3Com Router 3031, Справочник по командам

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28 C
HAPTER
2: S
YSTEM
M
AINTENANCE
& M
ANAGEMENT
C
OMMANDS
vpn-instance vpn-instance-name: Sets the vpn-instance name of MPLS VPN to
specify the VPN attribute configured in this ping command, that is, name of the
associated vpn-instance created at the local.
host: Domain name or IP address of destination host.
ip: IP protocol is used.
Description
Using the ping command, you can check the IP network connection and whether
the host is reachable.
If the above parameters have not been specified, the following default settings will
be used:
An ECHO-REQUEST packet is sent for 5 times at most.
Socket is non-DEBUG mode.
Host is first regarded as an IP address. If it is not an IP address, domain name
resolution will be performed.
The filling begins at 0x01 and increases gradually until 0x09 and then repeats.
All information including statistics is displayed.
Router is not recorded.
The length of ECHO-REQUEST packet is 56 bytes.
The timeout time waiting for an ECHO-RESPONSE packet is 2000ms.
The ICMP packets other than ECHO-RESPONSE packets are not displayed.
The parameter vpn-instance is not defined.
Following is the process of executing the ping command:
A host sends an ICMP ECHO-REQUEST to a destination. If the connection to the
destination network is working normally, the destination host will be able to
receive the ICMP ECHO-REQUEST packet and send an ICMP ECHO-REPLY packet
back to the source host.
The ping command can be used to test the network for connection failure or
network line quality problem. The output information includes:
The state of the reply that a destination has made to each ECHO-REQUEST. It will
be “Request time out." if no reply has been received upon the expiration of the
timeout time. Otherwise, the state information will include the bytes of the reply
packet, packet sequence number, TTL, reply time etc.
The last statistic information includes the count of packets sent, the count of reply
packets received, the percentage of the packets that have no reply, and the
minimum, maximum, and average reply time settings.