3Com 4210 PWR, Configuration Manual

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43
N
ETWORK
C
ONNECTIVITY
T
EST
Network Connectivity
Test
ping You can use the ping command to check the network connectivity and the
reachability of a host.
This command can output the following results:
■
Response status for each ping packet. If no response packet is received within
the timeout time, the message "Request time out" is displayed. Otherwise, the
number of data bytes, packet serial number, TTL (time to live) and response
time of the response packet are displayed.
■
Final statistics, including the numbers of sent packets and received response
packets, the irresponsive packet percentage, and the minimum, average and
maximum values of response time.
tracert You can use the tracert command to trace the gateways that a packet passes
from the source to the destination. This command is mainly used to check the
network connectivity. It can also be used to help locate the network faults.
The executing procedure of the tracert command is as follows: First, the source
host sends a data packet with the TTL of 1, and the first hop device returns an
ICMP error message indicating that it cannot forward this packet because of TTL
timeout. Then, the source host resends the packet with the TTL of 2, and the
second hop device also returns an ICMP TTL timeout message. This procedure
goes on and on until the packet gets to the destination. During the procedure, the
system records the source address of each ICMP TTL timeout message in order to
offer the path that the packet passed through to the destination.
Table 359 The ping command
Operation Command Description
Check the IP network
connectivity and the
reachability of a host ping [ -a ip-address ] [ -c count
] [ -d ] [ -f ] [ -h ttl ] [ -i
interface-type
interface-number
] [ ip ] [ -n ] [
- p pattern ] [ -q ] [ -s
packetsize ] [ -t timeout ] [
-tos tos ] [ -v ] host
You can execute this
command in any view.