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Cisco Voice Switch Service Module (VXSM) Configuration Guide, Release 5.2
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PDF Version of Cisco Voice Switch Service Module (VXSM) Configuration Guide, Release 5.2
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About this Guide
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Introduction
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General Description
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Configuration for VoIP Switching Applications
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Configuration for AAL2 Trunking Applications
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Configuring VXSM Features
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Loading and Upgrading VXSM Code Images
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VXSM Troubleshooting
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Media Gateway Clocking
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Table Of Contents
Collecting Trouble Shooting Data
Getting Information on Current Voice Calls (H.248)
Getting Information on Current Voice Calls (xGCP)
Bearer Tracing Troubleshooting Tool
Other Considerations and Limitations
Configuring the Bearer Tracing Feature
Examples of a Bearer Trace Configuration
Troubleshooting a Bearer Trace Operation
Summary of Bearer Trace Commands
Other Useful Trouble Shooting Commands
VXSM Trouble Shooting
This chapter describes how to trouble shoot and resolve known types of problems on the Cisco MGX 8850 VXSM card. The following topics are covered in this chapter:
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Collecting Trouble Shooting Data
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Collecting Trouble Shooting Data
This section provides procedures for collecting trouble shooting data for when a VXSM card fails. These procedures use PXM45, VXSM, RPM-XF and AXSM commands. See Chapter 5, "VXSM CLI Commands" in this document for detailed descriptions of the VXSM CLI commands. Refer to the following documents for descriptions of the PXM45, RPM-XF and AXSM CLI commands:
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•
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Table 7-1 shows the initial steps you can take using CLI commands to trouble shoot any problem on the VXSM. These steps enable you to collect data and failure reports.
Trouble Shooting Procedures
Table 7-2 provides a list of known types of problems, their possible causes, and their possible solutions. The problems are listed alphabetically by topic.
Getting Information on Current Voice Calls (H.248)
With H.248, calls are modeled using a "context". A context contains one or more "terminations". In Release 5, a context can contain at most two terminations.In this release, there are two types of terminations: TDM (also referred to as SCN or Switched Circuit Network); and RTP.
A basic VoIP call "leg" is modeled as a context containing one TDM termination and one RTP termination.
Figure 7-1 VoIP Call Leg Model
.
A TDM hairpin call is modeled as a context containing two TDM terminations.
Figure 7-2 TDM Hairpin Model
Table 7-3 shows the commands used to get information about the current voice calls on the VXSM.
Examples
The dsph248calls CLI command displays all of the H.248 terminations,
shelf.1.VXSM.a > dsph248calls
TermId TermType Media Codec Vad Ecan
------ -------- -------- ----- ----- ----
1 SCN 'Voice' 'G.711 U' ----- 'Enabled'
8067 RTP 'Voice' 'G.711 U' 'Enabled' -----
2 SCN 'Voice' 'G.711 U' ----- 'Enabled'
8068 RTP 'Voice' 'G.711 U' 'Enabled' -----
The dsph248status -cntxs CLI command displays the status of all H.248 contexts,
shelf.1.VXSM.a > dsph248status -cntxs
=======================================
Status for all contexts
=======================================
Number of active contexts:2
List of contexts
Status of context 4:
Creation date and time:02/03/2004, 17:31:21
Number of terminations in context:2
List of termination IDs:
8068 2
Status of context 3:
Creation date and time:02/03/2004, 17:31:21
Number of terminations in context:2
List of termination IDs:
8067 1
The dsph248status -cntx CLI command displays the status of a particular H.248 context,
shelf.1.VXSM.a > dsph248status -cntx 1
=======================================
Status of context 1
=======================================
Creation date and time: 07/04/2003, 13:55:45
Number of terminations in context: 2
List of terminations:
term_id: 8065, term_type: MG_TERM_TYPE_PDN_IP, term_name: RTP8065
term_id: 3, term_type: MG_TERM_TYPE_SCN, term_name: ds/1/1/3
The dsph248status -term CLI command displays the status of a particular H.248 termination,
shelf.1.VXSM.a > dsph248status -term 1 1 1
==========================================
Status of termination with ID 1
==========================================
Termination type:MG_TERM_TYPE_SCN
Termination name:ds/1/1/1
Termination state:MG_TERM_STATE_INSERVICE
Termination test flag:False
Termination context id:3
Id of profile on termination:0
Number of streams on termination:1
Termination about to be deleted:False
Next state of termination:MG_NEXT_STATE_INSERVICE
Last modified/updated:02/03/2004, 17:31:21
NOTE:This timestamp is not preserved across switchovers.
