Port Statistics; Route Tracing; Ping Snoop - Nortel 8300 Troubleshooting Manual

20 Troubleshooting fundamentals
You can use Device Manager, the Nortel Command Line Interface (NNCLI),
or the Command Line Interface (CLI) to configure port mirroring.

Port statistics

The port statistics commands allow you to display information on received
and transmitted packets at the ports. The ingress and egress counts are
taken at the MAC layer. These counts are updated once every second.

Route tracing

The traceroute command records the route (the specific gateway
computers at each hop) through the internet between your computer and a
specified destination computer. It also calculates and displays the amount of
time each hop took. It is a handy tool both for understanding where problems
are in the Internet network and for getting a detailed sense of the internet.

Ping snoop

You can use the ping snoop feature to troubleshoot MultiLink Trunking (MLT)
and Split MultiLink Trunking (SMLT) networks. This feature displays the
route that IP traffic takes over an MLT or SMLT path. Ping snoop enables a
filter that copies Internet Control Message Protocol (ICMP) messages to the
CPU. The CPU then monitors the ICMP stream. The console displays the
port that is used for each IP traffic flow, from source to destination station.
There is no mechanism to prevent line rate ICMP traffic from going to the
CPU as a result of enabling ping snoop.
You create a ping snoop filter by specifying a source and destination IP
address. Then, you specify the ports on which you want to enable ping
snoop. Only one ping snoop filter is supported on a port. If an ICMP
request is received on any of the added ports, the source and destination IP
address and the port, on which the packet was received, are displayed on
the management console.
If you do not know the source and destination IP address, use 0.0.0.0/0.0.0.0
as a wild card. The wild card shows all of the ICMP flows though the port
or ports.
Ping snoop is limited by the maximum number of Access Control Groups
(ACGs) configured on the ports. The maximum is 1024 ACGs.
By design, ping snoop configurations are not saved to the configuration
file and are deleted by resetting the switch. In addition, your ping snoop
configuration is erased if you log off and then log on under a different
security level.
Copyright © 2007, Nortel Networks
.
Nortel Ethernet Routing Switch 8300
Troubleshooting
NN46200-704 01.01 Standard
4.0 29 October 2007