Configuration Guide - IP Service(V200R002C00_01)

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Huawei AR2200-S Series Enterprise Routers

V200R002C00

Configuration Guide - IP Service

Issue 01

Date 2012-03-30

HUAWEI TECHNOLOGIES CO., LTD.


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Copyright Huawei Technologies Co., Ltd. 2012. All rights reserved.

No part of this document may be reproduced or transmitted in any form or by any means without prior written

consent of Huawei Technologies Co., Ltd.

Trademarks and Permissions

and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.

All other trademarks and trade names mentioned in this document are the property of their respective holders.

Notice

The purchased products, services and features are stipulated by the contract made between Huawei and the

customer. All or part of the products, services and features described in this document may not be within the

purchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information,and recommendations in this document are provided "AS IS" without warranties, guarantees or representations

of any kind, either express or implied.

The information in this document is subject to change without notice. Every effort has been made in the

preparation of this document to ensure accuracy of the contents, but all statements, information, and

recommendations in this document do not constitute the warranty of any kind, express or implied.

Huawei Technologies Co., Ltd.

Address: Huawei Industrial Base

Bantian, Longgang

Shenzhen 518129

People's Republic of China

Website: http://www.huawei.com

Email: [email protected]

Issue 01 (2012-03-30) Huawei Proprietary and Confidential

Copyright Huawei Technologies Co., Ltd.

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About This Document

Intended Audience

This document provides the basic concepts, configuration procedures, and configuration

examples in different application scenarios of the IP service feature supported by the AR2200-

S.

This document describes how to configure the IP service feature.

This document is intended for:

l Data configuration engineers

l Commissioning engineers

l Network monitoring engineers

l System maintenance engineers

Symbol Conventions

The symbols that may be found in this document are defined as follows.

Symbol Description

DANGER

Indicates a hazard with a high level of risk, which if not

avoided, will result in death or serious injury.

WARNINGIndicates a hazard with a medium or low level of risk, whichif not avoided, could result in minor or moderate injury.

CAUTION

Indicates a potentially hazardous situation, which if not

avoided, could result in equipment damage, data loss,

performance degradation, or unexpected results.

TIP Indicates a tip that may help you solve a problem or save

time.

NOTE Provides additional information to emphasize or supplement

important points of the main text.


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Command Conventions

The command conventions that may be found in this document are defined as follows.

Convention Description

Boldface The keywords of a command line are in boldface.

Italic Command arguments are in italics.

[ ] Items (keywords or arguments) in brackets [ ] are optional.

{ x | y | ... } Optional items are grouped in braces and separated by

vertical bars. One item is selected.

[ x | y | ... ] Optional items are grouped in brackets and separated by

vertical bars. One item is selected or no item is selected.

{ x | y | ... }* Optional items are grouped in braces and separated byvertical bars. A minimum of one item or a maximum of all

items can be selected.

[ x | y | ... ]* Optional items are grouped in brackets and separated by

vertical bars. Several items or no item can be selected.

& The parameter before the & sign can be repeated 1 to n times.

# A line starting with the # sign is comments.

Interface Numbering Conventions

Interface numbers used in this manual are examples. In device configuration, use the existing

interface numbers on devices.

Change History

Updates between document issues are cumulative. Therefore, the latest document issue contains

all updates made in previous issues.

Changes in Issue 01 (2012-03-30)

Initial commercial release.


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Contents

About This Document.....................................................................................................................ii

1 ARP Configuration........................................................................................................................1

1.1 ARP Overview....................................................................................................................................................3

1.2 ARP FeaturesSupported by the AR2200-S.......................................................................................................31.3 Configuring Static ARP......................................................................................................................................4

1.3.1 Establishing the Configuration Task.........................................................................................................4

1.3.2 Configuring a Static ARP Entry................................................................................................................5

1.3.3 Configuring a Static ARP Entry in a VLAN.............................................................................................5

1.3.4 Configuring a Static ARP Entry in a VPN Instance..................................................................................6

1.3.5 Checking the Configuration.......................................................................................................................6

1.4 Optimizing Dynamic ARP..................................................................................................................................7

1.4.1 Establishing the Configuration Task.................................................................... .....................................7

1.4.2 Adjusting Parameters of Dynamic ARP Entries........................................................................................8

1.4.3 Enabling ARP Suppression.......................................................................................................................9

1.4.4 Enabling Layer 2 Topology Detection......................................................................................................9

1.4.5 Checking the Configuration.......................................................................................................................9

1.5 Configuring Routed Proxy ARP.......................................................................................................................10

1.5.1 Establishing the Configuration Task.................................................................. .....................................10

1.5.2 Configuring an IP Addresses for an Interface.........................................................................................11

1.5.3 Configuring Routed Proxy ARP..............................................................................................................12

1.5.4 Checking the Configuration.....................................................................................................................12

1.6 Configuring Intra-VLAN Proxy ARP..............................................................................................................13

1.6.1 Establishing the Configuration Task.......................................................................................................131.6.2 Configuring an IP Address for an Interface.............................................................................................14

1.6.3 (Optional) Configuring the VLAN ID of a Sub-interface.......................................................................14

1.6.4 Enabling Intra-VLAN Proxy ARP..........................................................................................................15


1.7 Configuring Inter-VLAN Proxy ARP..............................................................................................................16

1.7.1 Establishing the Configuration Task.......................................................................................................16

1.7.2 Configuring an IP Addresses for an Interface.........................................................................................17

1.7.3 (Optional) Configuring the VLAN ID of the Sub-interface....................................................................18

1.7.4 Enabling Inter-VLAN Proxy ARP..........................................................................................................18



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1.8 Configuring ARP-Ping IP.................................................................................................................................20


1.8.2 Checking an IP Address by Using ARP-Ping IP.....................................................................................20

1.9 Configuring ARP-Ping MAC...........................................................................................................................21


