Oracle(r) Linux
Release Notes for Unbreakable Enterprise Kernel Release 2 Quarterly
Update 4
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E41136-03
July 2013
Abstract
This document contains information on Quarterly Update 4 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: 2013-07-10 (revision: 1091)
_______________________________________________________
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
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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. It is based
on the mainline Linux 3.0 version 3.0.36. 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, which was
based on Linux 2.6.32.
The 2.6.39-400.109.1 release is the fourth 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
* The integrated OpenFabrics Alliance (OFED) 1.5.5 stack, which
supports the following InfiniBand hardware on systems with an
x86_64 architecture:
+ Mellanox ConnectX-2 InfiniBand Host Channel Adapters
+ Sun InfiniBand QDR Host Channel Adapter PCIe #375-3696
* The following kernel-level features are implemented for the
btrfs file system:
+ Allow metadata blocks to be larger than the page size (4
KB) and up to 64 KB in size.
+ A new ioctl call, BTRFS_IOC_DEVICES_READY, to read
device-readiness status.
+ Defragmentation does not undo sharing of data blocks
between snapshots. Previously, defragmentation could
result in more disk space usage because shared data
blocks were duplicated.
+ New ioctl calls, BTRFS_IOC_GET_LABEL and
BTRFS_IOC_SET_LABEL, to get or set a file system label.
+ Speed improvements for fsync direct I/O, and concurrent,
multithreaded reads.
+ Support for file-hole punching by calling fallocate()
with the FALLOC_FL_PUNCH_HOLE flag. Use the FIEMAP ioctl
to detect holes. The SEEK_HOLE and SEEK_DATA options to
the lseek() system call are not supported.
* The user-space btrfs-progs package (btrfs-progs-0.20-1.4) will
be provided on the ol6_latest channel for installation by
using yum update. Command-line access to the new features in
this package is not supported on kernel versions prior to this
update. If you install this update but not the updated
user-space btrfs-progs package, programmatic access is
possible for those features that present an ioctl or other
programming interface.
The updated btrfs-progs package supports the following
features in addition to the kernel-level features:
+ The -l option to mkfs.btrfs specifies the leaf size of a
file system. The default value of4k (4 KB) is recommended
for most uses. A value of 16k or 32k (16 or 32 KB) can
improve performance for some workloads by reducing
metadata fragmentation. The maximum supported size is 64k
(64 KB).
+ The btrfs filesystem label device newlabel command
supports labeling or relabeling of an existing file
system. The limitations are that the file system can only
have one device and you must first unmount the file
system. The btrfs filesystem show command displays a file
system's label.
+ Devices can be replaced at run time by using the btrfs
replace start command.
+ The btrfs filesystem balance command is able change btrfs
RAID profiles dynamically.
+ Collection of device statistics (numbers of read and
write failures, checksum errors, and corrupted blocks) by
using the btrfs device stats command.
+ Defragmentation can be cancelled by pressing Ctrl-C or by
killing the defragmentation process.
1.2. Xen Improvements
Several improvements have been incorporated into the Unbreakable
Enterprise Kernel to support Xen usage:
* Numerous bug fixes and performance improvements.
* Optimizations for xen/privcmd for ARM and PVH by a new
hypercall (add_to_physmap_range).
* Support for the balloon driver in Xen ARM.
* Enhancements to permit PVHVM backend drivers and allow dom0
functionality to be moved to guests.
* Implementation of the persistent grant extension to the block
ring protocol to improve block protocol scalability for large
numbers of physical cores and guests.
* Xen Processor Aggregator Device (PAD) added.
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
ATA over Ethernet
* ATA over Ethernet (AoE) driver (aoe) updated to 47q.
Broadcom
* NetXtreme II iSCSI driver (bnx2i) updated to 2.7.6.1d.
* NetXtreme II Fibre Channel over Ethernet driver (bnx2fc)
updated to 2.3.4.
Cisco
* Cisco FCoE HBA Driver (fnic) updated to 1.5.0.41.
Emulex
* Blade Engine 2 Open-iSCSI driver (be2iscsi) updated to
10.0.467.0o.
* Fibre Channel HBA driver (lpfc) updated to 0:8.3.7.10.4p.
LSI
* LSI Fusion-MPT base driver (mptbase) updated to 4.28.20.01.
* LSI Fusion-MPT ioctl driver (mptctl) updated to 4.28.20.01.
* LSI Fusion-MPT Fibre Channel host driver (mptfc) updated to
4.28.20.01.
