Quidway V100R006C00 User manual
Quidway S2700 Series Ethernet Switches
V100R006C00
Configuration Guide - IP Service
Issue 01
Date 2011-07-15
HUAWEI TECHNOLOGIES CO., LTD.
Copyright © Huawei Technologies Co., Ltd. 2011. 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 describes the configurations of the IP services of the S2700, including the basic
knowledge and configurations of secondary IP addresses, DNS, IP performance, basic IPv6
functions. By reading this document, you can learn the concepts and configuration procedures
of IP services.
This document is intended for:
lPolicy planning engineers
lInstallation and commissioning engineers
lNM configuration engineers
lTechnical support 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.
Change History
Updates between document issues are cumulative. Therefore, the latest document issue contains
all changes made in previous issues.
Changes in Issue 01 (2011-07-15)
Initial commercial release.
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Contents
About This Document.....................................................................................................................ii
1 IP Addresses Configuration........................................................................................................1
1.1 Introduction to IP Addresses..............................................................................................................................2
1.2 Features of IP Addresses Supported by the S2700.............................................................................................2
1.3 Configuring IP Addresses for Interfaces............................................................................................................3
1.3.1 Establishing the Configuration Task.........................................................................................................3
1.3.2 Configuring a Primary IP Address for an Interface...................................................................................3
1.3.3 (Optional) Configuring a Secondary IP Address for an Interface.............................................................4
1.3.4 Checking the Configuration.......................................................................................................................4
1.4 Configuration Examples.....................................................................................................................................5
1.4.1 Example for Setting Primary and Secondary IP Addresses......................................................................5
2 ARP Configuration........................................................................................................................8
2.1 Overview of ARP...............................................................................................................................................9
2.2 ARP Features Supported by the S2700..............................................................................................................9
2.3 Configuring Static ARP....................................................................................................................................10
2.3.1 Establishing the Configuration Task.......................................................................................................10
2.3.2 Configuring Common Static ARP Entries...............................................................................................11
2.3.3 Configuring Static ARP Entries in a VLAN...........................................................................................11
2.3.4 Checking the Configuration.....................................................................................................................12
2.4 Optimizing Dynamic ARP................................................................................................................................12
2.4.1 Establishing the Configuration Task.......................................................................................................13
2.4.2 Modify the aging parameters of dynamic ARP.......................................................................................13
2.4.3 Enabling ARP Suppression Function......................................................................................................14
2.4.4 Enabling Layer 2 Topology Detection Function.....................................................................................14
2.4.5 Checking the Configuration.....................................................................................................................14
2.5 Configuring Routed Proxy ARP.......................................................................................................................15
2.5.1 Establishing the Configuration Task.......................................................................................................15
2.5.2 Configure an IP Addresses for the Interface............................................................................................16
2.5.3 Enabling the Routed Proxy ARP Function..............................................................................................16
2.5.4 Checking the Configuration.....................................................................................................................16
2.6 Configuring Proxy ARP Within a VLAN........................................................................................................17
2.6.1 Establishing the Configuration Task.......................................................................................................17
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2.6.2 Configure an IP Addresses for the Interface............................................................................................18
2.6.3 Enabling Proxy ARP Within a VLAN....................................................................................................18
2.6.4 Checking the Configuration.....................................................................................................................18
2.7 Configuring Proxy ARP Between VLANs.......................................................................................................19
2.7.1 Establishing the Configuration Task.......................................................................................................19
2.7.2 Configuring an IP Addresses for the Interface........................................................................................20
2.7.3 Enabling Proxy ARP Between VLANs...................................................................................................20
2.7.4 Checking the Configuration.....................................................................................................................20
2.8 Maintaining ARP..............................................................................................................................................21
2.8.1 Clearing ARP Entries..............................................................................................................................21