1.9.2 Checking a MAC Address by Using ARP-Ping MAC............................................................................22

1.10 Maintaining ARP............................................................................................................................................23

1.10.1 Deleting ARP Entries............................................................................................................................23

1.10.2 Monitoring the ARP Running Status.....................................................................................................23

1.11 Configuration Examples.................................................................................................................................24

1.11.1 Example for Configuring Static ARP....................................................................................................24

1.11.2 Example for Configuring Routed Proxy ARP.......................................................................................27

1.11.3 Example for Configuring Intra-VLAN Proxy ARP..............................................................................29

1.11.4 Example for Configuring Inter-VLAN Proxy ARP..............................................................................32

1.11.5 Example for Configuring Layer 2 Topology Detection........................................................................34

2 IP Address Configuration..........................................................................................................38

2.1 IP Address Overview........................................................................................................................................39

2.2 IP Addresses Supported by the AR2200-S.......................................................................................................39

2.3 Configuring IP Addresses for an Interface.......................................................................................................39


2.3.2 Configuring a Primary IP Address for an Interface.................................................................................40

2.3.3 (Optional) Configuring a Secondary IP Address for an Interface...........................................................41


2.4 Configuring IP Address Unnumbered on an Interface.....................................................................................42


2.4.2 Configuring a Primary IP Address for the Interface from Which an IP Address Will Be Borrowed

..........................................................................................................................................................................43

2.4.3 Configuring IP Address Unnumbered on an Interface............................................................................43


2.5 Configuration Examples...................................................................................................................................45

2.5.1 Example for Configuring Primary and Secondary IP Addresses for an Interface...................................45

2.5.2 Example for Configuring IP Address Unnumbered on an Interface.......................................................46

3 Basic IPv6 Configuration...........................................................................................................50

3.1 Introduction to IPv6..........................................................................................................................................52

3.2 IPv6 Supported by the AR2200-S....................................................................................................................52

3.3 Configuring an IPv6 Address for an Interface..................................................................................................54


3.3.2 Enabling IPv6 Packet Forwarding Capability.........................................................................................55

3.3.3 Configuring an IPv6 Link-Local Address for an Interface......................................................................56

3.3.4 Configuring an IPv6 Global Unicast Address for an Interface................................................................57

3.3.5 Configuring an IPv6 Anycast Address for an Interface...........................................................................57






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3.4 Configuring IPv6 Neighbor Discovery.............................................................................................................59


3.4.2 Configuring Static Neighbors..................................................................................................................61

3.4.3 Enabling RA Message Advertising.........................................................................................................61

3.4.4 Setting the Interval for Advertising RA Messages..................................................................................62

3.4.5 Configuring the Address Prefixes to Be Advertised...............................................................................62

3.4.6 Configuring Other Information to Be Advertised...................................................................................63

3.4.7 Configuring the Default Router Priority and Route Information............................................................64


3.5 Configuring IPv4/IPv6 Dual Stacks.................................................................................................................66


3.5.2 Enabling IPv6 Packet Forwarding...........................................................................................................67

3.5.3 Configuring IPv4 and IPv6 Addresses for the Interface..........................................................................68


3.6 Configuring PMTU...........................................................................................................................................69

3.6.1 Establishing the Configuration Task.................................................................. .....................................70

3.6.2 Creating Static PMTU Entries.................................................................................................................70

3.6.3 Configuring PMTU Aging Time.............................................................................................................71


3.7 Configuring TCP6............................................................................................................................................72


3.7.2 Configuring TCP6 Timers.......................................................................................................................72

3.7.3 Configuring the Size of the TCP6 Sliding Window................................................................................733.7.4 Checking the Configuration.....................................................................................................................73

3.8 Maintaining IPv6..............................................................................................................................................75

3.8.1 Resetting IPv6..........................................................................................................................................75


3.9.1 Example for Configuring an IPv6 Address for an Interface....................................................................76

3.9.2 Example for Configuring IPv6 Neighbor Discovery...............................................................................78

4 DNS Configuration.....................................................................................................................82

4.1 DNS Overview.................................................................................................................................................83

4.2 DNS FeaturesSupported by the AR2200-S.....................................................................................................834.3 Configuring a DNS Client................................................................................................................................84


4.3.2 Configuring Static DNS...........................................................................................................................85

4.3.3 Configuring Dynamic DNS.....................................................................................................................85


4.4 Configuring DNS Proxy or Relay....................................................................................................................87


4.4.2 Configuring a DNS Server......................................................................................................................88

4.4.3 (Optional) Configuring DNS Spoofing...................................................................................................88

4.4.4 (Optional) Setting the Aging Time of DNS Entries................................................................................89





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4.5 Configuring a DDNS Client.............................................................................................................................90


4.5.2 Creating a DDNS Policy..........................................................................................................................91

4.5.3 Configuring a DDNS Policy....................................................................................................................91

4.5.4 Binding a DDNS Policy to an Interface..................................................................................................92


4.6 Maintaining DNS..............................................................................................................................................93

4.6.1 Deleting Dynamic DNS Entries of DNS Clients.....................................................................................93

4.6.2 Deleting DNS Entries of the DNS Proxy or Relay..................................................................................94

4.6.3 Manually Updating a DDNS Policy........................................................................................................94


4.7.1 Example for Configuring a DNS Client..................................................................................................94

4.7.2 Example for Configuring DNS Proxy.....................................................................................................974.7.3 Example for Configuring a DDNS Client.............................................................................................100

5 NAT Configuration...................................................................................................................104

5.1 NAT Overview...............................................................................................................................................105

5.2 NAT FeaturesSupported by the AR2200-S...................................................................................................106

5.3 Configuring NAT...........................................................................................................................................109

5.3.1 Establishing the Configuration Task.....................................................................................................109

5.3.2 Configuring an Address Pool................................................................................................................110

