System Debugging; Introduction To System Debugging - 3Com 4210G Series Configuration Manual

To do...
Enable sending of
ICMP timeout
packets
Enable sending of
ICMP destination
unreachable packets
Display the routes
from source to
destination

System Debugging

Introduction to System Debugging

The device provides various debugging functions. For the majority of protocols and features supported,
the system provides corresponding debugging information to help users diagnose errors.
The following two switches control the display of debugging information:
Protocol debugging switch, which controls protocol-specific debugging information.
Screen output switch, which controls whether to display the debugging information on a certain
screen.
As Figure 21-3 illustrates, suppose the device can provide debugging for the three modules 1, 2, and 3.
Only when both the protocol debugging switch and the screen output switch are turned on can
debugging information be output on a terminal.
Figure 21-3 The relationship between the protocol and screen debugging switch
Debugging
information
1
Protocol
ON
debugging
switch
Screen output
switch
Use the command...
ip ttl-expires enable
ip unreachables enable
tracert [ -a source-ip | -f first-ttl | -m max-ttl |
-p port | -q packet-number | -vpn-instance
vpn-instance-name | -w timeout ] * host
tracert ipv6 [ -f first-ttl | -m max-ttl | -p port |
-q packet-number | -w timeout ] * host
Debugging
information
2 3
Protocol
ON debugging
OFF
switch
Screen output
OFF
switch
1 2
ON
OFF
ON
21-5
Remarks
Required
Disabled by default.
Required
Disabled by default.
Required
Use either approach
The tracert command is
applicable in an IPv4
network; the tracert ipv6
command is applicable in an
IPv6 network.
Available in any view
3
ON