2.8.2 Monitoring Network Operation Status of ARP.......................................................................................21
2.8.3 Debugging ARP.......................................................................................................................................22
2.9 Configuration Examples...................................................................................................................................22
2.9.1 Example for Configuring ARP................................................................................................................22
2.9.2 Example for Configuring Routed Proxy ARP.........................................................................................25
2.9.3 Example for Configuring Intra-VLAN Proxy ARP................................................................................27
2.9.4 Example for Configuring Inter-VLAN Proxy ARP................................................................................29
2.9.5 Example for Configuring Layer 2 Topology Detection..........................................................................32
3 IP Performance Configuration..................................................................................................35
3.1 Introduction to IP Performance........................................................................................................................36
3.2 IP Performance Supported by the S2700..........................................................................................................36
3.3 Optimizing IP Performance..............................................................................................................................36
3.3.1 Establishing the Configuration Task.......................................................................................................36
3.3.2 Enabling an Interface to Check the Source IP Addresses of Packets......................................................37
3.3.3 Configuring ICMP Attributes..................................................................................................................38
3.3.4 Setting TCP Parameters...........................................................................................................................38
3.3.5 Checking the Configuration.....................................................................................................................39
3.4 Maintaining IP Performance.............................................................................................................................40
3.4.1 Clearing IP Performance Statistics..........................................................................................................40
3.4.2 Monitoring the Running Status of IP Performance.................................................................................41
3.4.3 Debugging IP Performance.....................................................................................................................41
3.5 Configuration Examples...................................................................................................................................42
3.5.1 Example for Disabling the Sending of ICMP Host Unreachable Packets...............................................42
4 DNS Configuration.....................................................................................................................46
4.1 Introduction to DNS.........................................................................................................................................47
4.2 DNS Supported by the S2700...........................................................................................................................47
4.3 Configuring DNS..............................................................................................................................................47
4.3.1 Establishing the Configuration Task.......................................................................................................47
4.3.2 Configuring Static DNS Entries..............................................................................................................48
4.3.3 Configuring Dynamic DNS.....................................................................................................................48
4.3.4 Checking the Configuration.....................................................................................................................49
4.4 Maintaining DNS..............................................................................................................................................50
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4.4.1 Clearing DNS Entries..............................................................................................................................50
4.4.2 Monitoring Network Operation Status of DNS.......................................................................................51
4.4.3 Debugging DNS......................................................................................................................................51
4.5 Configuration Examples...................................................................................................................................52
4.5.1 Example for Configuring DNS................................................................................................................52
5 Basic Configurations of IPv6.....................................................................................................56
5.1 Introduction to IPv6..........................................................................................................................................57
5.2 IPv6 Features Supported by the S2700.............................................................................................................57
5.3 Configuring an IPv6 Address for an Interface..................................................................................................59
5.3.1 Establishing the Configuration Task.......................................................................................................59
5.3.2 Enabling IPv6 Packet Forwarding Capability.........................................................................................60
5.3.3 Configuring an IPv6 Link-Local Address for an Interface......................................................................60
5.3.4 Configuring an IPv6 Global Unicast Address for an Interface................................................................61
5.3.5 Checking the Configuration.....................................................................................................................62
5.4 Configuring IPv6 Neighbor Discovery.............................................................................................................62
5.4.1 Establishing the Configuration Task.......................................................................................................62
5.4.2 Configuring Static Neighbors..................................................................................................................63
5.4.3 Enabling RA Message Advertising.........................................................................................................63
