技术在于专研
分类：
2007-02-09 14:35:01
通过NAT实现镜像服务器的负载均衡
STEP1:底层配置,定义内口外口.
R1(config)#int s2/1
R1(config-if)#ip ad 12.0.0.2 255.255.255.0
R1(config-if)#no sh
R1(config-if)#int f0
R1(config-if)#int f0/0
R1(config-if)#ip ad 10.0.0.1 255.255.255.0
R1(config-if)#no ip proxy-arp
R1(config-if)#no sh
R1(config-if)#do ping 10.0.0.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.0.0.2, timeout is 2 seconds:
..!!!
Success rate is 60 percent (3/5), round-trip min/avg/max = 120/130/144 ms
R1(config-if)#do ping 10.0.0.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.0.0.3, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 64/96/112 ms
R1(config-if)#exit
R1(config)#int s2/1
R1(config-if)#ip nat outside
R1(config-if)#int f0/0
R1(config-if)#ip nat inside
R2(config-line)#int s2/1
R2(config-if)#ip ad 12.0.0.1 255.255.255.0
R2(config-if)#no sh
R2(config-if)#int s2/2
R2(config-if)#ip ad 23.0.0.1 255.255.255.0
R2(config-if)#no sh
R2(config-if)#do ping 12.0.0.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 12.0.0.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 48/183/324 ms
R2(config-if)#do ping 23.0.0.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 23.0.0.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 64/148/232 ms
R3(config-line)#int s2/1
R3(config-if)#ip ad 23.0.0.2 255.255.255.0
R3(config-if)#no sh
STEP2:通过ACL定义本地的公网地址,作为来自外部访问的目标地址
R1(config)#access-list 1 permit 12.0.0.5 //定义进行转换后的目的地址,外部直接访问的地址
STEP3:定义内网的服务器地址池
R1(config)#ip nat pool serer 10.0.0.2 10.0.0.3 prefix-length 24 type rotary //定义外网访问的内网地址池的范围,并起一个池的名字,type rotay定义了自动负载均衡
STEP4:作基于目的地的转换.
R1(config)#ip nat inside destination list 1 pool serer //为内部目的地址应用到NAT中,以使外部能顺利访问本地服务
在R1上看一下是否已经做成镜像
R1#sho ip access
Standard IP access list 1
permit 12.0.0.5
从R3上TELNET测试一下看是否已经配置成功
R3#telnet 12.0.0.5
Trying 12.0.0.5 ... Open
User Access Verification
Password:
Serer2>
R1#debug ip nat
IP NAT debugging is on
R1#
00:46:33: NAT: s=23.0.0.2, d=12.0.0.5->10.0.0.3 [40625]
00:46:34: NAT: s=10.0.0.3->12.0.0.5, d=23.0.0.2 [3852]
00:46:34: NAT*: s=23.0.0.2, d=12.0.0.5->10.0.0.3 [40626]
00:46:34: NAT*: s=23.0.0.2, d=12.0.0.5->10.0.0.3 [40627]
00:46:34: NAT*: s=23.0.0.2, d=12.0.0.5->10.0.0.3 [40628]
00:46:34: NAT*: s=10.0.0.3->12.0.0.5, d=23.0.0.2 [3853]
00:46:34: NAT*: s=10.0.0.3->12.0.0.5, d=23.0.0.2 [3854]
00:46:34: NAT*: s=10.0.0.3->12.0.0.5, d=23.0.0.2 [3855
R3#telnet 12.0.0.5
Trying 12.0.0.5 ... Open
User Access Verification
Password:
Serer1>
R1#
00:47:15: NAT*: s=23.0.0.2, d=12.0.0.5->10.0.0.2 [13898]
00:47:15: NAT*: s=10.0.0.2->12.0.0.5, d=23.0.0.2 [50115]
00:47:15: NAT*: s=23.0.0.2, d=12.0.0.5->10.0.0.2 [13899]
00:47:15: NAT*: s=10.0.0.2->12.0.0.5, d=23.0.0.2 [50116]
00:47:16: NAT*: s=23.0.0.2, d=12.0.0.5->10.0.0.2 [13900]
00:47:16: NAT*: s=23.0.0.2, d=12.0.0.5->10.0.0.2 [13901]
00:47:16: NAT*: s=10.0.0.2->12.0.0.5, d=23.0.0.2 [50117]
00:47:16: NAT*: s=10.0.0.2->12.0.0.5, d=23.0.0.2 [50118]
从测试的结果看通过NAT已经成功实现镜像服务器的负载均衡.
R1的配置
R1#sh ru
Building configuration...
Current configuration : 1347 bytes
!
version 12.1
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname R1
!
ip subnet-zero
ip cef
!
no ip domain-lookup
!
ip audit notify log
ip audit po max-events 100
ip ssh time-out 120
ip ssh authentication-retries 3
!
interface FastEthernet0/0
ip address 10.0.0.1 255.255.255.0
no ip proxy-arp //关闭代理ARP
ip nat inside //定义内网口
duplex half
!
interface Serial2/0
no ip address
shutdown
serial restart-delay 0
!
interface Serial2/1
ip address 12.0.0.2 255.255.255.0
ip nat outside //定义的外网口
serial restart-delay 0
!
interface Serial2/2
no ip address
shutdown
serial restart-delay 0
!
interface Serial2/3
no ip address
shutdown
serial restart-delay 0
!
interface Serial3/0
no ip address
shutdown
serial restart-delay 0
!
interface Serial3/1
no ip address
shutdown
serial restart-delay 0
!
interface Serial3/2
no ip address
shutdown
serial restart-delay 0
!
interface Serial3/3
no ip address
shutdown
serial restart-delay 0
!
ip nat pool serer 10.0.0.2 10.0.0.3 prefix-length 24 type rotary //定义将进行自动负载均衡的内网地址
ip nat inside destination list 1 pool serer //把内部地址应用到NAT中,以使外网能正常访问
ip classless
ip route 0.0.0.0 0.0.0.0 Serial2/1 //默认路由条目
no ip http server
no ip http secure-server
!
access-list 1 permit 12.0.0.5 //外网将要访问的本地外网地址
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
stopbits 1
line aux 0
stopbits 1
line vty 5 15
!
end
