Specifications
4-12
Cisco AS5x00 Case Study for Basic IP Modem Services
11/24/1999
Section 4 Verifying Modem Performance
Initiating a Modem Loopback Test Call
Modem Management:
Modem Management Call Switching Module debugging is on
5300-NAS#
Tech Tip
For channel associated signaling (CAS), robbed bit signaling (RBS), and R2, use the
debug cas
command. If this command is not included in your software, use the
modem-mgmt csm debug-rbs
command; however, the
service internal
command is
required.
5300-NAS(config)#service internal
5300-NAS(config)#end
5300-NAS#modem-mgmt csm debug-rbs
At the time of this publication, the Cisco AS5800 does not support the
debug cas
command or
modem-mgmt csm debug-rbs
command. As a work-around, complete the
following steps:
1. Determine the slot positions of each card. Enter the
show dial-shelf
command.
2. Access the trunk card’s console port. Enter the
dsip console slave
X
command
where
X
is the slot of the card that you want to perform debugging on.
3. Enter the command
debug trunk cas port
port-number
timeslots
range.
Step 4
Ensure that your EXEC session receives logging and debug output from the NAS:
5300-NAS#terminal monitor
Step 5
From the client telnet session, telnet into one of the idle modems (not in use). To do this, telnet to an IP
address on the NAS (Ethernet or Loopback) followed by 2000 plus a TTY line number. This example
telnets to TTY line 1 (2001).
5300-NAS#telnet 172.22.66.23 2001
Trying 172.22.66.23, 2001 ... Open
Note
This step is also known as a reverse telnet.
For a Cisco AS5800, create an arbitrary IP host followed by a reverse telnet. Use the
show modem
shelf
/
slot
/
port
command to determine which modem is associated with which TTY line. The following
example telnets to TTY 500, which maps to modem 1/2/68.
5800-NAS#show modem 1/2/68
Mdm Typ Status Tx/Rx G Duration RTS CTS DCD DTR
--- --- ------ ----- - -------- --- --- --- ---
1/2/68 V.90 Idle 37333/31200 1 00:01:05 RTS CTS noDCD DTR
Modem 1/2/68, Cisco MICA modem (Managed), Async1/2/68, TTY500
Firmware Rev: 2.6.2.0
. . .
Snip
5800-NAS(config)#ip host mod500 2500 172.22.66.23
5800-NAS(config)#^Z
5800-NAS#telnet mod500
Trying mod500 (172.22.66.23, 2500)... Open