It is independently generated on each card.
Supported packages:
H248_GENERIC_PKG H248_TDMC_PKG
The dsph248call -term CLI command displays information pertaining to a particular H.248 termination,
shelf.1.VXSM.a > dsph248call -term 1
Term Id :1
Term Type :SCN
Term Name :ds/1/1/1
connMode :4 ('Send-recv')
loopBackType :1 ('None')
RTP Encapsulation Parameters ...
ssrc :424285698 (0x194a1602)
RTCP Enable :TRUE
dspCodec :2 ('G.711 U')
packetPeriod :'20 ms'
vadMode :2 ('Enabled')
vadThreshold :-38
vadHangoverTime :250 ms
ecan enabled :'Enabled'
ecanTail :128 ms
ecanFlags :0x0
Type <CR> to continue, Q<CR> to stop:
upspeedCodec :2 ('G.711 U')
jitterMode :2 ('Adaptive')
jitterMinDelay :5 ms
jitterMaxDelay :100 ms
jitterNomDelay :30 ms
jitterFaxNomDelay :0 ms
txGain :0
rxGain :0
nsePayloadType :100 (0x64)
nteTxPayloadType :0 (0x0)
nteRxPayloadType :0 (0x0)
profileType :0
profileNum :0
hsRedCount :0
lsRedCount :0
toneDetect :0x3c32
toneDetectBitmap :0x0
Type <CR> to continue, Q<CR> to stop:
digitDetect :1 ('DTMF')
digitRelayMethod :1 ('Send as Voice')
icsEnable :0 (FALSE)
nx64FramePattern :0 (CRML_PATTERN_NONE)
trunkMode :0 (CRML_MODE_NONE)
nx64FrameFlagCnt :0
dtmfTransport :0 (FALSE)
trunkCond :0 (FALSE)
The dsph248cnts -phyterm CLI command displays counters corresponding to all of the H.248 physical (TDM/SCN) terminations on the VXSM card,
shelf.1.VXSM.a > dsph248cnts -phyterm
=================================================================
All Gateway Physical Terminations Statistic
DS1:DS0 Termination Termination Num of Num of Num of OOS Num of OOS
line Id Name Add Failure from MGC from OAM
============ =========== ============ ====== ======= ==========
1.1.1.2.3:1 361 DS/1/16/1 1 0 0 0
1.1.1.2.3:2 362 DS/1/16/2 0 0 0 0
......
1.1.1.2.3:23 383 DS/1/16/23 0 0 0 0
1.1.1.2.3:24 384 DS/1/16/24 1 0 0 0
The dsph248cnt -ephterm CLI command displays counters corresponding to all of the H.248 ephemeral (RTP, ...) terminations on the VXSM card,
shelf.1.VXSM.a > dsph248cnt -ephterm
=========================================================
Gateway Ephemeral Terminations Statistic
=========================================================
Num of Add Commands : 2
Num of Commands Failure : 0
Getting Information on Current Voice Calls (xGCP)
The xGCP call model is based upon endpoints and connections. Connections have modes. Supported modes include Receive-Only, Send/Receive, Inactive, Loopback, and Continuity Test. The connection model is shown in Figure 7-3.
Figure 7-3 xGCP Connection Model
To obtain information regarding the status of TGCP activities. use the PXM and VXSM commands as follows/
The following PXM CLI commands will display the list of events and errors logged by the active and standby VXSM cards, starting with the most recent event or error.
