Cisco Cisco Aironet 1310 Access Point Bridge 릴리즈 노트
22
Release Notes for Cisco Aironet Access Points and Bridges for Cisco IOS Release 12.4(21a)JA1
OL-20668-01
Caveats
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STA/CB72---------Cisco AP1252--------Radius Server
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CSCsz16427—Image recovery process hangs on hard reset.
The bootable image in flash is not getting erased and the image recovery process hangs after
pressing the reset button for more than 20 seconds.
pressing the reset button for more than 20 seconds.
Workaround: Erase the image in flash manually and then hard reset the access point, or increase the
tftpserver timeout value from the default setting.
tftpserver timeout value from the default setting.
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CSCtc06925—A 1250 workgroup bridge fails to scan for the uplink when it goes out of A WiFi
zone.
zone.
The workgroup bridge fails to scan for the uplink when it goes out of a WiFi zone for more than 30
minutes. When it returns to the WiFi zone the workgroup bridge never gets the uplink, unless the
interface is cleared.
minutes. When it returns to the WiFi zone the workgroup bridge never gets the uplink, unless the
interface is cleared.
Workaround: Clear the workgroup bridge interface causes it to associate again.
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CSCtc07598—7921 phone disconnects in random fashion and “CM down -feature disable” message
is displayed.
is displayed.
Two 7921 VOIP phones connected to a 1250 or 1130 access point begin a conversation. The call
works fine for 45 - 60 minutes but then the call drops and the following message in one of the 7921
phones displays “CM down.feature disable” (receiver phone mostly). After ending the call, the 7921
phone keeps trying to connect the CM IP address, then the phone reassociates with the access point
and repeats the cycle.
works fine for 45 - 60 minutes but then the call drops and the following message in one of the 7921
phones displays “CM down.feature disable” (receiver phone mostly). After ending the call, the 7921
phone keeps trying to connect the CM IP address, then the phone reassociates with the access point
and repeats the cycle.
•
CSCtc09255—1140 access point in repeater mode exhibits traceback/crash for WPA-optional.
Workaround: Shut the interface before changing the security configuration.
•
CSCtc15346—AP1252 fails to retransmit missing AMPDU packet in response to block ack
When a wireless 802.11n client is receiving bulk data—for example, downloading a large file—the
transmissions may stall. Pings and other IP connectivity to that client at that time will fail.
transmissions may stall. Pings and other IP connectivity to that client at that time will fail.
Workaround:
1. Disable 802.11n on the AP and/or client.
2. Disable block ack (AMPDU) on the AP and/or client. If the AP is running under WLC control,
then use the following commands:
then use the following commands:
config 802.11b 11nsupport a-mpdu tx priority all disable
config 802.11a 11nsupport a-mpdu tx priority all disable
If the AP is running aIOS, then use this command:
no ampdu transmit priority 0
This will cause the AP to transmit bulk data using AMSDU rather than AMPDU, and so may result
in a 10-15% throughput reduction.
in a 10-15% throughput reduction.
Further Problem Description:
At the time when the transmission stalls, a wireless packet capture will show this sequence of events:
The AP1252 transmits an AMPDU packet train. One of the packets in the middle of the train is
errored. Client sends a block-ack indicating that the errored packet needs to be retransmitted, but
the AP fails to retransmit. Therefore the transmission stalls.
The AP1252 transmits an AMPDU packet train. One of the packets in the middle of the train is
errored. Client sends a block-ack indicating that the errored packet needs to be retransmitted, but
the AP fails to retransmit. Therefore the transmission stalls.