Red Hat ENTERPRISE 5.4 RELEASE NOTES, Руководство пользователя

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Chapter 4. Known Issues
300
• The
QLogic iSCSI Expansion Card
for the
IBM Bladecenter
provides both ethernet and iSCSI
functions. Some parts on the card are shared by both functions. However, the current
qla3xxx
and
qla4xxx
drivers support ethernet and iSCSI functions individually. Both drivers do not support the
use of ethernet and iSCSI functions simultaneously.
Because of this limitation, successive resets (via consecutive
ifdown
/
ifup
commands) may hang
the device. To avoid this, allow a 10-second interval after an
ifup
before issuing an
ifdown
. Also,
allow the same 10-second interval after an
ifdown
before issuing an
ifup
. This interval allows
ample time to stabilize and re-initialize all functions when an
ifup
is issued.
(BZ#276891)
55
• Laptops equipped with the
Cisco Aironet MPI-350
wireless may hang trying to get a DHCP address
during any network-based installation using the wired ethernet port.
To work around this, use local media for your installation. Alternatively, you can disable the wireless
card in the laptop BIOS prior to installation (you can re-enable the wireless card after completing the
installation).
(BZ#213262)
56
• Hardware testing for the
Mellanox MT25204
has revealed that an internal error occurs under certain
high-load conditions. When the
ib_mthca
driver reports a catastrophic error on this hardware, it is
usually related to an insufficient completion queue depth relative to the number of outstanding work
requests generated by the user application.
Although the driver will reset the hardware and recover from such an event, all existing connections
at the time of the error will be lost. This generally results in a segmentation fault in the user
application. Further, if
opensm
is running at the time the error occurs, then you need to manually
restart it in order to resume proper operation.
(BZ#251934)
57
• If your system uses the TSC timer, the
gettimeofday
system call may move backwards. This is
because of an overflow issue that causes the TSC timer to jump forward significantly in some cases;
when this occurs, the TSC timer will correct itself, but will ultimately register a movement backwards
in time.
This issue is particularly critical for time-sensitive systems, such as those used for transaction
systems and databases. As such, if your system needs precision timing, Red Hat strongly
recommends that you set the kernel to use another timer (for example, HPET).
(BZ#443435)
58
• The
IBM T41
laptop model does not enter
Suspend Mode
properly; as such,
Suspend Mode
will
still consume battery life as normal. This is because Red Hat Enterprise Linux 5 does not yet include
the
radeonfb
module.
To work around this, add a script named
hal-system-power-suspend
to
/usr/share/hal/
scripts/
containing the following lines:
chvt 1
radeontool light off
radeontool dac off
This script will ensure that the
IBM T41
laptop enters
Suspend Mode
properly. To ensure that the
system resumes normal operations properly, add the script
restore-after-standby
to the
same directory as well, containing the following lines:
radeontool dac on