The following VXSM CLI commands are useful to monitor the basic operation of the currently active VXSM card and to check if calls are being processed after switchover:
dspxgcpcnts - displays a static summary of the number of TGCP commands that failed/succeeded on the ACTV card at that moment; executing this command a few times will give the user an idea whether commands are being sent to the VXSM and whether VXSM is processing those commands
dspxgcpdetailcnts - displays number of times a particular TGCP command is received/sent/retransmitted
dspxgcpendpts <endpt-name> - displays all the endpt state, if connection is present on that endpoint.
`dspxgcpendpts *' can be used to display all
-dspxgcpendptcons <endpt-name> - displays the connection id, call id of the connection on that endpoint
Bearer Tracing Troubleshooting Tool
Introduction
The VXSM card includes a useful troubleshooting tool that has the ability to collect fundamental information about the content of bearer streams and to transmit the information in real-time to an external file server for offline analysis. This feature, known as Bearer Tracing, involves the VXSM card, the Media Gateway Controller for VoIP applications, and a file server to receive the bearer traces (see Figure 7-4).
Figure 7-4 Bearer Tracing Major Elements
Within the VXSM card, the Bearer Tracing feature is performed in the Voice Module as shown in Figure 7-5.
Figure 7-5 VXSM Bearer Tracing High Level Functional Blocks
The Voice Module contains a number of probes on the card that are situated at various points in the path of the bearer stream through the card.
There are eight such probes situated as shown in Figure 7-6.
Figure 7-6 Bearer Trace Probe Locations
Note
The probes are:
1 = PCM Input from TDM network
2 = PCM Output to the TDM network.
3 = Input from the packet network (not operational in VXSM Release 5.2)
4 = Output to the packet network (not operational in VXSM Release 5.2)
5 = Output from echo canceller (Ecan/Sout)
6 = Voice Playout Unit - Jitter buffer
7 = T.38 information at the Decoder - level 1
Bearer Trace Operation
Step 1
a.
In VOIP: A call needs to be setup
orIn AAL2, an AAL2 nailed up connection needs to be added by adding a CID
And
b.
Note
Step 2
a.
b.
Step 3
a.
b.
Note
Step 4
Note
If the connection to the file server can't be established, bearer tracing will be deactivated and the VXSM card may not function correctly. To reactivate bearer tracing, fix the network issues that are preventing the network connection to be established.
Step 5
Step 6
Step 7
Note
b. If the network connection experiences problems while bearer tracing is writing trace data into the trace file, bearer tracing may be deactivated and the VXSM card may not function correctly. To reactivate bearer tracing, fix the network issues that are preventing the network connection to be established
Bearer Trace Types
Bearer Traces are transmitted to the server as files with file names that indicate the probe type, the endpoint being probed and, optionally, a timestamp. Files are assigned names by the Bearer Tracing feature that indicate these items. For more details on file naming see Trace Files.
PCM Traces
There are 2 PCM traces, pcmin and pcmout, to and from the voice network, respectively. In CLI, pcmin Probe 1 collects pcmin and probe 2 collects pcmout. The pcmin trace files generated by VXSM have the pcmin prefix and.pcm suffix, pcmout trace file have the pcmout prefix and the .pcm suffix.
The format for a PCM trace is either 8-bit PCM A-law or 8-bit PCM mu-law, depending on the physical interface being used. VXSM currently ties the PCM encoding to the physical interface.
Echo Canceller (Sout) Traces
The Sout trace is collected from the "output" of the echo canceller and is collected by probe 5.
The format of the Sout stream is a big-endian signed 16-bit linear format. The value 32757 represents full scale. The sout trace file generated by VXSM has the sout prefix and .pcm suffix
The Sout stream is synchronized to the PCM In and PCM Out signals.
The Sout tracing cannot be enabled if the Ecan is not enabled on the given connection
Packet Traces
The packet traces are collected at the input and output of the Packet IO interface.