* LSI Fusion-MPT IP Over Fibre Channel driver (mptlan) updated
to 4.28.20.01.
* LSI Fusion-MPT SAS driver (mptsas) updated to 4.28.20.01.
* LSI Fusion-MPT SCSI host driver (mptscsih) updated to
4.28.20.01.
* LSI Fusion-MPT SPI host driver (mptspi) updated to 4.28.20.01.
* LSI Fusion-MPT SAS 2.0 driver (mpt2sas) updated to
16.05.01.00.
MegaRAID
* MegaRAID SAS driver (megaraid_sas) updated to 06.505.02.00.
Mellanox
Note
These drivers were first released in UEK R2 Quarterly Update 3.
* ConnectX core driver (mlx4_core) released at 1.0-ofed1.5.5
(x86_64 only). Handles low-level functions such as device
initialization and firmware commands processing, and controls
resource allocation so that the InfiniBand and Ethernet
functions can share a device without interfering with each
other.
* ConnectX Ethernet driver (mlx4_en) updated to 1.5.10 (Jan
2013) (x86_64 only). Handles Ethernet-specific functions and
plugs into the netdev mid-layer.
* ConnectX InfiniBand driver (mlx4_ib) released at 1.0-ofed1.5.5
(x86_64 only). Handles InfiniBand-specific functions.
QLogic
* Fibre Channel HBA driver (qla2xxx) updated to
8.05.00.03.39.0-k.
* iSCSI driver (qla4xxx) updated to 5.03.00.02.06.02-uek2.
Supports Open-iSCSI.
1.3.2. Network Adapter Drivers
Broadcom
* NetXtreme II network adapter driver (bnx2) updated to 2.2.3n.
* NetXtreme II 10Gbps network adapter driver (bnx2x) updated to
1.76.54.
* Converged Network Interface Card core driver (cnic) updated to
2.5.16g.
* Tigon3 Ethernet adapter driver (tg3) updated to 3.129d.
Emulex
* Blade Engine 2 10Gbps adapter driver (be2net) updated to
4.6.62.0u.
Intel
* PRO/1000 PCI-Express Gigabit network adapter driver (e1000e)
updated to 2.3.2-NAPI.
* Gigabit Ethernet network adapter driver (igb) updated to
4.1.2.
* 10 Gigabit PCI-Express network adapter driver (ixgbe) updated
to 3.14.5.
* 10 Gigabit Server Adapter virtual function driver (ixgbevf)
updated to 2.8.7. The kernel must support Single Root I/O
Virtualization (SR-IOV).
QLogic
* 1/10 GbE Converged/Intelligent Ethernet Adapter driver
(qlcnic) updated to 5.2.29.45.
* QLE81xx network adapter driver (qlge) updated to v1.00.00.32.
Realtek PCI Express Gigabit Ethernet controller
* Realtek PCI Express Gigabit Ethernet controller (r8169)
updated to 2.3LK-NAPI.
VMware
* VMware VMXNET3 virtual ethernet driver (vmxnet3) updated to
1.1.30.0-k.
1.3.3. Miscellaneous Drivers
HP
* HP ProLiant Channel Interface Device Driver for iLO (hpilo)
updated to 1.4.
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.
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
The following issues have been fixed in this update.
* A kernel panic could occur during path failover if one of the
paths to a multipathed SCSI device was disabled. (Bug ID
16684527)
* Several fixes have been applied to correct race conditions
within cgroup movement of newly created, forking, and waking
processes. (Bug ID 13740515)
* Several fixes have been applied to the OVM API.
* A fix has been applied to prevent a kernel panic that could
occur when moving OCFS2 extents during defragmentation. (Bug
ID 16631951)
* The updated btrfs-progs package (btrfs-progs-0.20-1.4), which
will be provided on the ol6_latest channel, fixes a bug where
the btrfs subvolume get-default command listed all existing
subvolumes instead of only the default subvolume. (Bug ID
13815433)
* Security fixes for several CVEs, including CVE-2013-2094.
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 this quarterly update, a
new version of the user-space btrfs-progs package
(btrfs-progs-0.20-1.4) will be provided on the ol6_latest
channel. This package enables command-line access to new btrfs
features. If you install this latest version 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 fsync 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.
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)
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)
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.
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)
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 and 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 4 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)
Chapter 3. Installation and Availability
The Unbreakable Enterprise Kernel Release 2 Quarterly Update 4 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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