5.4.4 Setting the Interval for Advertising RA Messages..................................................................................64
5.4.5 Enabling Stateful Auto Configuration.....................................................................................................65
5.4.6 Configuring the Address Prefixes to Be Advertised...............................................................................65
5.4.7 Configuring Other Information to Be Advertised...................................................................................66
5.4.8 Checking the Configuration.....................................................................................................................67
5.5 Maintaining IPv6..............................................................................................................................................68
5.5.1 Clearing IPv6 Statistics...........................................................................................................................68
5.5.2 Monitoring the Running Status of IPv6...................................................................................................69
5.5.3 Debugging IPv6.......................................................................................................................................69
5.6 Configuration Examples...................................................................................................................................70
5.6.1 Example for Setting an IPv6 Address for an Interface............................................................................70
6 IPv6 DNS Configuration............................................................................................................74
6.1 Introduction to IPv6 DNS.................................................................................................................................75
6.2 IPv6 DNS Supported by the S2700..................................................................................................................75
6.3 Configuring IPv6 DNS.....................................................................................................................................75
6.3.1 Establishing the Configuration Task.......................................................................................................75
6.3.2 Configuring a Static IPv6 DNS Entry.....................................................................................................76
6.3.3 Configuring the Dynamic IPv6 DNS Services........................................................................................76
6.3.4 Checking the Configuration.....................................................................................................................77
6.4 Maintaining IPv6 DNS.....................................................................................................................................78
6.4.1 Clearing IPv6 DNS Entries......................................................................................................................78
6.4.2 Monitoring Network Operation Status of IPv6 DNS..............................................................................79
6.5 Configuration Examples...................................................................................................................................79
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6.5.1 Example for Configuring IPv6 DNS.......................................................................................................79
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1 IP Addresses Configuration
About This Chapter
By assigning IP addresses to network devices, you can enable data communications between
the network devices.
1.1 Introduction to IP Addresses
IP is the core of the TCP/IP protocol suite. The packets of the Transmission Control Protocol
(TCP), User Datagram Protocol (UDP), Internet Control Message Protocol (ICMP), and Internet
Group Membership Protocol (IGMP) are all transmitted in the format of IP datagrams. Devices
on different networks communicate with each other using their network layer addresses, namely
IP addresses.
1.2 Features of IP Addresses Supported by the S2700
IP addresses can be obtained through static manual configuration or DHCP.
1.3 Configuring IP Addresses for Interfaces
Assigning an IP address to a device on a network enables the device to communicate with the
other devices on the network.
1.4 Configuration Examples
This section provides several examples of IP address configuration.
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1.1 Introduction to IP Addresses
IP is the core of the TCP/IP protocol suite. The packets of the Transmission Control Protocol
(TCP), User Datagram Protocol (UDP), Internet Control Message Protocol (ICMP), and Internet
Group Membership Protocol (IGMP) are all transmitted in the format of IP datagrams. Devices
on different networks communicate with each other using their network layer addresses, namely
IP addresses.
To communicate with each other on Internet Protocol (IP) networks, each host must be assigned
an IP address.
An IP address is a 32-bit number that is composed of two parts, namely, the network ID and
host ID.
The network ID identifies a network and the host ID identifies a host on the network. If the
network IDs of hosts are the same, it indicates that the hosts are on the same network regardless
of their physical locations.
1.2 Features of IP Addresses Supported by the S2700
IP addresses can be obtained through static manual configuration or DHCP.
The S2700 supports IP address configuration through the following methods:
lManually configuring an IP address for an interface
lObtaining an IP address by DHCP
The S2700 supports the space overlapping of network segment addresses to save the address
space.
lDifferent IP addresses in the overlapped network segments but not same can be configured
on different interfaces of the same device. For example, after an interface on a device is
configured with the IP address 20.1.1.1/16, if another interface is configured with the IP
address 20.1.1.2/24, the system prompts a message. However, the configuration is still
successful; if another interface is configured with the IP address 20.1.1.2/16, the system
prompts an IP address conflict. The configuration fails.
lThe primary IP address and the secondary IP address in the overlapped network segments
but not same can be configured on the same interface. For example, after the interface is
configured with a primary IP address 20.1.1.1/24, if the secondary IP address is 20.1.1.2/16
sub, the system prompts a message. However, the configuration is still successful.
lThe primary IP address and the secondary IP address in the overlapped network segments
but not same can be configured on different interfaces of the same device. However, the
primary IP address and the secondary IP address cannot be the same. For example, after an
interface on a device is configured with the IP address 20.1.1.1/16, if another interface is
configured with the IP address 20.1.1.2/24 sub, the system prompts a message. However,
the configuration is still successful.
