Huawei AR150 series User manual

Huawei AR150&200 Series Enterprise Routers
V200R002C00
Configuration Guide - IP Service
Issue 02
Date 2012-03-30
HUAWEI TECHNOLOGIES CO., LTD.

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]
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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
AR150/200.
This document describes how to configure the IP service feature.
This document is intended for:
lData configuration engineers
lCommissioning engineers
lNetwork monitoring engineers
lSystem 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.
WARNING
Indicates a hazard with a medium or low level of risk, which
if 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 by
vertical 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.
&<1-n> 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 02 (2012-03-30)
Based on issue 01 (2011-12-30), the document is updated as follows:
The following information is added:
lDisabling the Routing and Forwarding Function on High-end LAN Cards
The following information is modified:
l6.6.3 Enabling the DHCP/BOOTP Client
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Changes in Issue 01 (2011-12-30)
Initial commercial release.
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Contents
About This Document.....................................................................................................................ii
1 ARP Configuration........................................................................................................................1
1.1 ARP Overview....................................................................................................................................................3
1.2 ARP Features Supported by the AR150/200......................................................................................................3
1.3 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.......................................................................................................13
1.6.2 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
1.6.5 Checking the Configuration.....................................................................................................................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
1.7.5 Checking the Configuration.....................................................................................................................19
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1.8 Configuring ARP-Ping IP.................................................................................................................................19
1.8.1 Establishing the Configuration Task.......................................................................................................20
1.8.2 Checking an IP Address by Using ARP-Ping IP.....................................................................................20
1.9 Configuring ARP-Ping MAC...........................................................................................................................21
1.9.1 Establishing the Configuration Task.......................................................................................................21
1.9.2 Checking a MAC Address by Using ARP-Ping MAC............................................................................22
1.10 Maintaining ARP............................................................................................................................................22
1.10.1 Deleting ARP Entries............................................................................................................................22
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 AR150/200.....................................................................................................39
2.3 Configuring IP Addresses for an Interface.......................................................................................................39
2.3.1 Establishing the Configuration Task.......................................................................................................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
2.3.4 Checking the Configuration.....................................................................................................................41
2.4 Configuring IP Address Unnumbered on an Interface.....................................................................................42
2.4.1 Establishing the Configuration Task.......................................................................................................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
2.4.4 Checking the Configuration.....................................................................................................................44
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 AR150/200...................................................................................................................52
3.3 Configuring an IPv6 Address for an Interface..................................................................................................54
3.3.1 Establishing the Configuration Task.......................................................................................................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
3.3.6 Checking the Configuration.....................................................................................................................58
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3.4 Configuring IPv6 Neighbor Discovery.............................................................................................................59
3.4.1 Establishing the Configuration Task.......................................................................................................60
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
3.4.8 Checking the Configuration.....................................................................................................................65
3.5 Configuring IPv4/IPv6 Dual Stacks.................................................................................................................66
3.5.1 Establishing the Configuration Task.......................................................................................................66
3.5.2 Enabling IPv6 Packet Forwarding...........................................................................................................67
3.5.3 Configuring IPv4 and IPv6 Addresses for the Interface..........................................................................68
3.5.4 Checking the Configuration.....................................................................................................................69
3.6 Configuring PMTU...........................................................................................................................................69
3.6.1 Establishing the Configuration Task.......................................................................................................69
3.6.2 Creating Static PMTU Entries.................................................................................................................70
3.6.3 Configuring PMTU Aging Time.............................................................................................................70
3.6.4 Checking the Configuration.....................................................................................................................71
3.7 Configuring TCP6............................................................................................................................................72
3.7.1 Establishing the Configuration Task.......................................................................................................72
3.7.2 Configuring TCP6 Timers.......................................................................................................................72
3.7.3 Configuring the Size of the TCP6 Sliding Window................................................................................73
3.7.4 Checking the Configuration.....................................................................................................................73
3.8 Maintaining IPv6..............................................................................................................................................75
3.8.1 Resetting IPv6..........................................................................................................................................75