5.3.3 Associating an ACL with an Address Pool...........................................................................................111

5.3.4 Configuring Easy IP..............................................................................................................................1115.3.5 Configuring an Internal Server..............................................................................................................112

5.3.6 Configuring Static NAT........................................................................................................................112

5.3.7 Enabling NAT ALG..............................................................................................................................113

5.3.8 Configuring NAT Filtering....................................................................................................................113

5.3.9 Configuring NAT Mapping...................................................................................................................114

5.3.10 Configuring DNS Mapping.................................................................................................................115

5.3.11 Configuring Twice NAT.....................................................................................................................115

5.3.12 Checking the Configuration.................................................................................................................116


5.4.1 Example for Configuring the NAT Server............................................................................................117

5.4.2 Example for Configuring Outbound NAT.............................................................................................119

5.4.3 Example for Configuring Twice NAT...................................................................................................122

6 DHCP Configuration................................................................................................................125

6.1 DHCP Overview.............................................................................................................................................127

6.2 DHCP Features Supported by the AR2200-S.................................................................................................127

6.3 Configuring aDHCP Server Based on a Global Address Pool......................................................................128

6.3.1 Establishing the Configuration Task................................................................ .....................................128

6.3.2 Configuring an Interface to Select a Global Address Pool for IP Address Allocation..........................130

6.3.3 Configuring Global Address Pool Attributes........................................................................................130





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6.3.4 (Optional) Configuring the DNS Service and NetBIOS Service Dynamically on the DHCP Client

........................................................................................................................................................................132

6.3.5 (Optional) Configuring the Static DNS Service on a DHCP Client......................................................133

6.3.6 (Optional) Configuring the Static NetBIOS Service on a DHCP Client...............................................133

6.3.7 (Optional) Configuring User-Defined DHCP Options of the Global Address Pool.............................134

6.3.8 (Optional) Configuring the Function That Prevents Identical IP Addresses.........................................135

6.3.9 (Optional) Configuring the DHCP Data Saving Function.....................................................................136


6.4 Configuring aDHCP Server Based on an Interface Address Pool.................................................................138


6.4.2 Configuring Interface Address Pool Attributes.....................................................................................139

6.4.3 (Optional) Configuring the DNS Service and NetBIOS Service Dynamically on the DHCP Client

........................................................................................................................................................................140

6.4.4 (Optional) Configuring the Static DNS Service on a DHCP Client......................................................141

6.4.5 (Optional) Configuring the Static NetBIOS Service on a DHCP Client...............................................142

6.4.6 (Optional) Configuring User-Defined DHCP Options of the Interface Address Pool..........................143

6.4.7 (Optional) Configuring the Function That Prevents Identical IP Addresses.........................................143

6.4.8 (Optional) Configuring the DHCP Data Saving Function.....................................................................144

6.4.9 Checking the Configuration...................................................................................................................145

6.5 Configuring aDHCP Relay Agent.................................................................................................................146


6.5.2 Configuring an Interface to Function as a DHCP Relay Agent.............................................................147

6.5.3 Specifying a Server Group on the DHCP Relay Agent.........................................................................148

6.5.4 Binding a DHCP Server Group to a DHCP Relay Interface.................................................................149

6.5.5 (Optional) Configuring the DHCP Relay Agent to Instruct the DHCP Server to Reclaim the Client IP

address............................................................................................................................................................149


6.6 Configuring aDHCP/BOOTP Client.............................................................................................................151


6.6.2 (Optional) Configuring the DHCP/BOOTP Client Attributes..............................................................152

6.6.3 Enabling the DHCP/BOOTP Client......................................................................................................153


6.7 Configuring the DHCP Rate Limit Function..................................................................................................155

6.8 Maintaining DHCP.........................................................................................................................................157

6.8.1 ClearingDHCP Statistics......................................................................................................................157

6.8.2 Monitoring the Operating Status of DHCP...........................................................................................158

6.9 ConfigurationExamples.................................................................................................................................158

6.9.1 Examplefor Configuring a DHCP Server Based on a Global Address Pool in the Scenario Where DHCP

Clients and the DHCP Server Are on the Same Network Segment...............................................................158

6.9.2 Examplefor Configuring a DHCP Server Based on an Interface Address Pool in the Scenario Where

DHCP Clients and the Server Are on the Same Network Segment...............................................................162

6.9.3 Examplefor Configuring a DHCP Server and a DHCP Relay Agent When the DHCP Server and Clients

Are on Different Network Segments..............................................................................................................165

6.9.4 Examplefor Configuring the DHCP and BOOTP Clients....................................................................169





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6.9.5 Example for Configuring DHCP Rate Limit.........................................................................................173

7 IP Performance Configuration................................................................................................176

7.1 IP Performance Overview..............................................................................................................................177

7.2 IP Performance Features Supported by the AR2200-S..................................................................................1777.3 Optimizing IP Performance............................................................................................................................177

7.3.1 Establishing the Configuration Task................................................................................ .....................177

7.3.2 Checking Validity of Source IP Addresses of Received Packets..........................................................178

7.3.3 Controlling IP packets with Source Route Options...............................................................................179

7.3.4 Setting the Route Delivery Mode of an LPU........................................................................................179

7.3.5 Configuring an Interface to Forward Broadcast Packets.......................................................................179

7.3.6 Configuring an Outbound Interface to Fragment IP Packets.................................................................180

7.3.7 Configuring an Interface to Send ICMP Redirection Packets...............................................................180

7.3.8 Setting the Mode in Which Protocol Packets Are Sent.........................................................................181

7.3.9 Disabling the Routing and Forwarding Function on High-end LAN Cards..........................................182


7.4 Configuring Load Balancing for IP Packet Forwarding.................................................................................184


7.4.2 Configuring the Unequal-Cost Multiple Path During IP Packet Forwarding.......................................185


7.5 Configuring TCP Attributes...........................................................................................................................187

