3Com Switch 4500 26-Port, Руководство по настройке

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Testing Tools for Network Connection 253
Table 276 Test Periodically if the IP address is Reachable
The Switch can ping an IP address every one minute to test if it is reachable. Three
PING packets can be sent at most for every IP address in every testing with a time
interval of five seconds. If the Switch cannot successfully ping the IP address after
the three PING packets, it assumes that the IP address is unreachable.
You can configure up to 50 IP addresses by using the command repeatedly.
tracert
The
tracert
is used for testing the gateways passed by the packets from the
source host to the destination one. It is mainly used for checking if the network is
connected and analyzing where the fault occurs in the network.
The execution process of
tracert
is described as follows: Send a packet with TTL
value as 1 and the first hop sends back an ICMP error message indicating that the
packet cannot be sent, for the TTL is timeout. Re-send the packet with TTL value
as 2 and the second hop returns the TTL timeout message. The process is carried
over and over until the packet reaches the destination. The purpose to carry out
the process is to record the source address of each ICMP TTL timeout message, so
as to provide the route of an IP packet to the destination.
Perform the following operation in all views.
Figure 70 The tracert Command
Operation Command
Configure the IP address
requiring periodical testing
end-station polling ip-address
ip-address
Delete the IP address requiring
periodical testing
undo end-station polling ip-address
ip-address
Operation Command
Trace route
tracert [ -a source-IP ] [ -f first-TTL ] [ -m max-TTL ]
[ -p port ] [ -q nqueries ] [ -w timeout ] string