The current implementation focuses on RTP traces. The packet trace is in raw IP pcap format that is readable by packet sniffers such as Ethereal.
VPU Traces
The VPU trace is on Probe 6. When a VPU segment trace is started, an event trace is started automatically.
The Voice Playout Unit (Jitter Buffer) Segment trace (vpseg) reports jitter-related data every segment, that is every 5ms.
The VPU Event trace (vpevt) reports jitter-related events when they happen.
Each type of VPU trace produces it own trace file. Segment files have the suffix .seg and Event files have the suffix .evt.
T.38 Traces
When a fax call is active using T.38 fax relay, traces can be gathered from the Fax module within the DSP. The user can select to gather 2 levels of traces:
Level 1 - basic events to decipher T.30 and other signaling progress
Level 2 - proprietary format
When enabling the tracing functionality for T.38 it is possible to enable tracing for an entire DS1 or a specific DS0. When monitoring a DS1 the first fax relay session activated on the monitored span will have tracing enabled. Enabling a trace for an entire DS1 is specified by a special probe in the addbearertraceendpt command.
A total of 10 simultaneous DS1 spans can be monitored at any one time. In addition to this a maximum number of 10 trace sessions can be obtained simultaneously.
Bearer Tracing Connectivity
External Interface
VXSM can be connected to the file server either through the Control PVC or through the VXSM Ethernet port.
If the control PVC is used, the provisioning of the control PCV needs to include the bandwidth required for the transfer of trace data to the network.
Per Trace Bandwidth and File Size Requirements
Bearer tracing requires that enough bandwidth be available to accommodate the bearer trace traffic data and the transport protocol packet and control overhead. Table 7-6 and Table 7-7 below show the estimate per-trace bandwidth requirements in the case of ftp and tftp. The file size of the accumulated bearer trace data on the server is also provided so that enough space is set aside for the trace files to be stored in the ftp server. The file size of the trace files is limited only by the free space on the file server. To make sure that trace files have no loss of data, provide enough space on the file server for the trace files.
Bearer Tracing for AAL2 connections
FTP and TFTP protocols run on an IP network. For Voice over IP, VXSM inherently uses an AAL5 control PVC to communicate with the MGC. The same control PVC can be used to communicate with the external FTP/TFTP server.
Control PVC isn't inherent in an AAL2 configuration (example: AAL2 trunking). To access the IP cloud in such a situation, either a control PVC or the Ethernet console need to be configured. Unless pinging the file server is possible, tracing will not operate.
IPSec and Bearer Tracing
The Bearer Tracing mechanism uses FTP/TFTP connections to transfer the traces to the server. The trace data are carried over the control PVC, which is also used to communicate with MGC. For many solutions, IPSec is used to secure the communication with the MGC over control PVC. In such cases, the FTP/TFTP traffic is bypassed by IPSec in order to transfer trace data to the bearer tracing server.
Bearer Trace CLI Requirements
Persistency
The operational state of bearer tracing is not saved in disk database. Hence, all the information is lost if the card resets. All the bearer tracing commands are non-MIB commands.
Backward Compatibility
Commands introduced in the PCM tracing functionality in the earlier VXSM releases are no longer functional. They are replaced by the new bearer tracing commands in VXSM Release 5.3.
Bearer Trace Configuration
Once a bearer trace or a server profile is added, the only way to change its configuration is by deleting the trace or the server profile and adding it again with the new configuration.
Note
Note
Other Considerations and Limitations
1.
2.
3.
4.
5.
Configuring the Bearer Tracing Feature
Configuration Summary
The following steps provide a quick summary of the procedure for configuring the Bearer Tracing feature.
Step 1
Step 2
Step 3
Step 4
Step 5
Step 6
Detailed Configuration
To setup bearer tracing, use the following procedure.
Step 1
Step 2
This command is used to create a session with a specified DS0 or DS1 endpoint for bearer tracing. See T.38 Traces for T.38 endpoints.
The format of this command is:
addbearertraceendpt <endptIndex> <LineNum> <ds0> -trace <probe>
For <endptIndex> enter a number in the range 1 to 10. This parameter uniquely identifies the bearer trace session.
For <LineNum>, enter line number of the endpoint in one of the following formats.
Interface Type Line Number Format ValuesOC3/SDH bay.line.path.vtg.vt bay {1 - upper}
or bay.line.path.ds1 line (range=1..4)
path (range=1..3)
vtg (range=1..7)
vt (range=1..4)(ds1)
(range=1..3)(e1)
ds1 (range=1..28)T1/E1 bay.line bay {1 - upper}
line (range=1..24)T3 bay.line.ds1 bay {1 - upper}
line (range=1..6)
ds1 (range=1..28)For <ds0>, enter:
A number in the range 1 to 24 or "all" for a T1 interface
A number in the range 1 to 32 or "all" for an E1 interface
For -trace<probe>, enter the probe number(s) to be used in the session. Enter either a single number or multiple numbers, for example, 1,3,5,7)
1 = PCM Input
2 = PCM Output
4 = Network Input
5 = Network Output
3 = Sout (echo canceller output)
6 = VPU - Events
7 = T38 Level 2
8 = T38 Level 1
The line number "all" option can be used only when one of the probes 7 and 8 is chosen.
The creation of the session can be verified by using the dspbearertraceendpt command. The format of this command is:
dspbearertraceendpt <endptIndex>
Step 3
The syntax of this command is:
addbearertracesrvprof <profIndex> <srvIP> <xferMode> <fileNameBase>[<uploadPath> <portNumber/login><password>]
For <profIndex> enter a number in the range 1 to 10. This parameter uniquely identifies the bearer trace server profile.
For <srvIP>, enter the IP address of the server to receive the bearer trace reports. The IP address can be provided either using the regular "IP dot-notation" (nnn.nnn.nnn.nnn) or a name (alpha.beta.com) with a proper DNS support
For <xferMode>, specify the transfer mode for communicating with the server. Enter 0 for FTP, or 1 for TFTP
For <fileNameBase>, specify a fileNameBase. For FTP, the user can also enter "#" to indicate the default fileNameBase is to be used (default is not allowed for TFTP).
VXSM will generate filenames as follows:
For <uploadPath>, specify the path of the file in the server. For example. /pcm/tes
Note
For <portNumber/login>, enter a TFTP port number if xferMode = 1 or the FTP login name If xferMode = 0.
The TFTP port number is a number in the range 1 to 255 with a default of 69.
For login, use the FTP login name, default is "guest".
For <password>, use the FTP password, default is "guest".
The creation of the profile can be verified by using the dspbearertracesrvprof command. The format of this command is:
dspbearertracesrvprof <profIndex>
Step 4
The format of the addbearertrace command is:
addbearertrace <endptIndex> <profIndex> <active>
For <endptIndex>, enter the endpoint index number of the bearer trace session. A number in the range of 1 to 10.
For <profIndex>, enter the profile number of the bearer trace profile. A number in the range of 1 to10.
For <active>, specify 1 for enable or 0 for disable. If this parameter is omitted, the default is enable.
Note
The creation of the association can be verified by using the dspbearertrace command. The format of this command is:
dspbearertrace<endptIndex>
Examples of a Bearer Trace Configuration
Example 1.
This example procedure sets up the bearer tracing endpoint, the ftp/tftp server, and a method of mapping them to each other before making and tracing a call. The call is on ds0=1 on ds1=1.
