华为交换机防止仿冒网关ARP***配置实例
二层交换机实现仿冒网关的ARP防***： 一、组网需求：1. 二层交换机阻止网络用户仿冒网关IP的ARP***
二、组网图： http://yw.gzhp.cn:8080/UploadFiles_8357/200707/20070703163511938.jpg
图1二层交换机防ARP***组网
S3552P是三层设备，其中IP：100.1.1.1是所有PC的网关，S3552P上的网关MAC地址为000f-e200-3999。PC-B上装有ARP***软件。现在需要对S3026C_A进行一些特殊配置，目的是过滤掉仿冒网关IP的ARP报文。
三、配置步骤 对于二层交换机如S3026C等支持用户自定义ACL(number为5000到5999)的交换机，可以配置ACL来进行ARP报文过滤。
全局配置ACL禁止所有源IP是网关的ARP报文 acl num 5000 rule 0 deny 0806 ffff 24 64010101 ffffffff 40 rule 1 permit 0806 ffff 24 000fe2003999 ffffffffffff 34 其中rule0把整个S3026C_A的端口冒充网关的ARP报文禁掉，其中斜体部分64010101是网关IP地址100.1.1.1的16进制表示形式。Rule1允许通过网关发送的ARP报文，斜体部分为网关的mac地址000f-e200-3999。
注意：配置Rule时的配置顺序，上述配置为先下发后生效的情况。
在S3026C-A系统视图下发acl规则：
packet-filter user-group 5000 这样只有S3026C_A上连网关设备才能够发送网关的ARP报文，其它主机都不能发送假冒网关的arp响应报文。
三层交换机实现仿冒网关的ARP防***
一、组网需求： 1. 三层交换机实现防止同网段的用户仿冒网关IP的ARP***
二、组网图 http://yw.gzhp.cn:8080/UploadFiles_8357/200707/20070703163512363.jpg
图2 三层交换机防ARP***组网
三、配置步骤
1. 对于三层设备，需要配置过滤源IP是网关的ARP报文的ACL规则，配置如下ACL规则： aclnumber 5000 rule 0 deny 0806 ffff 24 64010105 ffffffff 40 rule0禁止S3526E的所有端口接收冒充网关的ARP报文，其中斜体部分64010105是网关IP地址100.1.1.5的16进制表示形式。
2. 下发ACL到全局 packet-filter user-group 5000 仿冒他人IP的ARP防***
一、组网需求： 作为网关的设备有可能会出现错误ARP的表项，因此在网关设备上还需对用户仿冒他人IP的ARP***报文进行过滤。
二、组网图： 参见图1和图2
三、配置步骤： 1. 如图1所示，当PC-B发送源IP地址为PC-D的arp reply***报文，源mac是PC-B的mac (000d-88f8-09fa)，源ip是PC-D的ip(100.1.1.3)，目的ip和mac是网关(3552P)的，这样3552上就会学习到错误的arp，如下所示：
--------------------- 错误 arp 表项 --------------------------------
IP Address MAC Address VLAN>Port Name Aging Type
100.1.1.4 000d-88f8-09fa 1 Ethernet0/2 20 Dynamic
100.1.1.3 000f-3d81-45b4 1 Ethernet0/2 20 Dynamic
从网络连接可以知道PC-D的arp表项应该学习到端口E0/8上，而不应该学习到E0/2端口上。但实际上交换机上学习到该ARP表项在E0/2。上述现象可以在S3552上配置静态ARP实现防***： arp static 100.1.1.3 000f-3d81-45b4 1 e0/8 2. 在图2 S3526C上也可以配置静态ARP来防止设备学习到错误的ARP表项。
3. 对于二层设备(S3050C和S3026E系列)，除了可以配置静态ARP外，还可以配置IP+MAC+port绑定，比如在S3026C端口E0/4上做如下操作： am user-bind ip-addr 100.1.1.4 mac-addr 000d-88f8-09fa int e0/4 则IP为100.1.1.4并且MAC为000d-88f8-09fa的ARP报文可以通过E0/4端口，仿冒其它设备的ARP报文则无法通过，从而不会出现错误ARP表项。
四、配置关键点： 此处仅仅列举了部分Quidway S系列以太网交换机的应用。在实际的网络应用中，请根据配置手册确认该产品是否支持用户自定义ACL和地址绑定。仅仅具有上述功能的交换机才能防止ARP欺骗。实际配置时注意偏移量的值，如不清楚请咨询华为售后工程师。6503交换机配置实例：acl number 5000
rule 0 deny 0806 ffff 24 0a4e0401 ffffffff 40
rule 1 permit 0806 ffff 24 000fe218ded7 ffffffffffff 34interface GigabitEthernet1/0/9
description Connect-to-Vlan4_S3928TP_1_G1/1/1
duplex full
speed 1000
port link-type trunk
port trunk permit vlan all
qos
packet-filter inbound user-group 5000 rule 0 system-index 1
packet-filter inbound user-group 5000 rule 1 system-index 2 3900系列交换机配置实例：acl number 5000
rule 0 deny 0806 ffff 16 0a4e0401 ffffffff 32
rule 1 permit 0806 ffff 16 000fe218ded7 ffffffffffff 32
rule 2 deny 0806 ffff 16 00142a6cf8f4 ffffffffffff 32
rule 3 deny 0806 ffff 16 0a4e04ba ffffffffffff 32 86中交换机配置：<Build4-2_S3928TP>display current-configuration
#
local-server nas-ip 127.0.0.1 key huawei
#
domain default enable system
#
queue-scheduler wrr 1 2 3 4 5 9 13 15
#
radius scheme system
#
domain system
#
local-user panda
password simple pingafan
service-type telnet
level 3
#
acl number 5000
rule 0 deny 0806 ffff 24 0a4e0401 ffffffff 40
rule 1 permit 0806 ffff 24 000fe218ded7 ffffffffffff 34
#
vlan 1
#
vlan 10
#
vlan 40
#
interface Vlan-interface1
ip address 10.78.1.42 255.255.255.0
#
interface Vlan-interface40
#
interface Aux1/0/0
#
interface Ethernet1/0/1
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/2
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/3
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/4
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/5
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/6
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/7
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/8
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/9
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/10
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/11
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/12
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/13
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/14
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/15
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/16
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/17
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/18
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/19
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/20
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/21
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/22
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/23
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface Ethernet1/0/24
port access vlan 40
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
interface GigabitEthernet1/1/1
description Connect-to-S6503_G1/0/9
duplex full
speed 1000
port link-type trunk
port trunk permit vlan all
#
interface GigabitEthernet1/1/2
description Connect-to-S6503_G1/0/8
duplex full
speed 1000
port link-type trunk
port trunk permit vlan all
#
interface GigabitEthernet1/1/3
#
interface GigabitEthernet1/1/4
port link-type trunk
port trunk permit vlan all
packet-filter inbound user-group 5000 rule 0
packet-filter inbound user-group 5000 rule 1
#
sysname Build4-2_S3928TP
undo irf-fabric authentication-mode
#
interface NULL0
#
ip route-static 0.0.0.0 0.0.0.0 10.78.1.1 preference 60
#
snmp-agent
snmp-agent local-engineid 800007
页:
[1]