The S2700 supports 31-bit IP address masks. Therefore, there are only two IP addresses in a
network segment, that is, the network address and broadcast address. The two IP addresses can
be used as host addresses.
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1.3 Configuring IP Addresses for Interfaces
Assigning an IP address to a device on a network enables the device to communicate with the
other devices on the network.
1.3.1 Establishing the Configuration Task
This section describes the applicable environment, pre-configuration tasks, data preparation, and
configuration procedure for assigning an IP address to an interface.
Applicable Environment
To start IP services on an interface, configure the IP address for the interface. You can assign
several IP addresses to each interface. Among them, one is the primary IP address and the others
are secondary IP addresses.
Generally, you need to configure only a primary IP address for an interface. Secondary IP
addresses, however, are required in some cases. For instance, when a device connects to a
physical network through an interface, and computers on this network belong to two Class C
networks, you need to configure a primary IP address and a secondary IP address for this interface
to ensure that the device can communication with all computers on this network.
Pre-configuration Tasks
Before configuring an IP addresses for an interface, complete the following tasks:
lConfiguring the physical parameters for the interface and ensuring that the physical layer
status of the interface is Up
lConfiguring the link layer parameters for the interface and ensuring that the status of the
link layer protocol on the interface is Up
Data Preparation
To configure IP addresses for an interface, you need the following data.
No. Data
1Interface number
2 Primary IP address and subnet mask of the interface
3 (Optional) Secondary IP address and subnet mask of the interface
1.3.2 Configuring a Primary IP Address for an Interface
An interface can have only one primary IP address.
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Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
interface vlanif vlan-id
The VLANIF interface view is displayed.
Step 3 Run:
ip address ip-address { mask | mask-length }
A primary IP address is configured.
An interface has only one primary IP address. If the interface already has a primary IP address,
the newly configured primary IP address replaces the original one.
----End
1.3.3 (Optional) Configuring a Secondary IP Address for an
Interface
To enable an interface to communicate with several networks with different network IDs, you
need to assign a secondary IP address to this interface.
Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
interface vlanif vlan-id
The VLANIF interface view is displayed.
Step 3 Run:
ip address ip-address { mask | mask-length } sub
A secondary IP address is configured.
You can configure a maximum of 8 secondary IP addresses on an interface.
----End
1.3.4 Checking the Configuration
You can view the configuration of the IP address for an interface.
Prerequisite
The configurations of the IP addresses for the interface are complete.
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Procedure
lRun the display ip interface [ brief ] [ interface-type [ interface-number ] ] command to
check the IP configuration on the interface.
lRun the display interface [ interface-type [ interface-number ] ] command to check
interface information.
----End
1.4 Configuration Examples
This section provides several examples of IP address configuration.
1.4.1 Example for Setting Primary and Secondary IP Addresses
This section provides a configuration example of setting primary and secondary IP addresses.
Networking Requirements
As shown in Figure 1-1, Ethernet 0/0/1 of the Switch is connected to a LAN, in which hosts
belong to two different network segments, that is 172.16.1.0/24 and 172.16.2.0/24. It is required
that the Switch can access the two network segments but the host in 172.16.1.0/24 cannot
interconnect with the host in 172.16.2.0/24.
Figure 1-1 Networking diagram for setting IP addresses
172.16.1.0/24
172.16.2.0/24
Switch
Ethernet 0/0/1
VLANIF 100
172.16.1.1/24
172.16.2.1/24 sub
Configuration Roadmap
The configuration roadmap is as follows:
1. Analyze the address of the network segment to which each interface is connected.
2. Set the secondary IP addresses for an interface.
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Data Preparation
To complete the configuration, you need the following data.
lPrimary IP address and subnet mask of the VLANIF interface
lSecondary IP address and subnet mask of the VLANIF interface
Procedure
Step 1 Set the IP address for VLANIF 100 where Ethernet 0/0/1 of the Switch belongs.
