise Kernel Release 2 Quarterly Update 5 can
be installed on Oracle Linux 5 Update 8 or newer, as well as
Oracle Linux 6 Update 2 or newer, both running either the Red Hat
compatible kernel or a previous version of the Unbreakable
Enterprise Kernel. If you are still running an older version of
Oracle Linux, first update your system to the latest available
update release.
The kernel images are available as binary RPM packages from
dedicated channels on Oracle's Unbreakable Linux Network (ULN) as
well as the Oracle Public Yum repository. Four channels are
available:
* Oracle Linux 5 (x86): ol5_i386_UEK_latest
* Oracle Linux 5 (x86_64): ol5_x86_64_UEK_latest
* Oracle Linux 6 (x86): ol6_i386_UEK_latest
* Oracle Linux 6 (x86_64): ol6_x86_64_UEK_latest
If your system is registered with ULN, make sure you subscribe it
to the appropriate UEK_latest channel.
For Oracle Public Yum, the appropriate UEK_latest channel is
automatically enabled in the yum respiratory file under
/etc/yum.repos.d when you install Oracle Linux 5 update 9 or later
and Oracle Linux 6 update 3 or later.
To upgrade an existing Oracle Linux 5 or Oracle Linux 6
installation to the latest UEK R2, enable the appropriate
UEK_latest channel and run yum update.
For detailed instructions on how to download and install the
Unbreakable Enterprise Kernel on Oracle Linux see the Getting
Started with the Unbreakable Enterprise Kernel for Oracle Linux
document on the Oracle Technology Network (OTN) at
http://www.oracle.com/technetwork/articles/servers-storage-admin/u
ek-rel2-getting-started-1555632.html.
If you have questions regarding configuring or using yum to
install updates, refer to the Oracle Linux Administrator's
Solutions Guide at http://docs.oracle.com/cd/E37670_01/index.html.
For information about using ULN, see the Oracle Linux Unbreakable
Linux Network User's Guide at
http://docs.oracle.com/cd/E37670_01/index.html.
The kernel's source code is available via a public git source code
repository at http://oss.oracle.com/git/?p=linux-uek-2.6.39.git.
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