The switch enabled with proxy ARP can also hide the details of the physical networks and
implement the communication between hosts that are in different physical networks but on
the same network segment.
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Intra-VLAN proxy ARP
In the scenario where two users belong to the same VLAN but user isolation is configured
in the VLAN, to implement communication between the two users, you need to enable
proxy ARP with a VLAN on the member interface of the VLAN.
The interface enabled with proxy ARP within a VLAN does not directly discard the ARP
Request messages that are not for themselves. Instead, it searches the ARP mappings table
for the corresponding ARP entries. In this case, if the switch is qualified to serve as a proxy,
the interface sends the MAC address of the switch to the sender of the ARP Request
message.
Proxy ARP within a VLAN implements the interworking between isolated users in the
same VLAN.
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Inter-VLAN proxy ARP
In the scenario where two users belong to different VLANs, to implement communication
between the two users, you need to enable proxy ARP between VLANs on the member
interfaces of the VLANs.
The interfaces enabled with proxy ARP between VLANs do not directly discard the ARP
Request messages that are not for themselves. Instead, they search the ARP mappings tables
on themselves for the corresponding ARP entries. If the conditions for being a proxy are
met, the interface sends the MAC address of the switch to the sender of the ARP Request
message.
Proxy ARP between VLANs is mainly applied to the following situations:
–
Implementing Layer 3 interworking between users in different VLANs
–
Implementing interworking between sub-VLANs by enabling proxy ARP between
VLANs on the VLANIF interface of the super VLAN
2.3 Configuring Static ARP
Static ARP indicates that there is a fixed mapping between an IP address and a MAC address.
Static ARP needs to be configured by an administrator.
2.3.1 Establishing the Configuration Task
This section describes the applicable environment, pre-configuration tasks, data preparation, and
configuration procedure for configuring static ARP.
Applicable Environment
Static ARP is used in the following situations:
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For the packets whose destination IP address is on another network segment, static ARP
can help these packets traverse a gateway of the local network segment so that the gateway
can forward the packets to their destination.
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When you need to filter out some packets with illegitimate destination IP addresses, static
ARP can bind these illegitimate addresses to a nonexistent MAC address.
Quidway S2700 Series Ethernet Switches
Configuration Guide - IP Service
2 ARP Configuration
Issue 01 (2011-07-15)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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