Troubleshooting guide

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Cisco Broadband Local Integrated Services Solution Troubleshooting Guide
OL-5169-01
Chapter 9 Troubleshooting Cisco Media Gateways
Physical Indicators
Verify that the lines between the Cisco BTS 10200 and the VISM are in service.
Verify that you can ping the VISM from the Cisco BTS 10200. If this fails, determine whether the routing
tables on the Cisco BTS 10200 have been configured correctly.
Verify that there is an entry for destination 10.0.0.0.
Verify that the Cisco BTS 10200 IP address has been added to the VISM’s list. Execute the CLI
command ‘dspdns’ to determine if the Cisco BTS 10200 IP address is configured. If not, add the
Cisco BTS 10200 IP address.
Calls Are Getting Rejected from VISM
There could be several reasons why calls could get rejected. Following are some of the most common
ones.
Verify state of the gateway. Execute the CLI command ‘dspgwstate’. If this indicates that the Gateway
has been commanded out of service or that the gw is in alarm state, execute the CLI ‘cnfgwis’ to bring
the Gateway into service.
Verify that the lines are added and in service. Verify that the appropriate lines have been enabled on the
VISM and that they are not in alarm. This is indicated by green LEDs on the front panel corresponding
to each of the lines. This can also be determined by using the CLI dsplns. If there is no problem here,
verify that the lines are in service. To determine the state of the line, do ‘dsplnstate <line number>’. If
the display indicates that the line has been configured OOS, execute the ‘cnflnis <line number>’ to bring
the line in service.
Verify that the endpoints have been added. This can be done by executing the CLI command dspendpts.
Use addendpt or addendpts to add the endpoints, if they have not already been added.
Verify that the VISM’s domain name configured on the VISM card matches whatever is configured on
the Cisco BTS 10200. Do ‘dspvismdn’ to display the domain name configured for the VISM. To
configure the VISM domain name, use the command - ‘cnfvismdn’.
Calls (CRCX msgs from the CA) can also get rejected if a connection already exists on the endpoint on
the VISM. In this case, the Cisco BTS 10200 is not synchronous with the VISM. The VISM will have
to be reset.
Messages sent from the Cisco BTS 10200/CA will be rejected by the VISM, if the Cisco BTS 10200 is
sending on a port that is not configured on the VISM for that CA. Messages sent from the VISM will
also be sent only to the port configured for that CA.
A snoop trace will be helpful in determining the cause of failure between the VISM and Cisco BTS
10200 and could help trace the problem. This can be started using the command - snoop -x 42 -ta <ip
address of CA> port <udp port of CA>.
Echo Can Be Heard on the Voice Call
Action
Make sure that the echo cancellation is turned on. Under ShellConn, do a dspm_disp_table to find out
whether a call has echo cancellation. The display from dspm_disp_table tells you which echo
cancellation DSP is used. Read from the display to find the tail length to which the echo cancellation is
provisioned. If the echo delay is longer than the provisioned tail length, the echo cancellation will not
work. Provision the tail length (cnfecantail) to a bigger value.