3.9 Configuration Examples...................................................................................................................................76
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 Features Supported by the AR150/200....................................................................................................83
4.3 Configuring a DNS Client................................................................................................................................84
4.3.1 Establishing the Configuration Task.......................................................................................................84
4.3.2 Configuring Static DNS...........................................................................................................................85
4.3.3 Configuring Dynamic DNS.....................................................................................................................85
4.3.4 Checking the Configuration.....................................................................................................................86
4.4 Configuring DNS Proxy or Relay....................................................................................................................87
4.4.1 Establishing the Configuration Task.......................................................................................................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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4.4.5 Checking the Configuration.....................................................................................................................90
4.5 Configuring a DDNS Client.............................................................................................................................90
4.5.1 Establishing the Configuration Task.......................................................................................................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
4.5.5 Checking the Configuration.....................................................................................................................93
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 Configuration Examples...................................................................................................................................94
4.7.1 Example for Configuring a DNS Client..................................................................................................94
4.7.2 Example for Configuring DNS Proxy.....................................................................................................98
4.7.3 Example for Configuring a DDNS Client.............................................................................................100
5 NAT Configuration...................................................................................................................104
5.1 NAT Overview...............................................................................................................................................105
5.2 NAT Features Supported by the AR150/200.................................................................................................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..............................................................................................................................111
5.3.5 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 Configuration Examples.................................................................................................................................117
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 AR150/200...............................................................................................127
6.3 Configuring a DHCP 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 Checking the Configuration...................................................................................................................136
6.4 Configuring a DHCP Server Based on an Interface Address Pool.................................................................137
6.4.1 Establishing the Configuration Task.....................................................................................................137
6.4.2 Configuring Interface Address Pool Attributes.....................................................................................138
6.4.3 (Optional) Configuring the DNS Service and NetBIOS Service Dynamically on the DHCP Client
........................................................................................................................................................................139
6.4.4 (Optional) Configuring the Static DNS Service on a DHCP Client......................................................140
6.4.5 (Optional) Configuring the Static NetBIOS Service on a DHCP Client...............................................141
6.4.6 (Optional) Configuring User-Defined DHCP Options of the Interface Address Pool..........................142
6.4.7 (Optional) Configuring the Function That Prevents Identical IP Addresses.........................................143
6.4.8 Checking the Configuration...................................................................................................................143
6.5 Configuring a DHCP Relay Agent.................................................................................................................144
6.5.1 Establishing the Configuration Task.....................................................................................................144
6.5.2 Configuring an Interface to Function as a DHCP Relay Agent.............................................................146
6.5.3 Specifying a Server Group on the DHCP Relay Agent.........................................................................147
6.5.4 Binding a DHCP Server Group to a DHCP Relay Interface.................................................................147
6.5.5 (Optional) Configuring the DHCP Relay Agent to Instruct the DHCP Server to Reclaim the Client IP
address............................................................................................................................................................148
6.5.6 Checking the Configuration...................................................................................................................148
6.6 Configuring a DHCP/BOOTP Client.............................................................................................................149
6.6.1 Establishing the Configuration Task.....................................................................................................149
6.6.2 (Optional) Configuring the DHCP/BOOTP Client Attributes..............................................................150
6.6.3 Enabling the DHCP/BOOTP Client......................................................................................................151
6.6.4 Checking the Configuration...................................................................................................................152
6.7 Configuring the DHCP Rate Limit Function..................................................................................................153
6.8 Maintaining DHCP.........................................................................................................................................156
6.8.1 Clearing DHCP Statistics......................................................................................................................156
6.8.2 Monitoring the Operating Status of DHCP...........................................................................................156
6.9 Configuration Examples.................................................................................................................................157
6.9.1 Example for 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...............................................................157
6.9.2 Example for 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...............................................................160
6.9.3 Example for Configuring a DHCP Server and a DHCP Relay Agent When the DHCP Server and Clients
Are on Different Network Segments..............................................................................................................164
6.9.4 Example for Configuring the DHCP and BOOTP Clients....................................................................167
