Cisco Cisco IOS Software Release 12.4(4)T 發佈版本通知

Further Problem Description: When an agentless host is authorized for network access, a dynamic 
access policy is applied for the host. This access policy is removed at the beginning of the 
reauthentication process, and re-applied at the end of reauthentication process. During the 
reauthentication process, no access policy is applied for the host. This situation may cause a 
disruption to network access. 

CSCse15025

Symptoms: An analog or digital CAS port enters a state in which inbound or outbound calls, or both, 
may no longer function through the port.

Conditions: This symptom is observed on a Cisco 2800 series and Cisco 3800 series that function 
as gateways with analog or digital CAS ports that use PVDM2 DSP modules.

When this problem occurs, it impacts multiple ports that share the same signaling DSP. The output 
of the show voice dsp signaling EXEC command shows which DSP is used by a port for signaling. 
The symptom may occur more often for ports that use DSP 1 on the PVDM2 module for signaling.

Because this issue impacts the signaling channels, it has been seen that calls either will not connect 
at all through impacted ports or in some cases when multiple simultaneous calls are present on 
adjacent voice ports/timeslots, the call may connect momentarily before being disconnected.

If a problem occurs only on a single voice port, there is another problem, not this caveat 
(CSCse15025). PRI/BRI calls are not affected because PRI/BRI does not utilize the DSP for 
signaling purposes.

When the symptom occurs with either a VIC2-xFXO or EVM DID/FXS module, enter the terminal 
monitor command followed by the test voice port port-numbersi-reg-read 39 1 comma nd for one 
of the affected ports. The output typically should be a single octet value for register 39. When the 
symptom occurs, information for Registers 40, 41, and 42 is presented and some of the registers 
show double-octet information. See the example output (2) below.

When the symptom occurs with FXS or analog E&M modules, enter the terminal monitor 
command followed by the test voice port port-number codec-debug 10 1 command for one of the 
affected ports. The output typically should be a single octet value for each register. See the example 
output (4) below.

Workaround: There is no workaround to prevent the symptom from occurring. When the symptom 
has occurred, you must reload the gateway to restore proper operation.

Further Problem Description: The changes in CSCse15025 includes changes in CSCsc11833 and 
CScsd90851. These changes have been shown to help mitigate this problem in the majority of cases.

There is a further detection and reset mechanism in CSCse15025 that will recover the DSP which is 
in this state. This mechanism will trigger immediately if the impacted voice port is an analog FXO 
port. For other voice ports, a delay in the detect ion will be present and it is possible to see the 
symptom of this problem before the recovery code triggers.

Note that the reset mechanism will cause any active calls utilizing the DSP in question to be 
dropped.

It is recommended if running with modules which can be impacted by this issue to upgrade to a 
release of software which contains the changes in CSCse15025. If the DSP is reset and the below 
output is seen, contact the TAC for further assistance. Note that this output is sent at debug level and 
it is recommended either to enable either syslog or logging buffered on the gateway.

Logging buffered on the gateway is enabled through the global command logging buffered 50000 
debug as an example to set the logging buffered to use 50K bytes of processor memory for logging. 
The output of the log can be seen wit h the exec command show log

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