7.5.1 Establishing the Configuration Task................................................................................ .....................187

7.5.2 Setting Values of TCP Timers...............................................................................................................188

7.5.3 Setting the Aging Time of the PMTU...................................................................................................1887.5.4 Setting the Size of the TCP Sliding Window........................................................................................189

7.5.5 Setting the MSS of TCP Packets on an Interface..................................................................................189


7.6 Maintaining IP Performance...........................................................................................................................191

7.6.1 Clearing IP Performance Statistics........................................................................................................191

7.6.2 Monitoring the IP Running Status.........................................................................................................191


7.7.1 Examplefor Disabling the Sending of ICMP Redirection Packets.......................................................192

7.7.2 Example for Configuring UCMP..........................................................................................................195

8 IP Unicast PBR Configuration................................................................................................ 199

8.1 PBR Overview................................................................................................................................................200

8.2 PBR Supported by the AR2200-S..................................................................................................................200

8.3 Configuring IP Policy-based Routing.............................................................................................................200


8.3.2 Definingthe Matching Rule of PBR.....................................................................................................201

8.3.3 DefiningActions of PBR.......................................................................................................................202

8.3.4 Applying PBR........................................................................................................................................204







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8.4.1 Example for Configuring IP Unicast PBR............................................................................................205

9 UDP Helper Configuration......................................................................................................209

9.1 UDP Helper Overview....................................................................................................................................210

9.2 UDP Helper Features Supported by the AR2200-S.......................................................................................2109.3 Configuring UDP Helper................................................................................................................................211


9.3.2 Enabling UDP Helper............................................................................................................................211

9.3.3 (Optional) Configuring a UDP Port for Packets to Be Relayed............................................................212

9.3.4 Configuring a Destination Server..........................................................................................................212


9.4 Maintaining UDP Helper................................................................................................................................214

9.4.1 Clearing the UDP Helper Statistics.......................................................................................................214


9.5.1 Example for Configuring UDP Helper..................................................................................................214





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1ARP ConfigurationAbout This Chapter

ARP can map an IP address to a MAC address and implements transmission of Ethernet frames.

1.1 ARP Overview

ARP dynamically maps Layer 3 IP addresses to Layer 2 MAC addresses. An Ethernet device

must support ARP.

1.2 ARP Features Supported by the AR2200-S

This section describes ARP Features supported by the AR2200-S.

1.3 Configuring Static ARP

Static ARP entries record fixed mappings between IP addresses and MAC addresses. They are

configured manually by network administrators.

1.4 Optimizing Dynamic ARP

If dynamic ARP is configured, the system resolves an IP address into an Ethernet MAC address.

Dynamic ARP entries are maintained dynamically by the ARP protocol. You can adjust

parameters ofdynamic ARP entries such as the number of ARP probes and the aging time of

dynamic ARP entries to optimize forwarding performance of the AR2200-S.

1.5 Configuring Routed Proxy ARP

Routed proxyARP implements communication between devices on the same network segment

but on different physical networks.

1.6 Configuring Intra-VLAN Proxy ARP

Intra-VLAN proxy ARP enables hosts that are isolated at Layer 2 in a VLAN to communicate

with each other.

1.7 Configuring Inter-VLAN Proxy ARP

Inter-VLAN proxy ARP enables hosts in different sub-VLANs of a super-VLAN to

communicate with each other.

1.8 Configuring ARP-Ping IP

ARP-Ping IP checks whether an IP address on a LAN is in use by sending ARP packets.

1.9 Configuring ARP-Ping MAC

ARP-Ping MAC checks whether a MAC address on a LAN is in use by sending Internet Control

Management Protocol (ICMP) packets.


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1.10 Maintaining ARP

This section describes how to maintain ARP.

1.11 Configuration Examples





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1.1 ARP Overview

ARP dynamically maps Layer 3 IP addresses to Layer 2 MAC addresses. An Ethernet device

must support ARP.

On a LAN, a host or a network device must know the IP address of another host or network

device to send data to it. In addition, the physical address of the destination device must also be

known because IP packets are encapsulated in frames for transmission across a physical network.

Therefore, the mapping from an IP address to a physical address is required. ARP maps IP

addresses to physical addresses.

1.2 ARP Features Supported by the AR2200-S

This section describes ARP Features supported by the AR2200-S.

The AR2200-S supports dynamic ARP, static ARP, proxy ARP, and ARPing.

ARP

ARP is classified into the following types:

l Static ARP: Mappings between IP addresses and MAC addresses are configured manually.

l Dynamic ARP: Dynamic ARP entries are maintained by the ARP protocol.

Proxy ARP

The AR2200-S supports the following types of proxy ARP:

l Routed proxy ARP

Routed proxy ARP implements communication between devices on the same network

segment but on different physical networks.

If a device connected to the AR2200-S is not configured with a default gateway address

(that is, the device does not know how to reach the intermediate system of the network),

the device cannot forward data packets.

Routed proxy ARP solves this problem. A device sends an ARP Request packet to request

the MAC address of the destination host. After receiving the packet, the AR2200-S enabled

with proxy ARP replies with its own MAC address. The AR2200-S then functions as the

gateway to route packets to the actual destination.

Proxy ARP can also shield topologies of physical networks so that internal hosts of Ethernet

A and Ethernet B on different physical networks but on the same network segment can

communicate.

l Intra-VLAN proxy ARP

If two users belong to the same VLAN but port isolation is configured in the VLAN, to

enable the two users to communicate, you must enable intra-VLAN proxy ARP on an

interface associated with the VLAN.

If an interface on the AR2200-S is enabled with intra-VLAN proxy ARP, it does not discard

the ARP request packet that is destined for another interface. Instead, it searches for the

corresponding ARP entry of the interface. If the ARP entry is found, the interface sendsthe MAC address of the AR2200-S to the sender of the ARP request.





