Brocade Communications Systems FastIron SX 1600, Руководство по настройке, Страница: 31 / 593

TABLE 2 IP global parameters - Layer 3 switches (continued)
Parameter Description Default
• Classless Interdomain Routing (CIDR)
format; example: 192.168.1.1/24
NOTE
Changing this parameter affects the
display of IP addresses, but you can
enter addresses in either format
regardless of the display setting.
Router ID The value that routers use to identify themselves
to other routers when exchanging route
information. OSPF and BGP4 use router IDs to
identify routers. RIP does not use the router ID. The IP address configured on the lowest-
numbered loopback interface.
If no loopback interface is configured, then the
lowest-numbered IP address configured on the
device.
Maximum Transmission Unit (MTU) The maximum length an Ethernet packet can be
without being fragmented. 1500 bytes for Ethernet II encapsulation
1492 bytes for SNAP encapsulation
Address Resolution Protocol (ARP) A standard IP mechanism that routers use to
learn the Media Access Control (MAC) address
of a device on the network. The router sends the
IP address of a device in the ARP request and
receives the device MAC address in an ARP
reply. Enabled
ARP rate limiting You can specify a maximum number of ARP
packets the device will accept each second. If the
device receives more ARP packets than you
specify, the device drops additional ARP packets
for the remainder of the one-second interval. Disabled
ARP age The amount of time the device keeps a MAC
address learned through ARP in the device ARP
cache. The device resets the timer to zero each
time the ARP entry is refreshed and removes the
entry if the timer reaches the ARP age.
NOTE
You also can change the ARP age on
an individual interface basis.
10 minutes
Proxy ARP An IP mechanism a router can use to answer an
ARP request on behalf of a host by replying with
the router's own MAC address instead of the
host. Disabled
Static ARP entries An ARP entry you place in the static ARP table.
Static entries do not age out. No entries
Time to Live (TTL) The maximum number of routers (hops) through
which a packet can pass before being discarded.
Each router decreases a packet TTL by 1 before
forwarding the packet. If decreasing the TTL
causes the TTL to be 0, the router drops the
packet instead of forwarding it. 64 hops
Directed broadcast forwarding A directed broadcast is a packet containing all
ones (or in some cases, all zeros) in the host
portion of the destination IP address. When a
router forwards such a broadcast, it sends a copy
of the packet out each of its enabled IP
interfaces. Disabled
Basic IP parameters and defaults - Layer 3 switches
FastIron Ethernet Switch Layer 3 Routing
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