Red Hat ENTERPRISE 5.4 RELEASE NOTES, Manual

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by other packages and administrators. The "pkiuser" user and group IDs are used in subsystems
associated with the Red Hat Certificate System.
• this updated setup package reserves the new "vdsm" user ID and "kvm" group ID, and the userid
(UID) and groupid (GID) numbers (36:36), which should prevent accidental usage of that UID/GID
pair by other packages and administrators. VDSM service manages a single SolidICE node (VDS).
It serves as a proxy for Virtual Machine creation, management, statistics, and log collection.
• this updated setup package reserves the new "oprofile" user ID and group ID, and the userid (UID)
and groupid (GID) numbers (16:16), which should prevent accidental usage of that UID/GID pair
by other packages and administrators. The "oprofile" user and group IDs are used by the OProfile
program, a low-overhead, system-wide profiler capable of running transparently in the background.
Users are advised to upgrade to this updated setup package, which resolves these issues and adds
these enhancements.
1.207. sg3_utils
1.207.1. RHBA-2009:1357: bug fix and enhancement update
Updated sg3_utils packages that fix several bugs and add an enhancement are now available.
The sg3_utils package contains a collection of tools for SCSI devices that use the Linux SCSI generic
(sg) interface. It includes utilities to copy data based on "dd" syntax and semantics (the sg_dd, sgp_dd
and sgm_dd commands), check INQUIRY data and associated pages (sg_inq), check mode and
log pages (sg_modes and sg_logs), spin disks up and/or down (sg_start) and perform self-tests
(sg_senddiag), along well as various other utilities.
These updated sg3_utils packages provide the following enhancement:
• for Red Hat Enterprise Linux 5.4 a new shell script, "rescan-scsi-bus.sh", has been added to the
sg3_utils package. This script utilizes the capabilities of the Linux kernel to add and remove SCSI
devices without the need to reboot the machine or reload a kernel module. (
BZ#507379
1597
)
This script should be considered a Technology Preview for Red Hat Enterprise Linux 5.4.
Warning
the rescan-scsi-bus.sh script can remove storage devices from the system as well as add
them. Before issuing any command that may cause device removal from the operating
system, close all users of the device; unmount any file systems mounting the device;
and remove the device from any dm, md, LVM, multipath or RAID setups using it. If you
intend, therefore, to add or remove devices from a bus while i/o is on-going, perform these
operations on one device at a time and check the results as each step is completed. Do
not perform a scan that adds and removes devices at the same time. See the
Online
Storage Reconfiguration Guide
1598
for a complete overview of this topic. (
BZ#467201
1599
)
Note
"sd" device names are not persistent and may change when devices are removed or
added. Use WWIDs or disk metadata to reliably identify devices.