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Proxy ARP within a VLAN implements the interworking between isolated users in the

same VLAN.

l Inter-VLAN proxy ARP

If two users belong to different VLANs, to implement communication between the two

users, you must enable inter-VLAN proxy ARP on an interface associated with the VLANs.

If an interface on the AR2200-S is enabled with inter-VLAN proxy ARP, it does not discard

the ARP request packet that is destined for another interface. Instead, it searches for the

corresponding ARP entry of the interface. If the ARP entry is found, the interface sends

the MAC address of the AR2200-S to the sender of the ARP request.

Inter-VLAN proxy ARP implements the following functions:

Layer 3 communication between users in different VLANs

Communication between users in sub-VLANs (you must enable inter-VLAN proxy

ARP on the VLANIF interface corresponding to the super-VLAN)

ARPing

ARPing is classified into ARP-Ping IP and ARP-Ping MAC. ARPing facilitates maintenance of

deployed Layer 2 features.


ARP-Ping MAC checks whether a MAC address on a LAN is in use by sending Internet Control

Management Protocol (ICMP) packets.

1.3 Configuring Static ARP

Static ARP entries record fixed mappings between IP addresses and MAC addresses. They are

configured manually by network administrators.

1.3.1 Establishing the Configuration Task

Before configuring static ARP, familiarize yourself with the applicable environment, complete

the pre-configuration tasks, and obtain the data required for the configuration. This will help

you complete the configuration task quickly and accurately.

Applicable EnvironmentStatic ARP entries ensure communication between the local device and another specified device.

They use the specified MAC address to keep attackers from modifying mappings between IP

addresses and MAC addresses in static ARP entries.

When static ARP and the Virtual Router Redundancy Protocol (VRRP) are configured on the

router, the IP address in a static ARP entry cannot be set to the VRRP virtual IP address on a

sub-interface for dot1q VLAN tag termination, a sub-interface for VLAN tag termination, or a

VLANIF interface. Otherwise, an incorrect host route is generated, causing forwarding errors.

Pre-configuration Tasks

Before configuring static ARP, complete the following tasks:





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l Connecting interfaces and setting physical parameters for the interfaces to ensure that the

physical layer status of the interfaces is Up

l Setting link layer protocol parameters for interfaces to ensure that the link layer protocol

status on the interfaces is Up

l Setting network layer protocol parameters for the interfaces to ensure that the routingprotocol status on the interfaces is Up

Data Preparation

To configure static ARP, you need the following data.

No. Data

1 IP address and MAC address in a static ARP entry

2 Name of the VPN instance and ID of the VLAN that a static ARP entry

belongs to

3 Outbound interface of ARP packets

1.3.2 Configuring a Static ARP Entry

Static ARP entries are valid as long as the AR2200-S works properly.

Context

NOTE

To configure static ARP entries for double-tagged packets, run the arp static cevidcommand.

Procedure

Step 1 Run:system-view

The system view is displayed.

Step 2 Run:

arp staticip-address mac-address

A static ARP entry is configured.

----End

1.3.3 Configuring a Static ARP Entry in a VLAN

This section describes how to configure a static ARP entry in a VLAN.

Context

NOTE






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Procedure



Step 2 Run:arp staticip-address mac-addressvidvlan-idinterfaceinterface-type interface-

number

A static ARP entry is configured in a VLAN.

When configuring a static ARP entry in a VLAN, you must specify the outbound interface so

that the packets are sent out from the specified outbound interface.

----End

1.3.4 Configuring a Static ARP Entry in a VPN InstanceTo implement Layer 2 communication between devices in a VPN instance, you can configure

static ARP entries in the VPN instance.

Context

NOTE


Procedure



Step 2 Run:arp staticip-address mac-addressvpn-instancevpn-instance-name

A static ARP entry is configured for a VPN instance.

----End

1.3.5 Checking the Configuration

Procedure

l Run the display arp[ all] command to check all ARP entries, including static ARP entries

and dynamic ARP entries.

l Run the display arp networknet-numbernet-mask[ dynamic| static] command to check

ARP entries on the specified network segment.

l Run the display arp staticcommand to check static ARP entries.

l Run the display arp statistics{all| interfaceinterface-type interface-number} command

to check statistics on ARP entries on the AR2200-S or the specified interface.

----End





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Example

# Display all the static ARP entries. display arp staticIP ADDRESS MAC ADDRESS EXPIRE(M) TYPE INTERFACE VPN-INSTANCE

VLAN/CEVLAN PVC------------------------------------------------------------------------------1.1.1.1 0efc-0505-86e3 S--

10/-

129.102.0.1 0e00-fc01-0000 S--

11.0.0.1 aa00-fcc0-1200 S--3/-

------------------------------------------------------------------------------

Total:3 Dynamic:0 Static:3 Interface:0

# Display all the ARP entries. display arp allIP ADDRESS MAC ADDRESS EXPIRE(M) TYPE INTERFACE VPN-INSTANCE

VLAN/CEVLAN PVC

------------------------------------------------------------------------------

129.102.0.1 00e0-fc01-0000 S--118.118.118.1 0018-2000-0083 I - Vlanif11 vpna

10.1.1.1 0018-2000-0083 I - Vlanif10

100.1.1.116 0018-2000-0083 I - Eth2/0/0100.1.1.118 0001-0c01-3401 14 D-0 Eth2/0/0

100.1.1.4 0016-ecb7-a879 18 D-0 Eth2/0/0

------------------------------------------------------------------------------


1.4 Optimizing Dynamic ARP

If dynamic ARP is configured, the system resolves an IP address into an Ethernet MAC address.

Dynamic ARP entries are maintained dynamically by the ARP protocol. You can adjust

parameters of dynamic ARP entries such as the number of ARP probes and the aging time ofdynamic ARP entries to optimize forwarding performance of the AR2200-S.


