Netgear M7100-24X (XSM7224) - ProSAFE 24 Ports 10G Fully Managed L2 Switch Guia Do Programa
Routing
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M6100, M5300, and M7100 Series Managed Switches
ARP is a necessary part of the Internet Protocol (IP) and is used to translate an IP address to
a media (MAC) address, defined by a local area network (LAN) such as Ethernet. A station
needing to send an IP packet must learn the MAC address of the IP destination, or of the next
hop router, if the destination is not on the same subnet. This is achieved by broadcasting an
needing to send an IP packet must learn the MAC address of the IP destination, or of the next
hop router, if the destination is not on the same subnet. This is achieved by broadcasting an
ARP request packet, to which the intended recipient responds by unicasting an ARP reply
containing its MAC address. Once learned, the MAC address is used in the destination
address field of the Layer 2 header prepended to the IP packet.
address field of the Layer 2 header prepended to the IP packet.
The ARP cache is a table maintained locally in each station on a network. ARP cache entries
are learned by examining the source information in the ARP packet payload fields, regardless
of whether it is an ARP request or response. Thus, when an ARP request is broadcast to all
stations on a LAN segment or virtual LAN (VLAN), each recipient has the opportunity to store
the sender’s IP and MAC address in its respective ARP cache. The ARP response, being
unicast, is normally seen only by the requestor, who stores the sender information in its ARP
cache. Newer information always replaces existing content in the ARP cache.
are learned by examining the source information in the ARP packet payload fields, regardless
of whether it is an ARP request or response. Thus, when an ARP request is broadcast to all
stations on a LAN segment or virtual LAN (VLAN), each recipient has the opportunity to store
the sender’s IP and MAC address in its respective ARP cache. The ARP response, being
unicast, is normally seen only by the requestor, who stores the sender information in its ARP
cache. Newer information always replaces existing content in the ARP cache.
The number of supported ARP entries is platform dependent.
Devices can be moved in a network, which means that the IP address that was at one time
associated with a certain MAC address is now found using a different MAC, or it disappeared
from the network altogether (for example, it was reconfigured, disconnected, or powered off).
This leads to stale information in the ARP cache unless entries are updated in reaction to
new information seen on the network, periodically refreshed to determine if an address still
exists, or removed from the cache if the entry was identified as a sender of an ARP packet
during the course of an ageout interval, usually specified through configuration.
associated with a certain MAC address is now found using a different MAC, or it disappeared
from the network altogether (for example, it was reconfigured, disconnected, or powered off).
This leads to stale information in the ARP cache unless entries are updated in reaction to
new information seen on the network, periodically refreshed to determine if an address still
exists, or removed from the cache if the entry was identified as a sender of an ARP packet
during the course of an ageout interval, usually specified through configuration.
Configure Basic ARP Cache
Use this screen to show ARP entries in the ARP cache.
To display ARP entries in the ARP cache:
1.
Prepare your computer with a static IP address in the 169.254.100.0 subnet, for
example, 169.254.100.201.
2.
Connect an Ethernet cable from an Ethernet port on your computer to an Ethernet port on
the switch.
3.
Launch a web browser.
4.
Enter the IP address of the switch in the web browser address field.
The default IP address of the switch is 169.254.100.100.
The Login screen displays.
5.
Enter the user name and password.
The default admin user name is admin and the default admin password is blank, that is,
do not enter a password.
do not enter a password.
6.
Click the Login button.
The web management interface menu displays.