Cisco Cisco 2106 Wireless LAN Controller 發佈版本通知
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Release Notes for Cisco Wireless LAN Controllers and Lightweight Access Points for Release 5.1.163.0
OL-31336-01
Important Notes
Crash Files for 1250 Series Access Points
The 1250 series access points may contain either an old bootloader or a new bootloader. Those with an
old bootloader do not generate a crash log when a crash occurs. The crash log is disabled so that a crash
does not corrupt the flash file system. Those with a new bootloader generate a crash log if the access
point is running controller software release 4.2.112.0 or later.
old bootloader do not generate a crash log when a crash occurs. The crash log is disabled so that a crash
does not corrupt the flash file system. Those with a new bootloader generate a crash log if the access
point is running controller software release 4.2.112.0 or later.
New 1250 series access points shipped from the factory contain the new bootloader image, which fixes
the flash file system after it is corrupted during a crash (without losing files). This new bootloader
automatically sets a new CRASH_LOG environment variable to “yes,” which enables a crash log to be
generated following a crash but only on controllers running software release 4.2.112.0 or later.
Therefore, no user configuration is needed to enable a crash log on new 1250 series access points shipped
from the factory.
the flash file system after it is corrupted during a crash (without losing files). This new bootloader
automatically sets a new CRASH_LOG environment variable to “yes,” which enables a crash log to be
generated following a crash but only on controllers running software release 4.2.112.0 or later.
Therefore, no user configuration is needed to enable a crash log on new 1250 series access points shipped
from the factory.
Configuration File Stored in XML
In controller software release 4.2.61.0 and later, the controller’s bootup configuration file is stored in an
Extensible Markup Language (XML) format rather than in binary format. When you upgrade a controller
to 4.2.61.0 or a later software release, the binary configuration file is migrated and converted to XML.
Extensible Markup Language (XML) format rather than in binary format. When you upgrade a controller
to 4.2.61.0 or a later software release, the binary configuration file is migrated and converted to XML.
Note
You cannot download a binary configuration file onto a controller running software release 5.1.163.0.
Also, do not attempt to make changes to the configuration file. If you do so and then download the file
to a controller, the controller displays a cyclic redundancy checksum (CRC) error while it is rebooting
and returns the configuration parameters to their default values.
Also, do not attempt to make changes to the configuration file. If you do so and then download the file
to a controller, the controller displays a cyclic redundancy checksum (CRC) error while it is rebooting
and returns the configuration parameters to their default values.
LWAPP Mode Changes
When you upgrade to controller software release 5.0.148.0 or later, the LWAPP mode changes to Layer
3 if it was previously configured for Layer 2.
3 if it was previously configured for Layer 2.
If you downgrade from controller software release 5.1.163.0 or 5.0.148.0 to 4.2.61.0 or an earlier release,
the LWAPP mode changes from Layer 3 to Layer 2. Access points may not join the controller, and you
must manually reset the controller to Layer 3 to resolve this issue.
the LWAPP mode changes from Layer 3 to Layer 2. Access points may not join the controller, and you
must manually reset the controller to Layer 3 to resolve this issue.
Access Points Send Multicast and Management Frames at Highest Basic Rate
Access points running recent Cisco IOS versions transmit multicast and management frames at the
highest configured basic rate, which could cause reliability problems. Access points running LWAPP or
autonomous IOS should transmit multicast and management frames at the lowest configured basic rate.
Such behavior is necessary to provide good coverage at the cell’s edge, especially for unacknowledged
multicast transmissions where multicast wireless transmissions may fail to be received.
highest configured basic rate, which could cause reliability problems. Access points running LWAPP or
autonomous IOS should transmit multicast and management frames at the lowest configured basic rate.
Such behavior is necessary to provide good coverage at the cell’s edge, especially for unacknowledged
multicast transmissions where multicast wireless transmissions may fail to be received.
Because multicast frames are not retransmitted at the MAC layer, clients at the edge of the cell may fail
to receive them successfully. If reliable reception is a goal, then multicast frames should be transmitted
at a low data rate. If support for high data rate multicast frames is required, then it may be useful to shrink
the cell size and disable all lower data rates.
to receive them successfully. If reliable reception is a goal, then multicast frames should be transmitted
at a low data rate. If support for high data rate multicast frames is required, then it may be useful to shrink
the cell size and disable all lower data rates.