Before optimizing Dynamic ARP, familiarize yourself with the applicable environment,

complete the pre-configuration tasks, and obtain the data required for the configuration. This

will help you complete the configuration task quickly and accurately.

Applicable Environment

Dynamic ARP entries are maintained dynamically by the ARP protocol. They can be aged out,

updated, or overridden by static ARP entries. When the aging time is reached or the interface is

Down, corresponding dynamic ARP entries are deleted.

The AR2200-S can dynamically create dynamic ARP entries. You can adjust parameters of

dynamic ARP entries to optimize forwarding performance of the AR2200-S.


Before optimizing Dynamic ARP, complete the following tasks:

l

Connecting interfaces and setting physical parameters for the interfaces to ensure that thephysical layer status of the interfaces is Up





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l Configuring the network layer protocol on the interfaces

Data Preparation

To optimize Dynamic ARP, you need the following data.

No. Data

1 Number of the interface where dynamic ARP entries are created

2 Maximum number of ARP probes

3 Aging time of dynamic ARP entries

1.4.2 Adjusting Parameters of Dynamic ARP Entries

When the AR2200-S frequently updates ARP entries, you can shorten the aging time of dynamic

ARP entries and the interval for ARP probes and increase the number of ARP probes.

Procedure



Step 2 Run:interfaceinterface-type interface-number

The interface view is displayed.

On the AR2200-S, you can adjust the parameters of parameters of dynamic ARP entries on

Ethernet interfaces, GE interfaces, Eth-Trunk interfaces, VLANIF interfaces, and VE interfaces.

Step 3 Run:arp expire-timeexpire-time

The aging time of dynamic ARP entries is set.

By default, the aging time is 1200s.

Step 4 Run:arp detect-timesdetect-times

The number of ARP probes is set.

By default, the maximum number of ARP probes is 3. When the aging time of a dynamic ARP

entry is reached, the AR2200-S sends an ARP probe packet to the peer device periodically. If

the AR2200-S does not receive an ARP Reply packet from the peer device after the specified

number of ARP probes, it deletes the ARP entry.

Step 5 (Optional) Run:arp detect-mode unicast





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An interface is configured to send ARP probe packets in unicast mode.

By default, an interface broadcasts ARP probe packets.

----End

1.4.3 Enabling ARP Suppression

If the system receives a great number of ARP packets from the same source at a time, it has to

update ARP entries repeatedly, causing performance deterioration. To ensure system

performance, you can enable ARP suppression. The system then only responds to the ARP

packets but does not update ARP entries.

Procedure



Step 2 Run:arp-suppress enable

ARP suppression is enabled.

By default, ARP suppression is disabled in the system but is enabled on VLANIF interfaces.

After ARP suppression is enabled, it takes effect for only Eth-Trunk interfaces and VLANIF

interfaces.

----End

1.4.4 Enabling Layer 2 Topology Detection

Layer 2 topology detection enables the system to update all the ARP entries in the VLAN that

a Layer 2 interface belongs to when the Layer 2 interface status changes from Down to Up.

Procedure



Step 2 Run:l2-topology detect enable

Layer 2 topology detection is enabled.

By default, Layer 2 topology detection is disabled.

----End


You can view the dynamic ARP configuration.





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Procedure

l Run the display arp[ all] command to check all ARP entries, including static ARP entries

and dynamic ARP entries.

l Run the display arp interfaceinterface-typeinterface-number[ vidvlan-id[ cevidcevlan-

id] ] command to check ARP entries on the specified interface.

l Run the display arp networknet-numbernet-mask[ dynamic| static] command to check

ARP entries on the specified network segment.

l Run the display arp dynamiccommand to check dynamic ARP entries.



----End

Example

# Run the display arp interfacecommand, and you can view ARP entries on GE1/0/0.

display arp interface gigabitethernet 1/0/0IP ADDRESS MAC ADDRESS EXPIRE(M) TYPE INTERFACE VPN-INSTANCE

VLAN/CEVLAN PVC------------------------------------------------------------------------------

192.168.1.11 0000-0a41-0201 I - GE1/0/0 r1

192.168.1.1 0000-0a41-0200 15 D-6 GE1/0/0 r1

------------------------------------------------------------------------------Total:2 Dynamic:1 Static:0 Interface:1

# Display all the dynamic ARP entries. display arp dynamicIP ADDRESS MAC ADDRESS EXPIRE(M) TYPE INTERFACE VPN-INSTANCE

VLAN/CEVLAN PVC

------------------------------------------------------------------------------10.137.217.210 00e0-fc01-0203 I - GE1/0/0

10.137.216.1 0025-9e38-a09e 20 D-0 GE1/0/0

10.137.217.208 00e0-fc01-0205 16 D-0 GE1/0/010.2.2.1 00e0-fc99-9999 I - Eth-Trunk0

10.6.3.34 00e0-fc01-0204 I - GE2/0/0.1

192.168.20.1 00e0-fc99-9999 I - Vlanif100

10.0.0.1 00e0-fc99-9999 I - Vlanif200------------------------------------------------------------------------------


1.5 Configuring Routed Proxy ARP

Routed proxy ARP implements communication between devices on the same network segmentbut on different physical networks.


Before configuring routed proxy ARP, familiarize yourself with the applicable environment,







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If two hosts on different network segments are not configured with the default gateways, you

can enable routed proxy ARP to on a routing device connecting the two hosts to resolve IP

addresses between the two hosts.


Before configuring routed proxy ARP, complete the following tasks:





Data Preparation

To configure routed proxy ARP, you need the following data.

No. Data

1 Number of the interface where routed proxy ARP is to be enabled

2 IP address of the interface where routed proxy ARP is to be enabled

1.5.2 Configuring an IP Addresses for an Interface

The IP address of the interface enabled with routed proxy ARP must be on the same networksegment as the IP address of the connected host on a LAN.

