H3C Technologies H3C MSR 50 - Manual (Page 223)

icmp-extensions compliant command on the devices. For more information about this command,
see Layer 3—IP Services Command Reference.
For an IPv6 network:
• Enable sending of ICMPv6 timeout packets on the intermediate devices (devices between the
source and destination devices). If the intermediate devices are H3C devices, execute the ipv6
hoplimit-expires enable command on the devices. For more information about this command, see
Layer 3—IP Services Command Reference.
• Enable sending of ICMPv6 destination unreachable packets on the destination device. If the
destination device is an H3C device, execute the ipv6 unreachables enable command. For more
information about this command, see Layer 3—IP Services Command Reference.
Using a tracert command to identify failed or all nodes in a
path
Execute tracert commands in any view.
Task Command Remarks
• For an IPv4 network:
tracert [ -a source-ip | -f first-ttl | -m
max-ttl | -p port | -q packet-number
| -vpn-instance vpn-instance-name |
-w timeout ] * host
Display the routes from source to
destination.
Use either approach.
• For an IPv6 network:
tracert ipv6 [ -f first-ttl | -m max-ttl |
-p port | -q packet-number |
-vpn-instance vpn-instance-name |
-w timeout ] * host
For more information about the tracert lsp command, see MPLS Command Reference.
System debugging
The device supports debugging for the majority of protocols and features and provides debugging
information to help users diagnose errors.
Debugging information control switches
The following switches control the display of debugging information:
• Protocol debugging switch—Controls whether to generate the protocol-specific debugging
information.
• Screen output switch—Controls whether to display the debugging information on a certain screen.
As shown in Figure 64 , assume that the device can provide debugging for the three modules 1, 2, and
3. The debugging information can be output on a terminal only when both the protocol debugging
switch and the screen output switch are turned on.
Output of debugging information depends on the configurations of the information center and the
debugging commands of each protocol and functional module. Debugging information is typically
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