6.9.5 Example for Configuring DHCP Rate Limit.........................................................................................172
7 IP Performance Configuration................................................................................................174
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7.1 IP Performance Overview..............................................................................................................................175
7.2 IP Performance Features Supported by the AR150/200.................................................................................175
7.3 Optimizing IP Performance............................................................................................................................175
7.3.1 Establishing the Configuration Task.....................................................................................................175
7.3.2 Checking Validity of Source IP Addresses of Received Packets..........................................................176
7.3.3 Controlling IP packets with Source Route Options...............................................................................176
7.3.4 Configuring an Interface to Forward Broadcast Packets.......................................................................177
7.3.5 Configuring an Outbound Interface to Fragment IP Packets.................................................................177
7.3.6 Configuring an Interface to Send ICMP Redirection Packets...............................................................178
7.3.7 Setting the Mode in Which Protocol Packets Are Sent.........................................................................178
7.3.8 Checking the Configuration...................................................................................................................179
7.4 Configuring Load Balancing for IP Packet Forwarding.................................................................................181
7.4.1 Establishing the Configuration Task.....................................................................................................181
7.4.2 Configuring the Unequal-Cost Multiple Path During IP Packet Forwarding.......................................182
7.4.3 Checking the Configuration...................................................................................................................183
7.5 Configuring TCP Attributes...........................................................................................................................184
7.5.1 Establishing the Configuration Task.....................................................................................................184
7.5.2 Setting Values of TCP Timers...............................................................................................................184
7.5.3 Setting the Aging Time of the PMTU...................................................................................................185
7.5.4 Setting the Size of the TCP Sliding Window........................................................................................185
7.5.5 Setting the MSS of TCP Packets on an Interface..................................................................................186
7.5.6 Checking the Configuration...................................................................................................................186
7.6 Maintaining IP Performance...........................................................................................................................187
7.6.1 Clearing IP Performance Statistics........................................................................................................187
7.6.2 Monitoring the IP Running Status.........................................................................................................188
7.7 Configuration Examples.................................................................................................................................189
7.7.1 Example for Disabling the Sending of ICMP Redirection Packets.......................................................189
8 IP Unicast PBR Configuration................................................................................................192
8.1 PBR Overview................................................................................................................................................193
8.2 PBR Supported by the AR150/200.................................................................................................................193
8.3 Configuring IP Policy-based Routing.............................................................................................................193
8.3.1 Establishing the Configuration Task.....................................................................................................193
8.3.2 Defining the Matching Rule of PBR.....................................................................................................194
8.3.3 Defining Actions of PBR.......................................................................................................................195
8.3.4 Applying PBR........................................................................................................................................197
8.3.5 Checking the Configuration...................................................................................................................197
8.4 Configuration Examples.................................................................................................................................198
8.4.1 Example for Configuring IP Unicast PBR............................................................................................198
9 UDP Helper Configuration......................................................................................................202
9.1 UDP Helper Overview....................................................................................................................................203
9.2 UDP Helper Features Supported by the AR150/200......................................................................................203
9.3 Configuring UDP Helper................................................................................................................................204
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9.3.1 Establishing the Configuration Task.....................................................................................................204
9.3.2 Enabling UDP Helper............................................................................................................................204
9.3.3 (Optional) Configuring a UDP Port for Packets to Be Relayed............................................................205
9.3.4 Configuring a Destination Server..........................................................................................................205
9.3.5 Checking the Configuration...................................................................................................................206
9.4 Maintaining UDP Helper................................................................................................................................207
9.4.1 Clearing the UDP Helper Statistics.......................................................................................................207
9.5 Configuration Examples.................................................................................................................................207
9.5.1 Example for Configuring UDP Helper..................................................................................................207
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1 ARP Configuration
About 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 AR150/200
This section describes ARP Features supported by the AR150/200.
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 of dynamic ARP entries such as the number of ARP probes and the aging time of
dynamic ARP entries to optimize forwarding performance of the AR150/200.
1.5 Configuring Routed Proxy ARP
Routed proxy ARP 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 AR150/200
This section describes ARP Features supported by the AR150/200.
The AR150/200 supports dynamic ARP, static ARP, proxy ARP, and ARPing.
ARP
ARP is classified into the following types:
lStatic ARP: Mappings between IP addresses and MAC addresses are configured manually.
lDynamic ARP: Dynamic ARP entries are maintained by the ARP protocol.
