Cisco Cisco IOS Software Release 12.4(23)
785
Caveats for Cisco IOS Release 12.4
OL-7656-15 Rev. J0
Resolved Caveats—Cisco IOS Release 12.4(3g)
Conditions: This can occur when excessive jitter is present on the IP network side impacting the
incoming RTP stream to the IOS VoIP gateway. This is present only when using MGCP controlled
voice ports and Cisco IOS 12.3.14T and higher.
incoming RTP stream to the IOS VoIP gateway. This is present only when using MGCP controlled
voice ports and Cisco IOS 12.3.14T and higher.
The issue stems from the jitter buffer playout mode for that call being set to a fixed mode of 65msec
versus adaptive mode.
versus adaptive mode.
The typical symptom would be that voice quality may degrade for calls where excessive jitter is
present in the RTP stream.
present in the RTP stream.
This issue can be confirmed by checking the output of the exec command show call act voice for an
active call experiencing voice quality problems. This problem can be seen when the late packets
count is increasing but the PlayoutDelayCurrent as well as the PlayoutDelayMax is fixed at 65msec.
See snippet of this command output below:
active call experiencing voice quality problems. This problem can be seen when the late packets
count is increasing but the PlayoutDelayCurrent as well as the PlayoutDelayMax is fixed at 65msec.
See snippet of this command output below:
-----
RxLatePak=23
RxEarlyPak=0
PlayDelayCurrent=65
PlayDelayMin=65
PlayDelayMax=65
----
Workaround: Use H323 instead of MGCP or use Cisco IOS Release 12.3(11)T.
•
CSCsd35389
Symptoms: When a Cisco Unified CallManager Express (Cisco Unified CME) registers with a
gatekeeper, all the ephone-dns are automatically registered. When an ephone-dn is deleted, it does
not unregister with the gatekeeper. If you enter the no gateway command followed by the gateway
command on the CME router to force it to unregister then reregister, the deleted ephone-dn will
show up again.
gatekeeper, all the ephone-dns are automatically registered. When an ephone-dn is deleted, it does
not unregister with the gatekeeper. If you enter the no gateway command followed by the gateway
command on the CME router to force it to unregister then reregister, the deleted ephone-dn will
show up again.
Conditions: This symptom is observed on a Cisco 3800 series router.
Workaround: To permanently remove the ephone-dn reload the CME/gateway or enter the shut
command followed by the no shut command on the gatekeeper.
command followed by the no shut command on the gatekeeper.
•
CSCsd76444
Symptoms: A Cisco router may reload unexpectedly with a “Signal 0” without a stack trace in the
crash info file.
crash info file.
Conditions: This symptom is observed on a Cisco 10000 series that has a PRE and that is configured
for SSG. However, the symptom is platform-independent and may occur on any router that is
configured for SSG.
for SSG. However, the symptom is platform-independent and may occur on any router that is
configured for SSG.
Workaround: There is no workaround.
•
CSCse03855
Symptoms: An IP phone display remains stuck at “Enter Number” for the duration of an outgoing
call to the PSTN.
call to the PSTN.
Conditions: This symptom is observed when the IP phone runs CME version 3.3 and is connected
to a BRI ISDN interface on a Cisco router that runs Cisco IOS Release 12.4. When you enable the
debug isdn q931 command, the following message is displayed in response to an outgoing setup
message:
to a BRI ISDN interface on a Cisco router that runs Cisco IOS Release 12.4. When you enable the
debug isdn q931 command, the following message is displayed in response to an outgoing setup
message:
ISDN BR0/2/0 Q931: RX <- SETUP_ACK pd = 8 callref = 0x83
Channel ID i = 0x89
Progress Ind i = 0x8288 - In-band info or appropriate now available