<Quidway> system-view
[Quidway] vlan 100
[Quidway-Vlan100] quit
[Quidway] interface ethernet 0/0/1
[Quidway-Ethernet0/0/1] port hybrid pvid vlan 100
[Quidway-Ethernet0/0/1] port hybrid untagged vlan 100
[Quidway-Ethernet0/0/1] quit
[Quidway] interface vlanif 100
[Quidway-Vlanif100] ip address 172.16.1.1 24
[Quidway-Vlanif100] ip address 172.16.2.1 24 sub
Step 2 Verify the configuration.
# Ping a host on network segment 172.16.2.0 from Switch. The ping succeeds.
<Quidway> ping 172.16.1.2
PING 172.16.1.2: 56 data bytes, press CTRL_C to break
Reply from 172.16.1.2: bytes=56 Sequence=1 ttl=128 time=25 ms
Reply from 172.16.1.2: bytes=56 Sequence=2 ttl=128 time=27 ms
Reply from 172.16.1.2: bytes=56 Sequence=3 ttl=128 time=26 ms
Reply from 172.16.1.2: bytes=56 Sequence=4 ttl=128 time=26 ms
Reply from 172.16.1.2: bytes=56 Sequence=5 ttl=128 time=26 ms
--- 172.16.1.2 ping statistics ---
5 packet(s) transmitted
5 packet(s) received
0.00% packet loss
round-trip min/avg/max = 25/26/27 ms
Ping a host on network segment 172.16.2.0 from the Switch. The ping succeeds.
<Quidway> ping 172.16.2.2
PING 172.16.2.2: 56 data bytes, press CTRL_C to break
Reply from 172.16.2.2: bytes=56 Sequence=1 ttl=128 time=25 ms
Reply from 172.16.2.2: bytes=56 Sequence=2 ttl=128 time=26 ms
Reply from 172.16.2.2: bytes=56 Sequence=3 ttl=128 time=26 ms
Reply from 172.16.2.2: bytes=56 Sequence=4 ttl=128 time=26 ms
Reply from 172.16.2.2: bytes=56 Sequence=5 ttl=128 time=26 ms
--- 172.16.2.2 ping statistics ---
5 packet(s) transmitted
5 packet(s) received
0.00% packet loss
round-trip min/avg/max = 25/25/26 ms
----End
Configuration Files
Configuration file of the Switch
#
sysname Quidway
#
vlan 100
#
interface Vlanif100
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ip address 172.16.1.1 255.255.255.0
ip address 172.16.2.1 255.255.255.0 sub
#
interface Ethernet0/0/1
port hybrid pvid vlan 100
port hybrid untagged vlan 100
#
return
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2 ARP Configuration
About This Chapter
ARP can map an IP address to a MAC address and implements transmission of Ethernet frames.
2.1 Overview of ARP
An Ethernet device must support ARP. ARP implements dynamic mapping between Layer 3 IP
addresses and Layer 2 MAC addresses.
2.2 ARP Features Supported by the S2700
This section describes the ARP features supported by the S2700.
2.3 Configuring Static ARP
Static ARP indicates that there is a fixed mapping between an IP address and a MAC address.
Static ARP needs to be configured by an administrator.
2.4 Optimizing Dynamic ARP
If dynamic ARP is configured, the system automatically resolutes an IP address into an Ethernet
MAC address.
2.5 Configuring Routed Proxy ARP
Proxy ARP enables devices whose IP addresses belong to the same network segment but
different physical networks to communicate with each other.
