Command Reference Guide

3Com Router 5000 Family and Router 6000 Family looptest ● 255
Command Reference
View This command can be used in the following views:
■ Any view
Description Loop test is available only on synchronous serial interfaces (including those formed on
E1/T1/E1-F/T1-F interfaces) using SD701 chips.
A loop test on an interface starts by sending a test packet. If the interface is in a local
or line loop, the test packet just sent will loop back to the interface.
In addition to testing interface or line loops, you may use this command to test the
transmission quality of a loopback line.
The output of this command provides information about:
■ Receiving state of test packets. If a test packet does not loop back to the sending
interface upon timeout, the message “Wait time out” is displayed. If it does loop
back, information about number of bytes, sequence number, and delay is
displayed for the packet.
■ Final statistics about sent test packets, received test packets, lost packets, received
error packets, percentage of lost packets, percentage of error packets, delay in its
minimum/average/maximum, and test conclusion
For a line with a low transmission speed, increase the timeout waiting for receiving a
sent test packet.
Related Commands ■ loopback
■ fe1 loopback
■ ft1 loopback