Proxy ARP
The AR150/200 supports the following types of proxy ARP:
lRouted 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 AR150/200 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 AR150/200 enabled
with proxy ARP replies with its own MAC address. The AR150/200 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.
lIntra-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 AR150/200 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
sends the MAC address of the AR150/200 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.
lInter-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 AR150/200 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 AR150/200 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 IP checks whether an IP address on a LAN is in use by sending ARP packets.
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 Environment
Static 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:
Huawei AR150&200 Series Enterprise Routers
Configuration Guide - IP Service 1 ARP Configuration
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Copyright © Huawei Technologies Co., Ltd.
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lConnecting interfaces and setting physical parameters for the interfaces to ensure that the
physical layer status of the interfaces is Up
lSetting link layer protocol parameters for interfaces to ensure that the link layer protocol
status on the interfaces is Up
lSetting network layer protocol parameters for the interfaces to ensure that the routing
protocol status on the interfaces is Up
Data Preparation
To configure static ARP, you need the following data.
No. Data
1IP 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 AR150/200 works properly.
Context
NOTE
To configure static ARP entries for double-tagged packets, run the arp static cevid command.
Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
arp static ip-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
To configure static ARP entries for double-tagged packets, run the arp static cevid command.
Huawei AR150&200 Series Enterprise Routers
Configuration Guide - IP Service 1 ARP Configuration
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5

Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
arp static ip-address mac-address vid vlan-id interface interface-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 Instance
To implement Layer 2 communication between devices in a VPN instance, you can configure
static ARP entries in the VPN instance.
Context
NOTE
To configure static ARP entries for double-tagged packets, run the arp static cevid command.
Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
arp static ip-address mac-address vpn-instance vpn-instance-name
A static ARP entry is configured for a VPN instance.
----End
1.3.5 Checking the Configuration
Procedure
lRun the display arp [ all ] command to check all ARP entries, including static ARP entries
and dynamic ARP entries.
lRun the display arp network net-number net-mask [ dynamic | static ] command to check
ARP entries on the specified network segment.
lRun the display arp static command to check static ARP entries.
lRun the display arp statistics { all | interface interface-type interface-number } command
to check statistics on ARP entries on the AR150/200 or the specified interface.
----End
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Configuration Guide - IP Service 1 ARP Configuration
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Copyright © Huawei Technologies Co., Ltd.
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Example
# Display all the static ARP entries.
<Huawei> display arp static
IP 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.
<Huawei> display arp all
IP 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 - Eth
100.1.1.118 0001-0c01-3401 14 D-0 Eth
100.1.1.4 0016-ecb7-a879 18 D-0 Eth
------------------------------------------------------------------------------
Total:6 Dynamic:2 Static:1 Interface:3
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 of
dynamic ARP entries to optimize forwarding performance of the AR150/200.
1.4.1 Establishing the Configuration Task
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 AR150/200 can dynamically create dynamic ARP entries. You can adjust parameters of
dynamic ARP entries to optimize forwarding performance of the AR150/200.
Pre-configuration Tasks
Before optimizing Dynamic ARP, complete the following tasks:
lConnecting interfaces and setting physical parameters for the interfaces to ensure that the
physical layer status of the interfaces is Up
Huawei AR150&200 Series Enterprise Routers
Configuration Guide - IP Service 1 ARP Configuration
Issue 02 (2012-03-30) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
7

lSetting link layer protocol parameters for interfaces to ensure that the link layer protocol
status on the interfaces is Up
lConfiguring the network layer protocol on the interfaces
Data Preparation
To optimize Dynamic ARP, you need the following data.
No. Data
1Number 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 AR150/200 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 1 Run:
system-view
The system view is displayed.
Step 2 Run:
interface interface-type interface-number
The interface view is displayed.
On the AR150/200, you can adjust the parameters of parameters of dynamic ARP entries on
Ethernet interfaces, Eth-Trunk interfaces, VLANIF interfaces, and VE interfaces.
Step 3 Run:
arp expire-time expire-time
The aging time of dynamic ARP entries is set.
By default, the aging time is 1200s.
Step 4 Run:
arp detect-times detect-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 AR150/200 sends an ARP probe packet to the peer device periodically. If
the AR150/200 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
Huawei AR150&200 Series Enterprise Routers
Configuration Guide - IP Service 1 ARP Configuration
Issue 02 (2012-03-30) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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