2.6 Configuring Proxy ARP Within a VLAN
By configuring proxy ARP on a VLAN, you can interconnect isolated hosts on a VLAN.
2.7 Configuring Proxy ARP Between VLANs
By configuring inter-VLAN proxy ARP, you can interconnect hosts on different VLANs.
2.8 Maintaining ARP
The operations of ARP maintenance include clearing ARP statistics and monitoring ARP
operating status.
2.9 Configuration Examples
This section provides several configuration examples of ARP.
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2.1 Overview of ARP
An Ethernet device must support ARP. ARP implements dynamic mapping between Layer 3 IP
addresses and Layer 2 MAC addresses.
Each host or device on the Local Area Network (LAN) can be configured a 32-bit IP address to
communicate with others. The assigned IP address is independent of the hardware address.
On the Ethernet, a host or a device transmits and receives Ethernet frames according to a 48-bit
Medium Access Control (MAC) address. The MAC address is also called the physical address
or the hardware address, which is assigned to an Ethernet interface when equipment is produced.
Therefore, on an interconnected network, an address resolution mechanism is required to provide
the mapping between MAC addresses and IP addresses.
The Address Resolution Protocol (ARP) maps an IP address to the corresponding MAC address.
2.2 ARP Features Supported by the S2700
This section describes the ARP features supported by the S2700.
The S2700 supports dynamic ARP, static ARP, proxy ARP, and Layer 2 topology detection.
ARP
ARP is classified into the following types: dynamic ARP and static ARP.
lStatic ARP means the mapping between manually configured IP addresses and MAC
addresses.
lDynamic ARP means that the ARP mapping table is dynamically maintained by the ARP
protocol.
proxy ARP
The S2700 supports the following types of proxy ARP:
NOTE
The S2700SI does not support Intra-VLAN proxy ARP and Inter-VLAN proxy ARP.
lRouted proxy ARP
Proxy ARP lets the PCs or switchs on the same network segment but in different physical
networks communicate.
In actual applications, if the current host connected with a switch is not configured with a
default gateway address (that is, the host does not know how to reach the intermediate
system of the network), the host cannot forward data packets.
Routed proxy ARP is introduced to solve this problem. The host sends an ARP Request
message, requesting the MAC address of the destination host. After receiving such a
request, the switch enabled with proxy ARP answers with its own MAC address. By
"faking" its identity, the switch accepts responsibility for routing messages to the "real"
destination.
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The switch enabled with proxy ARP can also hide the details of the physical networks and
implement the communication between hosts that are in different physical networks but on
the same network segment.
lIntra-VLAN proxy ARP
In the scenario where two users belong to the same VLAN but user isolation is configured
in the VLAN, to implement communication between the two users, you need to enable
proxy ARP with a VLAN on the member interface of the VLAN.
The interface enabled with proxy ARP within a VLAN does not directly discard the ARP
Request messages that are not for themselves. Instead, it searches the ARP mappings table
for the corresponding ARP entries. In this case, if the switch is qualified to serve as a proxy,
the interface sends the MAC address of the switch to the sender of the ARP Request
message.
Proxy ARP within a VLAN implements the interworking between isolated users in the
same VLAN.
lInter-VLAN proxy ARP
In the scenario where two users belong to different VLANs, to implement communication
between the two users, you need to enable proxy ARP between VLANs on the member
interfaces of the VLANs.
The interfaces enabled with proxy ARP between VLANs do not directly discard the ARP
Request messages that are not for themselves. Instead, they search the ARP mappings tables
on themselves for the corresponding ARP entries. If the conditions for being a proxy are
met, the interface sends the MAC address of the switch to the sender of the ARP Request
message.
Proxy ARP between VLANs is mainly applied to the following situations:
–Implementing Layer 3 interworking between users in different VLANs
–Implementing interworking between sub-VLANs by enabling proxy ARP between
VLANs on the VLANIF interface of the super VLAN
2.3 Configuring Static ARP
Static ARP indicates that there is a fixed mapping between an IP address and a MAC address.