Configuring the bearer tracing endpoint and the servers:
Step 1
martler.2.VXSM.a > addbearertraceendpt 1 1.1.1.1.1 1 -trace 1,2,5
Step 2
martler.2.VXSM.a > addbearertracesrvprof 1 172.17.38.159 0 sarang / root password
Step 3
martler.2.VXSM.a > addbearertrace 1 1 1
Step 4
martler.2.VXSM.a > dspbearertraceendpts
=============================================BEARER TRACE ENDPT PROFILES=============================================Index : 1line : 1.1.1.1.1lineNo : 1ds0No : 1bearerTraceSrvProf : 0x1 <---- Server Profile is addedbearerTraceProbes : 0x13Step 5
martler.2.VXSM.a > dspbearertracesrvprofs
=============================================BEARER TRACE SERVER PROFILES=============================================Server Profile Index : 1Bearer Trace Server IP : 172.17.38.159Server upload directory : /TFTP/FTP Mode : FTPFile Name Base : sarangFTP server login : rootFTP server password : password---------------------------------------------Step 6
-rw-r--r-- 1 root other 690480 Oct 16 12:17 pcminsarang_1.pcm
-rw-r--r-- 1 root other 690480 Oct 16 12:17 pcmoutsarang_1.pcm
-rw-r--r-- 1 root other 1380960 Oct 16 12:17 soutsarang_1.pcm
Example 2
The following example collects PCM traces for a call with both
endpoints on the same card:
Step 1
addbearertraceendpt 1 1.1.1.1.1 1 -trace 1,2
addbearertraceendpt 2 1.1.1.1.1 2 -trace 1,2
Step 2
addbearertracesrvprof 1 172.17.38.159 0 rxie /tftpboot root password
Step 3
addbearertrace 1 1 1
addbearertrace 2 1 1
When you make a call on endpoints 1 & 2 the PCM tracing will start automatically because of the last parameter in addbearertrace commsnd above.
However, If you use a different last parameter as in the following commands,
addbearertrace 1 1 0
addbearertrace 2 1 0
Tracing does not start automatically and the following commands are needed to start the tracing after the call is up:
bearertracestart 1
bearertracestart 2
Step 4
bearertracestop 1
bearertracestop 2
Trace Files
Server File Requirements
1.
2.
3.
FileNames
Bearer trace information is saved to the server as data chunks that will be stored in a file of which the name is generated by VXSM. The file naming scheme is slightly different depending upon whether TFTP or FTP are used as the transport protocol.
TFTP Filenames
Filenames used with TFTP consist of the following parts:
•
•
•
•
For example, a trace for PCM In on a bearertrace endpoint of index 1 and with a FilenameBase Mytrace would yield a filename of:
pcminMytrace_1.pcm
File names corresponding to trace files must be created on the server prior to enabling the bearer trace function. Further, VXSM must have write access to the trace files and the directory where they reside. The path to the file is relative to the default tftp directory (usually set as /tftpboot)
Note
FTP Filenames
For systems using FTP, the use of a FILENAMEBASE is optional. If a FILENAMEBASE is specified, the same file naming scheme used for TFTP is used (see previous paragraphs). If a FILENAMEBASE is not specified, VXSM will generate a filename having the following parts:
•
•
•
•
For example, a trace for PCM In on a bearertrace endpoint of index 1 would yield a filename of:
pcmin111205104520_1.pcm
Note
Note
Troubleshooting a Bearer Trace Operation
A number of issues can cause the trace to lose samples. In the bearer tracing infrastructure, the user needs to define the bearer tracing endpoints (ie: ds0) on which bearer traces are to be collected. The user needs to define bearer trace server where the bearer traces will be stored using FTP or TFTP. Any given bearer trace endpoint needs to be mapped to a bearer trace server, so that the bearer traces for that endpoint are stored at the mapped bearer trace server. The user can specify which directory the bearer traces can be stored and the base for the file names in which the traces are to be stored.
The user MUST make sure the following:
1.
2.
3.
4.
5.
6.
Summary of Bearer Trace Commands
The commands for the Bearer Trace feature are listed below. For detailed descriptions of these commands, please refer to the "Cisco Voice Switch Services (VXSM) Configuration Guide for MGX Switches and Media Gateways, Release 5.2"
addbearertraceendpt <endptIndex> <LineNum
