Symptom:Intermittently, an access point may fail to transmit data frames out its radio interface.
With client tracing enabled on the AP, the AP indicates that it thinks that it is transmitting;
however, an over-the-air packet capture does not see these frames.
For example, DNS may fail - with the AP showing that it thinks it it sending the DNS REPLY packets out the radio:
Jul 3 02:11:35 kernel: [*07/03/2020 02:11:35.9609] [1593742295:960956] [AP3C51.0E40.AAEE] [9c:da:3e:91:ba:db] [D:W] DNS REPLY : id 31337 opcode 0
But this packet is not seen in the OTA sniff, and is not received by the client.
Similar failures are seen with downstream DHCP OFFER, ARP response, etc. packets being dropped by the AP radio.
Conditions:Seen with an AP of one of the following models: 2800/
3800/4800/1560/6300. This bug does not apply to any other AP model.
This problem is most
often seen with MU-MIMO enabled,
but can also be seen with MU-MIMO disabled.
Workaround:* Temporary workaround: reboot the AP.Disabling MU-MIMO may reduce the frequency with which this problem is seen.
Further Problem Description:CSCvt22353 was believed to have fixed MU-MIMO-caused transmission stalls, but problems persist
in AP code with the
CSCvt22353 fix.
This bug
CSCvv78719 does not fix the root cause of the problem, but implements a workaround: once
the AP detects that the radio transmission have stalled, it will reset the radio, restoring communications.
With this
CSCvv78719 workaround, intermittent transmission stalls of 20 seconds or so may be experienced.
If you have the
CSCvv78719 workaround in place, and are experiencing intermittent stalls and would like
to assist Cisco in determining the root cause of the bug, please open a TAC case and work with TAC ...
you will be asked to configure "show dot11 generic wlcfg wifi0/1 TcqStuckDebug 1" on the APs that
exhibit the problem, in order to collect further diagnostic information.
Resolved Caveats
Table 13.
Resolved CaveatsCaveat ID NumberDescription
CSCvv78719 | AP2800/3800/4800/1560/6300 fails to transmit data frame to the client from the radio interface |
但是该版本不支持AP3602了，仅支持如下AP
The following Cisco AP platforms are supported in this release:
Cisco Catalyst 9105 Access Points
Cisco Catalyst 9130 Access Points
Cisco Catalyst 9120 Access Points
Cisco Catalyst 9117 Access Points
Cisco Catalyst 9115 Access Points
Cisco Aironet 700 Series Access Points
Cisco Aironet 700W Series Access Points
Cisco AP803 Integrated Access Point
Integrated Access Point on Cisco 1100, 1101, and 1109 Integrated Services Routers
Cisco Aironet 1700 Series Access Points
Cisco Aironet 1800 Series Access Points
Cisco Aironet 1810 Series OfficeExtend Access Points
Cisco Aironet 1810W Series Access Points
Cisco Aironet 1815 Series Access Points
Cisco Aironet 1830 Series Access Points
Cisco Aironet 1840 Series Access Points
Cisco Aironet 1850 Series Access Points
Cisco Aironet 2700 Series Access Points
Cisco Aironet 2800 Series Access Points
Cisco Aironet 3700 Series Access Points
Cisco Aironet 3800 Series Access Points
Cisco Aironet 4800 Series Access Points
Cisco ASA 5506W-AP702
Cisco Aironet 1530 Series Access Points
Cisco Aironet 1540 Series Access Points
Cisco Aironet 1560 Series Access Points
Cisco Aironet 1570 Series Access Points
Cisco Industrial Wireless 3700 Series Access Points
Cisco Catalyst IW6300 Heavy Duty Series Access Points
Cisco 6300 Series Embedded Services Access Points