Static ARP needs to be configured by an administrator.
2.3.1 Establishing the Configuration Task
This section describes the applicable environment, pre-configuration tasks, data preparation, and
configuration procedure for configuring static ARP.
Applicable Environment
Static ARP is used in the following situations:
lFor the packets whose destination IP address is on another network segment, static ARP
can help these packets traverse a gateway of the local network segment so that the gateway
can forward the packets to their destination.
lWhen you need to filter out some packets with illegitimate destination IP addresses, static
ARP can bind these illegitimate addresses to a nonexistent MAC address.
Quidway S2700 Series Ethernet Switches
Configuration Guide - IP Service 2 ARP Configuration
Issue 01 (2011-07-15) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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Pre-configuration Tasks
Before configuring ARP, complete the following tasks:
lConfiguring physical parameters for the interface and ensuring that the status of the physical
layer of the interface is Up
lConfiguring link layer protocol parameters for the interface and ensuring that the status of
the link layer protocol on the interface is Up
lConfiguring the network layer protocol for the interface
Data Preparation
To configure ARP, you need the following data.
No. Data
1IP address and MAC address of the static ARP entry
2 VPN instance name and VLAN ID to which the static ARP entry belongs
2.3.2 Configuring Common Static ARP Entries
Static ARP entries are required for the communication between common interfaces.
Context
If static ARP and the Virtual Router Redundancy Protocol (VRRP) are enabled on a device
simultaneously, the virtual IP address of the VRRP backup group configured on the VLANIF
interface cannot be the IP address contained in the static ARP entries; otherwise, incorrect host
routes are generated and thus packets cannot be normally forwarded.
Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
arp static ip-address mac-address
Configure common static ARP entries.
NOTE
Static ARP entries keep valid when a device works normally.
----End
2.3.3 Configuring Static ARP Entries in a VLAN
In the scenario where two users belong to the same VLAN but user isolation is configured in
the VLAN, to implement communications between the two users, you need to enable static ARP
within the VLAN on the member interface of the VLAN.
Quidway S2700 Series Ethernet Switches
Configuration Guide - IP Service 2 ARP Configuration
Issue 01 (2011-07-15) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
11
Context
If static ARP and the Virtual Router Redundancy Protocol (VRRP) are enabled on a device
simultaneously, the virtual IP address of the VRRP backup group configured on the VLAN
interface cannot be the IP address contained in the static ARP entries; otherwise, incorrect host
routes are generated and thus packets cannot be normally forwarded.
Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Configure static ARP entries in a Virtual Local Area Network (VLAN).
To configure static ARP entries in a VLAN, do as follows:
lRun the arp static ip-address mac-address [ vid vlan-id interface interface-type interface-
number ] command.
To configure static ARP entries for VLANIF interfaces, if an ARP entry contains only the
IP address and MAC address, and the VLAN ID and outbound interface of the ARP packet
are not specified, the system selects the outbound interface automatically. If the VLAN ID
and outbound interface are specified, the system forwards the packet from the specified
outbound interface.
If the interface corresponding to the VLAN is bound to a Virtual Private Network (VPN),
the device can automatically associate the configured static ARP entry with the VPN. This
command is applicable to port-based VLANs.
NOTE
Static ARP entries keep valid when a device works normally.
----End
2.3.4 Checking the Configuration
You can view the configuration of static ARP.
Prerequisite
The configurations of the ARP function are complete.
Procedure
lRun the display arp statistics { all } command to check the statistics for ARP entries.
----End
2.4 Optimizing Dynamic ARP
If dynamic ARP is configured, the system automatically resolutes an IP address into an Ethernet
MAC address.
Quidway S2700 Series Ethernet Switches
Configuration Guide - IP Service 2 ARP Configuration
Issue 01 (2011-07-15) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
12
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