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DWS-1008 User’s Manual
D-Link Systems, Inc.
Configuring and Managing IP Interfaces and Services
The traceroute facility determines the address of the first hop by examining the source address
field of the ICMP time-exceeded message.
To identify the next hop, traceroute again sends a UDP packet, but this time with a TTL
value of 2. The first router decrements the TTL field by 1 and sends the datagram to the next
router. The second router sees a TTL value of 1, discards the datagram, and returns the
Time
Exceeded
message to the source. This process continues until the TTL is incremented to a
value large enough for the datagram to reach the destination host (or until the maximum TTL
is reached).
To determine when a datagram has reached its destination, traceroute sets the UDP destination
port in the datagram to a very large value, one that the destination host is unlikely to be using.
In addition, when a host receives a datagram with an unrecognized port number, it sends an
ICMP
Port Unreachable
error to the source. This message indicates to the traceroute facility
that it has reached the destination.
To trace a route to a destination subnet, use the following command:
traceroute
host
[
dnf
] [
no-dns
] [
port
port-num
] [
queries
num
] [
size
size
] [
ttl
hops
]
[
wait
ms
]
To trace the route to host
server1
, type the following command:
DWS-1008#
traceroute server1
traceroute to server1.example.com (192.168.22.7), 30 hops max, 38 byte packets
1 engineering-1.example.com (192.168.192.206) 2 ms 1 ms 1 ms
2 engineering-2.example.com (192.168.196.204) 2 ms 3 ms 2 ms
3 gateway_a.example.com (192.168.1.201) 6 ms 3 ms 3 ms
4 server1.example.com (192.168.22.7) 3 ms * 2 ms
In this example,
server1
is four hops away. The hops are listed in order, beginning with the
hop that is closest to the Switch and ending with the route’s destination.
IP Interfaces and Services Configuration Scenario
This scenario configures IP interfaces, assigns one of the interfaces to be the system IP
address, and configures a default route, DNS parameters, and time and date parameters.
1.
Configure IP interfaces on the
mgmt
and
roaming
VLANs, and verify the configuration
changes. Type the following commands:
DWS-1008#
set interface mgmt ip 10.10.10.10/24
success: change accepted.
DWS-1008#
set interface roaming ip 10.20.10.10/24
success: change accepted.
DWS-1008#
show interface