1、路由实例
路由实例是路由表、接口和路由协议参数的集合。通过设置接口及路由协议各种参数可以形成路由实例的路由表。
每个路由实例都有自己的实例名称，并且各自维护一张独立的路由表。
全局路由其实也是一个路由实例，其实例名称为inet.0。
2、普通静态策略路由（只做策略，不作NAT转换）
设置包括如下步骤：
1）设置应用接口子接口，定义为服务区域的入接口/出接口
2）定义路由实例，实例类型为forwarding，实例路由表
3）定义过滤器firewall filter
4）定义接口路由组rib-group；
5）将接口路由组导入到全局路由表及路由实例的路由表中；
6）在内网接口应用过滤器filter
3、做NAT的静态策略路由（既做策略又做NAT转换）
注意：
1）该情况下需要试用virtual-router类型的路由实例
2）每个virtual-router维护一张独立的路由表
配置实例拓扑图
达到目的：
默认内网主机上网走CNC 2M链路访问公网，指定的PC走CNC 50M链路访问外网
实现思路：
默认内网所有主机通过全局路由表inet.0走CNC 2M链路出局访问公网，部分指定的PC通过Juniper SRX的FBF路由策略走路由实例的路由表出局访问公网
设置步骤如下：
1）定义服务区域zone
配置示例：
set security zones security-zone lt host-inbound-traffic system-services all
set security zones security-zone lt host-inbound-traffic protocols all
2）设置应用接口子接口，定义为服务区域的入接口/出接口
配置示例：
set security zones security-zone lt interfaces ge-0/0/2.0 host-inbound-traffic system-services all
set security zones security-zone lt interfaces ge-0/0/2.0 host-inbound-traffic protocols all
3）定义路由实例，路由实例数量可根据接入的ISP线路数量来定义。实例类型为virtual-router，VR的虚拟接口，VR的路由表
配置示例：
set routing-instances CNC50M instance-type virtual-router
set routing-instances CNC50M interface ge-0/0/2.0
set routing-instances CNC50M routing-options static route 0.0.0.0/0 next-hop XX.XX.XX.XX ##指向ISP提供的公网网关
4）定义NAT的相关映射rule-set、rule，策略policy、address-book、application等
√Source NAT的rule-set 配置示例：
set security nat source rule-set CNC50M-snat-internet from zone trust
set security nat source rule-set CNC50M-snat-internet to zone lt
set security nat source rule-set CNC50M-snat-internet rule CNC50M-inside-to-outside match source-address 0.0.0.0/0
set security nat source rule-set CNC50M-snat-internet rule CNC50M-inside-to-outside match destination-address 0.0.0.0/0
set security nat source rule-set CNC50M-snat-internet rule CNC50M-inside-to-outside then source-nat interface
√ 策略policy 配置示例：
set security policies from-zone trust to-zone lt policy CNC50M-snat-internet match source-address CBGZ-out-norestrict
set security policies from-zone trust to-zone lt policy CNC50M-snat-internet match destination-address any
set security policies from-zone trust to-zone lt policy CNC50M-snat-internet match application any
set security policies from-zone trust to-zone lt policy CNC50M-snat-internet then permit
set security policies from-zone trust to-zone lt policy CNC50M-snat-internet then log session-init
set security policies from-zone trust to-zone lt policy CNC50M-snat-internet then log session-close
5）定义过滤器filter
配置示例：
set firewall family inet filter filter-1 term LAN_term from destination-address 172.16.0.0/16
set firewall family inet filter filter-1 term LAN_term from destination-address 172.20.0.0/16
set firewall family inet filter filter-1 term LAN_term from destination-address 192.168.0.0/16
set firewall family inet filter filter-1 term LAN_term then accept ##允许内网PC互访，不作以上配置将会导致网关为此防火墙内网接口的PC无法访问内网其他PC。
##指定的PC从CNC 50M链路出局访问公网
set firewall family inet filter filter-1 term CNC50M_term from source-address 172.16.29.25/32
set firewall family inet filter filter-1 term CNC50M_term from source-address 172.16.29.251/32
set firewall family inet filter filter-1 term CNC50M_term from source-address 172.16.28.166/32
set firewall family inet filter filter-1 term CNC50M_term from source-address 172.16.28.137/32
set firewall family inet filter filter-1 term CNC50M_term from source-address 172.16.28.139/32
set firewall family inet filter filter-1 term CNC50M_term from source-address 172.16.28.138/32
set firewall family inet filter filter-1 term CNC50M_term then routing-instance CNC50M
set firewall family inet filter filter-1 term default then accept ##对于filter的其他数据，采取默认动作accept（接受）
6）定义接口路由组
配置示例：
set routing-options interface-routes rib-group inet INSIDE
7）将接口路由组导入到全局路由表及实例的路由表中
配置示例：
set routing-options rib-groups INSIDE import-rib inet.0
set routing-options rib-groups INSIDE import-rib CNC50M.inet.0
set routing-options rib-groups INSIDE import-rib default.inet.0
8）在内网接口应用相应的过滤器filter
set interfaces ge-0/0/0 unit 0 family inet filter input filter-1
4、普通静态策略路由与NAT转换的策略路由之间的区别
路由实例类型不同：
普通静态策略路由类型：forwarding
NAT转换的策略路由类型：virtual-router
参考链接：http://www.docin.com/p-598358767.html
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