User manual REDHAT ENTERPRISE LINUX 5.4 RELEASE NOTES

[. . . ] Red Hat Enterprise Linux 5. 4 Release Notes Release Notes for all architectures. This material may only be distributed subject to the terms and conditions set forth in the Open Publication License, V1. 0 or later (the latest version of the OPL is presently available at http://www. opencontent. org/openpub/). Red Hat and the Red Hat "Shadow Man" logo are registered trademarks of Red Hat, Inc. in the United States and other countries. [. . . ] Previously, CPU topology support was enabled by default. With this update, CPU topology support is disabled by default, and the kernel parameter "topology=on" has been added to allow this feature 46 to be enabled. (BZ#475797) · New kernel options can now be added using the IPL command without modifying the content of the CMS parmfile, allowing for temporary overwriting of kernel options that are already provided by the parmfile. The entire boot command line can be replaced with the VM parameter string, bypassing any kernel options from the parmfile. Furthermore, customers can create new Linux Named Saved 47 Systems (NSS) on the CP/CMS command line. (BZ#475530) · The qeth driver has been updated with HiperSockets Layer3 support for IPv6. (BZ#475572) For further details on this feature, refer to the "qeth device driver for OSA-Express (QDIO) and HiperSockets" chapter in IBM's "Device Drivers, Features, and Commands" book located at: http:// www. ibm. com/developerworks/linux/linux390/october2005_documentation. html · Starting with z9 HiperSocket firmware returns the version string in a different format. This change resulted in missing mcl_level information in the qeth status message issued during online setting 48 10 Kernel Updates of the device. The updated qeth driver now correctly reads the new version string format of 49 HiperSockets, allowing for a standardization of output format. (BZ#479881) · In Red Hat Enterprise Linux 5. 4, the s390utils package has been rebased to version 1. 8. 1. For a full list of features that this rebase provides, please refer to the Package Updates section of the 50 51 Technical Notes . (BZ#477189) · In the kernel, a sysfs interface has been implemented to associate actions to shutdown triggers. For more details on this feature, refer to the "Shutdown actions" chapter in IBM's "Device Drivers, Features, and Commands" book located at: http://www. ibm. com/developerworks/linux/linux390/ development_documentation. html 8. General Kernel Feature Support · Asymmetric Logical Unit Access (ALUA) support in device-mapper-multipath has been updated, adding explicit ALUA support for Clariion storage. Earlier versions of Red Hat Enterprise Linux 5 added support for implicit ALUA (i. e. the operating system is not aware of which storage device paths have optimized performance and which have non-optimized performance). If the operating system consistently sends I/O on a non-optimized path, then the storage device may transparently make that path optimized, improving performance and causing idle paths to become non-optimized. Red Hat Enterprise Linux 5. 4 introduces explicit ALUA support for Clariion storage (i. e. the operating system exchanges information with the storage device and is able to select the paths that have 52 optimized performance). (BZ#482737) · Previously, support for raw devices in the upstream kernel was deprecated. However, this support has been returned to the kernel. Consequently, in Red Hat Enterprise Linux 5. 4, support for raw devices has also been returned. [. . . ] This update fixes a bug in the driver that prevented adapter recovery if there were outstanding commands detected on the host 142 adapter. (BZ#497478 ) · This release includes the new qlge driver. This driver adds ethernet support for QLogic FCoE 10GB 143 adapters. Technology Previews Technology Preview features are currently not supported under Red Hat Enterprise Linux subscription services, may not be functionally complete, and are generally not suitable for production use. [. . . ]