Procedure



Step 2 Run:interfaceinterface-typeinterface-number[.subinterface-number]


Routed proxy ARP can be enabled on Ethernet interfaces, Ethernet sub-interfaces, GE interfaces,

GE sub-interfaces, VE interfaces, Eth-Trunk interfaces, Eth-Trunk sub-interfaces, and VLANIF

interfaces. The preceding interfaces and sub-interfaces are Layer 3 interfaces and sub-interfaces.

Step 3 Run:ip addressip-address{ mask| mask-length}

An IP address is configured for the interface.

The IP address of the interface enabled with routed proxy ARP must be on the same network

segment as the IP address of the connected host on a LAN.

----End





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1.5.3 Configuring Routed Proxy ARP

Routed proxy ARP implements communication between devices on different subnets.

Procedure



Step 2 Run:interfaceinterface-type interface-number


Routed proxy ARP can be enabled on Ethernet interfaces, Ethernet sub-interfaces, GE interfaces,

GE sub-interfaces, VE interfaces, Eth-Trunk interfaces, Eth-Trunk sub-interfaces, and VLANIFinterfaces. The preceding interfaces and sub-interfaces are Layer 3 interfaces and sub-interfaces.

Step 3 Run:arp-proxy enable

Routed proxy ARP is enabled on the interface.

By default, routed proxy ARP is disabled on an interface.

----End


After configuring routed proxy ARP, you can view the configuration.

Procedure



l Run the display arp vpn-instancevpn-instance-name[ dynamic| static] command to

check ARP entries in the specified VPN instance.




----End

Example


display arp interface gigabitethernet 1/0/0

IP ADDRESS MAC ADDRESS EXPIRE(M) TYPE INTERFACE VPN-INSTANCE

VLAN/CEVLAN PVC------------------------------------------------------------------------------

192.168.1.11 0000-0a41-0201 I - GE1/0/0 r1

192.168.1.1 0000-0a41-0200 15 D-6 GE1/0/0 r1






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# Run the display arp vpn-instancecommand, and you can view all the ARP entries in the

VPN instance r1.

display arp vpn-instance r1IP ADDRESS MAC ADDRESS EXPIRE(M) TYPE INTERFACE VPN-INSTANCE

VLAN/CEVLAN PVC

------------------------------------------------------------------------------10.10.20.9 0018-2000-0083 I - Vlanif888

10.10.10.6 0018-2000-0083 I - Vlanif833


# Run the display arp statisticscommand, and you can view the statistics on ARP entries.

display arp statistics all

Dynamic:1 Static:0

1.6 Configuring Intra-VLAN Proxy ARP

Intra-VLAN proxy ARP enables hosts that are isolated at Layer 2 in a VLAN to communicate

with each other.


Before configuring intra-VLAN proxy ARP, familiarize yourself with the applicable

environment, complete the pre-configuration tasks, and obtain the required data. This will help

you complete the configuration task quickly and accurately.


If two users are connected to Layer 2 isolated interfaces in the same VLAN, you can enable

intra-VLAN proxy ARP to implement Layer 3 communication between the two users.


Before configuring intra-VLAN proxy ARP, complete the following tasks:



l Configuring a VLAN

l Configuring port isolation in a VLAN

Data Preparation

To configure intra-VLAN proxy ARP, you need the following data.

No. Data

1 Number of the interface where intra-VLAN proxy ARP is to be enabled

2 IP address of the interface where intra-VLAN proxy ARP is to be enabled

3 VLAN ID associated with the interface to be enabled with proxy ARP in a VLAN





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1.6.2 Configuring an IP Address for an Interface

The IP address of the interface must be on the same network segment as the IP addresses in the

associated VLAN.

Procedure



Step 2 Run:interface{ ethernet| gigabitethernet| eth-trunk} interface-number.sub-

interface-number

The sub-interface view is displayed.

Or, run:

interface vlanifvlan-id

The VLANIF interface view is displayed.

Intra-VLAN proxy ARP can be enabled on VLANIF interfaces, Ethernet sub-interfaces, GE

sub-interfaces, and Eth-Trunk sub-interfaces.



The IP address of the interface must be on the same network segment as the IP addresses in the

associated VLAN.

----End

1.6.3 (Optional) Configuring the VLAN ID of a Sub-interface

This section describes how to configure the VLAN ID of a sub-interface.

Context

NOTE

You must complete this task before you enable intra-VLAN proxy ARP on Ethernet sub-interfaces, GE

sub-interfaces, or Eth-Trunk sub-interfaces. You can skip step when you are enabling intra-VLAN proxy

ARP on the VLANIF interface.

Procedure



Step 2 Run:

interface{ ethernet| gigabitethernet|eth-trunk} interface-number.sub-interface-number





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Step 3 Run:control-vidviddot1q-termination

The control VLAN and encapsulation mode of the sub-interface are configured.

Step 4 Run:dot1q termination vidvid

The single VLAN ID for dot1q encapsulation on a sub-interface is configured.

----End

1.6.4 Enabling Intra-VLAN Proxy ARP

Intra-VLAN proxy ARP implements Layer 3 communication between isolated users in a VLAN.

Procedure




interface-number


Or, run:



Step 3 Run:arp-proxy inner-sub-vlan-proxy enable

Intra-VLAN proxy ARP is enabled.

By default, intra-VLAN proxy ARP is disabled.

----End


After configuring intra-VLAN proxy ARP, you can view the intra-VLAN proxy ARP

configuration.

Procedure










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----End

Example



VLAN/CEVLAN PVC

------------------------------------------------------------------------------

192.168.1.11 0000-0a41-0201 I - GE1/0/0 r1192.168.1.1 0000-0a41-0200 15 D-6 GE1/0/0 r1

------------------------------------------------------------------------------



VPN instance r1.


