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ATM Switch Router Software Configuration Guide
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Chapter7 Configuring Virtual Connections
Configuring Interface and Connection Snoopi ng

Other Configuration Options for Snoop Test Port

Most inapplicable configurations on the test port interface are disregarded while in snoop mode.
However, the following configuration options are not valid when specified for the snoop test port and
may affect the proper operation of the snoop mode on the test port:
Diagnostic and PIF loopbacks of the snoop test port. These types of loopbacks do not function in
snooping mode since the PIF receive side signals are disabled.
Other physical layer loopbacks (line, cell, or payload) function normally when in snooping mode
since they loop toward the line and are unaffected by the lack of PIF receive input.
Interface pacing (with the rate for the snoop test port lower than the rate for the monitored port ).
Network-derived clock source using the snoop test port.
Clock-source = loop-timed for the snoop test port.
Caution You should ensure that all options are valid and configured correctly while in the snoop mode.
Configuring Interface Snooping
The atm snoop interface atm command enables a snoop test port. Cells transmitted from the snoop test
port are copies of cells from a single direction of a monitored port.
When in snoop mode, any prior permanent virtual connections to the snoop t est port remain in the down
state.
To configure interface port snooping, perform the following steps, beginning in global configuration
mode:
Example
The following example shows how to configure ATM interface12/1 /3 as the port in snoop mode to
monitor ATM interface3/0/0, tested in the receive direction:
Switch(config)# interface atm 12/1/3
Switch(config-if)# atm snoop interface atm 3/0/0 direction receive
Displaying Interface Snooping
To display the test port information, use the following EXEC command:
Command Purpose
Step1 Switch(config)# interface atm card/subcard/port
Switch(config-if)#
Selects the interface to be configured.
Step2 Switch(config-if)# atm snoop interface atm
card/subcard/port direction [receive | transmit]
Specifies the interface and direction to be
snooped.
Command Purpose
show atm snoop Displays the snoop configuration.