Specifications

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PA-T3+ Serial Port Adapter Installation and Configuration
OL-3505-03
Chapter 4 Configuring the PA-T3+
Checking the Configuration
returned before the specified timeout is displayed as a period (.). A series of exclamation points (!!!!!)
indicates a good connection; a series of periods (.....) or the messages [timed out] or [failed] indicate a
bad connection.
Following is an example of a successful ping command to a remote server with the address 10.0.0.10:
Router# ping 10.0.0.10 <Return>
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echoes to 10.0.0.10, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/15/64 ms
Router#
If the connection fails, verify that you have the correct IP address for the destination and that the device
is active (powered on), and repeat the ping command.
Proceed to the next section, “Using loopback Commands,” to finish checking network connectivity.
Using loopback Commands
With the loopback test, you can detect and isolate equipment malfunctions by testing the connection
between the PA-T3+ interface and a remote device such as a modem or a CSU/DSU. The loopback
command places an interface in loopback mode, which enables test packets that are generated from the
ping command to loop through a remote device or compact serial cable. If the packets complete the loop,
the connection is good. If not, you can isolate a fault to the remote device or compact serial cable in the
path of the loopback test.
Depending on the mode of the port, issuing the loopback command checks the following path:
• When no compact serial cable is attached to the PA-T3+ interface port, or if a DCE cable is attached
to a port that is configured as line protocol up, the loopback command tests the path between the
network processing engine and the interface port only (without leaving the network processing
engine and port adapter).
• When a DTE cable is attached to the port, the loopback command tests the path between the network
processing engine and the near (network processing engine) side of the DSU or modem to test the
PA-T3+ interface and compact serial cable.
Table 4-9 provides examples of the loopback {dte | local | network {line | payload} | remote}
command. The examples given are for interface 0 of a one-port PA-T3+ in port adapter slot 0 of a VIP
in chassis slot 10 of a Cisco 7500 series router:
Table 4-9 Using loopback Commands
Command Function Example
loopback dte Sets the interface into loopback data
terminal equipment (DTE). Loopback
DTE loops the router output data back
toward the router (after the LIU).
Router(config)# interface serial 1/0
router(config-if)# loopback dte
loopback local Sets the interface into local loopback
mode. Local loopback loops the router
output data back toward the router at the
framer.
Router(config)# interface serial
10/0/0
router(config-if)# loopback local