VLAN/CEVLAN PVC

------------------------------------------------------------------------------

10.10.20.9 0018-2000-0083 I - Vlanif88810.10.10.6 0018-2000-0083 I - Vlanif833

------------------------------------------------------------------------------



display arp statistics allDynamic:1 Static:0

1.7 Configuring Inter-VLAN Proxy ARP

Inter-VLAN proxy ARP enables hosts in different sub-VLANs of a super-VLAN to

communicate with each other.


Before configuring inter-VLAN proxy ARP, familiarize yourself with the applicable

environment, complete the pre-configuration tasks, and obtain the data required for the

configuration. This will help you complete the configuration task quickly and accurately.


The VLAN aggregation technology isolates broadcast domain by using multiple VLANs on a

physical network so that different VLANs belong to the same subnet. This technology introduces

the super-VLAN and sub-VLAN. A super-VLAN contains one or more sub-VLANs in different

broadcast domains. A sub-VLAN does not occupy an independent subnet segment. In a super-

VLAN, IP addresses of hosts in different sub-VLANs are on the subnet segment corresponding

to the super-VLAN.

Sub-VLANs use the same Layer 3 interface to communicate. This reduces subnet IDs and subnet

default gateway addresses. The VLAN aggregation function allows different broadcast domainsto use the same subnet address, implements flexible addressing, and saves IP addresses.





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Hosts in different sub-VLANs of a super-VLAN cannot communicate with each other. To enable

these hosts to communicate with each other, you can enable inter-VLAN proxy ARP on the sub-

interface or VLANIF interface corresponding to the super-VLAN.

Pre-configuration TasksBefore configuring inter-VLAN proxy ARP, complete the following tasks:



l Configuring VLAN aggregation

Data Preparation

To configure inter-VLAN proxy ARP, you need the following data.

No. Data1 Number of the interface where inter-VLAN proxy ARP is to be enabled

2 IP address of the interface where inter-VLAN proxy ARP is to be enabled

3 VLAN ID associated with the interface to be enabled with proxy ARP between

VLANs

1.7.2 Configuring an IP Addresses for an Interface

The IP address of the interface must be on the same network segment as the IP address of theuser in a VLAN that the interface belongs to.

Procedure




interface-number


Or, run:



Inter-VLAN proxy ARP can be enabled on VLANIF interfaces, Ethernet sub-interfaces, GE

sub-interfaces, and Eth-Trunk sub-interfaces.







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The IP address of the interface must be on the same network segment as the IP address of the

user in a VLAN that the interface belongs to.

----End

1.7.3 (Optional) Configuring the VLAN ID of the Sub-interfaceThis section describes how to configure the VLAN ID of the sub-interface.

Context

NOTE

You must complete this task before you enable inter-VLAN proxy ARP on Ethernet sub-interfaces, GE

sub-interfaces, or Eth-Trunk sub-interfaces. You can skip this task if you are enabling inter-VLAN proxy

ARP on the VLANIF interface.

ProcedureStep 1 Run:

system-view



interface-number


Step 3 Run:

control-vidviddot1q-termination

The control VLAN and encapsulation mode of the sub-interface are configured.

Step 4 Run:dot1q termination vidvid

The single VLAN ID for dot1q encapsulation on a sub-interface is configured.

----End

1.7.4 Enabling Inter-VLAN Proxy ARP

To implement communication between users in different sub-VLANs, enable inter-VLAN proxyARP on the sub-interface corresponding to the super-VLAN.

Procedure



Step 2 Run:interface{ ethernet| gigabitethernet| eth-trunk} interface-number.sub-interface-number






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Or, run:



Step 3 Run:arp-proxy inter-sub-vlan-proxy enable

Inter-VLAN proxy ARP is enabled.

By default, inter-VLAN proxy ARP is disabled.

----End


After configuring inter-VLAN proxy ARP, you can view the inter-VLAN proxy ARP

configuration.

Procedure








----End

Example



VLAN/CEVLAN PVC

------------------------------------------------------------------------------192.168.1.11 0000-0a41-0201 I - GE1/0/0 r1

192.168.1.1 0000-0a41-0200 15 D-6 GE1/0/0 r1

------------------------------------------------------------------------------



VPN instance r1.


VLAN/CEVLAN PVC------------------------------------------------------------------------------

10.10.20.9 0018-2000-0083 I - Vlanif888

10.10.10.6 0018-2000-0083 I - Vlanif833



display arp statistics allDynamic:1 Static:0





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1.8 Configuring ARP-Ping IP



Before configuring ARP-Ping IP, familiarize yourself with the applicable environment,





Before configuring an IP address for a device, ensure that this IP address is not in use by sending

ARP packets. You can configure ARP-Ping IP on the device.


Before configuring ARP-Ping IP, complete the following task:



Data Preparation

To configure ARP-Ping IP, you need the following data.

No. Data

1 IP address to be checked

1.8.2 Checking an IP Address by Using ARP-Ping IP

ARP-Ping IP checks whether an IP address on a LAN is in use by sending ARP Request packets.

Context

ARP-Ping IP checks whether an IP address on a LAN is in use by sending ARP packets. You

can also use the pingcommand to check whether an IP address is in use, but the result of this

method may be inaccurate. The pingcommand uses Layer 3 packets as ICMP Echo Request

packets. If the destination host or the routing device enabled with the firewall function is

configured not to respond to the ICMP Echo Request packets, the destination host or the routing

device does not send ICMP Reply packets. Consequently, the IP address is considered unused.

ARP packets, which are Layer 2 protocol packets, can pass through the firewall that is configured

not to reply to ICMP Echo Request packets; therefore, the result of ARP-Ping IP is accurate.


Configuration Guide - IP Service 1

Documents

Configuration Guide - IP Service(V200R002C00_01)