H3C Technologies H3C SecPath F1000-E - Manual (Page 14)

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A main advantage of proxy ARP is that it is added on a single device without disturbing routing tables
of other devices in the network. Proxy ARP acts as the gateway for hosts that are not configured with a
default gateway or do not have routing capability.
Local Proxy ARP
As shown in Figure 5 , Host A and Host B belong to VLAN 2, but are isolated at Layer 2. Host A connects
to GigabitEthernet 1/3 while Host B connects to GigabitEthernet 1/1. Enable local proxy ARP on Router
to allow Layer 3 communication between the two hosts.
Figure 5 Application environment of local proxy ARP
GE0/2
VLAN 2
Vlan-int2
192.168.10.100/16
Switch
GE1/3
GE1/1
GE1/2
uplink-port
Host A
192.168.10.99/16
Host B
192.168.10.200/16
VLAN 2
port-isolate group 2
Device
In one of the following cases, you need to enable local proxy ARP:
• Hosts connecting to different isolated Layer 2 ports in the same VLAN need to communicate at Layer
3.
• If a super VLAN is configured, hosts in different sub VLANs of the super VLAN need to communicate
at Layer 3.
• If an isolate-user-VLAN is configured, hosts in different secondary VLANs of the isolate-user-VLAN
need to communicate at Layer 3.
Enabling Proxy ARP
Follow these steps to enable proxy ARP in VLAN interface view/Layer 3 Ethernet interface view/Layer 3
aggregate interface view:
To do… Use the command… Remarks
Enter system view system-view —
Enter interface view
interface interface-type
interface-number
—
Enable proxy ARP proxy-arp enable
Required
Disabled by default.
Follow these steps to enable local proxy ARP in VLAN interface view/Layer 3 Ethernet interface
view/Layer 3 aggregate interface view: