地址转换（NAT）

*******************************全部采用端口************************
ISP分配的ip202.99.160.129

interface fastethernet0/0
ip address 192.168.1.1 255.255.255.0
duplex auto
speed auto
in nat inside
no shutdown

interface fastethernet0/1
ip address 192.168.2..1 255.255.255.0
duplex auto
speed auto
in nat outside
no shutdown

ip nat pool OnlyYou 202.99.160.130 202.99.160.130 netmask 255.255.255.252
//OnlyYou代表地址池的名称。 2个202.99.160.130是代表只用一个ip做转换后ip.
access-list 1 permit 192.168.1.0 0.0.0.255
access-list 1 permit 192.168.2.0 0.0.0.255
ip nat inside source list1 pool OnlyYou overload




***********************动态地址转换+端口***********************
ISP分配的IP 有：202.99.160.130~190 255.255.255.192

Interface fastethernet0/1
Ip address 192.168.1.1 255.255.255.0
Ip address 192.168.2.1 255.255.255.0 secondary
Duplex auto
Speed auto
Ip nat inside
No shutdown

Interface serial 0/0
Ip address 202.99.160.129 255.255.255.192
Duplex auto
Speed auto
Ip nat outside
No shutdwon

Ip nat pool OutPort 202.99.160.190 202.99.160.190 netmask 255.255.255.192
Ip nat pool OutPool 202.99.160.130 202.99.160.190 netmask 255.255.255.192
Ip nat inside source list1 pool OutPort //192.168.1.0段主机全部转成202.99.160.190
Ip nat inside source list2 pool OutPool
//出于访问FTP站点等考虑：192.168.2.0和192.168.3.0段主机全部
//转成202.99.160.130到202.99.160.189中的所有地址。
Access-list1 permit 192.168.1.0 0.0.0.255
Access-list2 permit 192.168.2.0 0.0.0.255
Access-list2 permit 192.168.3.0 0.0.0.255



***********************静态地址转换***********************


ISP分配的IP地址是:211.82.220.80~211.82.220.87
211.82.220.81 255.255.255.248
要求Intranet上的Web.E-mail.Ftp.Media可以被外部访问.
Interface fastethernet0/0
Ip address 192.168.1.1 255.255.255.0
Duplex auto
Speed auto
Ip nat inside
No shutdown

Interface fastethernet0/1
Ip address 211.82.220.81 255.255.255.248
Speed auto
Duplex auto
Ip nat outside
No shutdown

Ip nat pool Outpool 211.82.220.86 211.82.20.86 netmask 255.255.255.248
Access-list 1 permit 192.168.1.2 0.0.0.255
Access-list 1 permit 192.168.1.3 0.0.0.255
Access-list 1 permit 192.168.1.4 0.0.0.255
Access-list 1 permit 192.168.1.5 0.0.0.255
Ip nat inside source list1 pool Outpool overload
Ip nat inside source static 192.168.1.2 211.82.220.82
Ip nat inside source static 192.168.1.3 211.82.220.83
Ip nat inside source static 192.168.1.4 211.82.220.84
Ip nat inside source static 192.168.1.5 211.82.220.85




******************NAT影射****************************
假如ISP提供的IP地址比较多还可以,但假如不是的时候(如就两个时),一个用于内网地址转换,另一个用于对外网提供服务.
ISP提供的内网上网IP

Interface ethernet0
Ip address 192.168.1.1 255.255.255.0
Duplex auto
Speed auto
Ip nat inside
No shutdown
Interface fastethernet0/0
Ip address 211.82.220.129 255.255.255.248
Duplex auto
Speed auto
Ip nat outside
No shutdown

Access-list 1 permit 192.168.1.0 0.0.0.255
Ip nat pool Everybody 211.82.220.130 211.82.220.130 network 255.255.255.252
Ip nat inside source list1 pool Everybody overload
Ip nat inside source static tcp 192.168.1.2 80 202.99.220.130 80
Ip nat inside source static tcp 192.168.1.3 21 202.99.220.130 21
Ip nat inside source static tcp 192.168.1.4 25 202.99.220.130 25
Ip nat inside source static tcp 192.168.1.5 110 202.99.220.130 110



*******************利用地址转换实现负载均衡********************
;当有如象腾讯公司似的多服务器时,使用路由器实现负载平衡,可以使它们有平等的访问机会.
Interface fastethernet0/1
Ip address 192.168.1.1 255.255.255.0
Duplex auto
Speed auto
Ip nat inside
No shutdown

Interface fastethernet0/0
Ip address 202.110.198.81 255.2555.255.248
Duplex auto
Speed auto
Ip nat outside
Access-list 1 permit 202.110.198.82
Access-list 2 permit 202.110.198.83
Access-list 3 permit 192.168.1.0 0.0.0.255
Ip nat pool Webser 192.168.1.2 192.168.1.3 255.255.255.248 type rotary
Ip nat pool Ftpser 192.168.1.4 192.168.1.5 255.255.255.248 type rotary
Ip nat pool normal 202.110.198.84 202.110.198.84 netmask 255.255.255.248
Ip nat inside destination list 1 pool Webser
Ip nat inside destination list 2 pool Ftpser