Enabling The Support For Arp Requests From A Natural Network; Arp Configuration Example - H3C S7500E Series Operation Manual

Operation Manual – ARP
H3C S7500E Series Ethernet Switches

1.2.4 Enabling the Support for ARP Requests from a Natural Network

When learning MAC addresses, if the device finds that the source IP address of an
ARP packet and the IP address of the inbound interface are not on the same subnet,
the device will further judge whether these two IP addresses are on the same natural
network.
Suppose that the IP address of VLAN-interface 10 is 10.10.10.5/24 and that this
interface receives an ARP packet from 10.11.11.1/8. Because these two IP addresses
are not on the same subnet, VLAN-interface 10 cannot process the packet. With this
feature enabled, the device will make judgment on natural network basis. Because the
IP address of VLAN-interface 10 is a Class A address and its default mask length is 8,
these two IP addresses are on the same natural network. In this way, VLAN-interface
10 can learn the MAC address of the source IP address 10.11.11.1.
Follow these steps to enable the support for ARP requests from a natural network:
Enter system view
Enable the support for
ARP requests from a
natural network

1.2.5 ARP Configuration Example

I. Network requirements
Set the aging time for dynamic ARP entries to 10 minutes.
Enable the support for ARP requests from a natural network.
Set the maximum number of dynamic ARP entries that VLAN-interface 10 can
learn to 1000.
Add a static ARP entry, with the IP address being 192.168.1.1/24, the MAC
address being 000f-e201-0000, and the outbound port being GigabitEthernet
2/0/10 of VLAN 10.
II. Configuration procedure
<Sysname> system-view
[Sysname] arp timer aging 10
[Sysname] naturemask-arp enable
[Sysname] vlan 10
[Sysname-vlan10] port gigabitethernet 2/0/10
[Sysname-vlan10] quit
[Sysname] interface vlan-interface 10
[Sysname-vlan-interface10] arp max-learning-num 1000
To do...
system-view
naturemask-arp enable
Use the command...
1-6
Chapter 1 ARP Configuration
Remarks
—
Required
Disabled by default.