为vEdge或cEdge配置首选默认路由或前缀路由

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已更新: 2022 年 8 月 29 日

文档 ID:218112

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简介

本文档介绍如何配置软件定义的广域网(SD-WAN)控制策略以首选默认路由或前缀。

要求

Cisco 建议您了解以下主题：

思科SD-WAN重叠管理协议(OMP)。
SD-WAN集中控制策略。

使用的组件

本文档中的信息基于以下软件和硬件版本：

Cisco cEdge版本17.3.3
思科vEdge版本20.3.2
思科vSmart控制器版本20.4.2

本文档中的信息都是基于特定实验室环境中的设备编写的。本文档中使用的所有设备最初均采用原始（默认）配置。如果您的网络处于活动状态，请确保您了解所有命令的潜在影响。

背景信息

出于本演示的目的，本实验在不同的端ID上设置5个cEdge/vEdge，其中Router01、Router02和Router03在VPN 1中配置了默认路由。

vSmart system ip 10.1.1.7。
Edge Router01系统ip 10.70.70.1，站点ID 70。
Edge Router02系统ip 10.80.80.1，站点ID 80。
Edge Router03系统ip 10.80.80.2，站点ID 80。
Edge Router04系统ip 10.70.70.2，站点ID 40。
vEdge Router05系统ip 10.20.20.1，站点ID 20。

Router04(10.70.70.2)和Router05(10.20.20.1)从Router01(10.70.70.1)、Router02(10.80.80.1)和Router03(10.80.80.1)接收并安装默认路由。设备没有应用活动的集中式策略或本地化策略，默认情况下为全网状拓扑。

Router04和Router05从三个不同的设备接收默认路由。

Router04# show sdwan omp routes 
Generating output, this might take time, please wait ...
Code:
C   -> chosen
I   -> installed
Red -> redistributed
Rej -> rejected
L   -> looped
R   -> resolved
S   -> stale
Ext -> extranet
Inv -> invalid
Stg -> staged
IA  -> On-demand inactive
U   -> TLOC unresolved
                                            PATH                      ATTRIBUTE                                                       
VPN    PREFIX              FROM PEER        ID     LABEL    STATUS    TYPE       TLOC IP          COLOR            ENCAP  PREFERENCE  
--------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           10.1.1.7          29     1002     C,I,R     installed  10.70.70.1       biz-internet     ipsec  -           
                           10.1.1.7          30     1005     C,I,R     installed  10.80.80.1       mpls             ipsec  -           
                           10.1.1.7          31     1003     C,I,R     installed  10.80.80.2       mpls             ipsec  -

提示：如果show sdwan omp routes路由器收到许多路由，则cEdge的输出可能很大。可以使用 show sdwan omp route vpn 过滤输出，也可以使用过滤show sdwan omp route vpn | s cEdge中前缀的所有扇区输出。

Router05# show omp routes vpn 1
Code:
C   -> chosen
I   -> installed
Red -> redistributed
Rej -> rejected
L   -> looped
R   -> resolved
S   -> stale
Ext -> extranet
Inv -> invalid
Stg -> staged
IA  -> On-demand inactive
U   -> TLOC unresolved

                                            PATH                      ATTRIBUTE                                                       
VPN    PREFIX              FROM PEER        ID     LABEL    STATUS    TYPE       TLOC IP          COLOR            ENCAP  PREFERENCE  
--------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           10.1.1.7          5      1002     C,I,R     installed  10.70.70.1       biz-internet     ipsec  -           
                           10.1.1.7          6      1005     C,I,R     installed  10.80.80.1       mpls             ipsec  -           
                           10.1.1.7          7      1003     C,I,R     installed  10.80.80.2       mpls             ipsec  -

提示：如果show omp route路由器收到太多路由，vEdge的输出可能会很大。可以使用show omp routes vpn ，过滤vEdge中的输出。可以在vEdge| tab 的格式表中使用该命令旁查看输出。

Router04(10.70.70.2)和Router05(10.20.20.1)安装来自Router01(10.70.70.1)、Router02(10.80.80.1)和Router03(10.80.80.1)的default-route。

Router04# show ip route vrf 1 

Routing Table: 1
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area 
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, m - OMP
       n - NAT, Ni - NAT inside, No - NAT outside, Nd - NAT DIA
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       H - NHRP, G - NHRP registered, g - NHRP registration summary
       o - ODR, P - periodic downloaded static route, l - LISP
       a - application route
       + - replicated route, % - next hop override, p - overrides from PfR
       & - replicated local route overrides by connected

Gateway of last resort is 10.80.80.2 to network 0.0.0.0

m*    0.0.0.0/0 [251/0] via 10.80.80.2, 00:05:02, Sdwan-system-intf
                [251/0] via 10.80.80.1, 00:05:02, Sdwan-system-intf
                [251/0] via 10.70.70.1, 00:05:02, Sdwan-system-intf

提示：如果show ip route vrf 路由器收到太多路由，则cEdge的输出可能很大。可以使用show ip route vrf 过滤输出，也可以使用show ip route vrf | s 过滤前缀的所有扇区输出。

Router05# show ip routes vpn 1 0.0.0.0/0
Codes Proto-sub-type:
  IA -> ospf-intra-area, IE -> ospf-inter-area,
  E1 -> ospf-external1, E2 -> ospf-external2,
  N1 -> ospf-nssa-external1, N2 -> ospf-nssa-external2,
  e -> bgp-external, i -> bgp-internal
Codes Status flags:
  F -> fib, S -> selected, I -> inactive,
  B -> blackhole, R -> recursive, L -> import

                                            PROTOCOL  NEXTHOP     NEXTHOP          NEXTHOP                                                   
VPN    PREFIX              PROTOCOL         SUB TYPE  IF NAME     ADDR             VPN      TLOC IP          COLOR            ENCAP  STATUS  
---------------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           omp              -         -           -                -        10.70.70.1       biz-internet     ipsec  F,S     
1      0.0.0.0/0           omp              -         -           -                -        10.80.80.1       mpls             ipsec  F,S     
1      0.0.0.0/0           omp              -         -           -                -        10.80.80.2       mpls             ipsec  F,S

提示：如果show ip routes路由器收到太多路由，vEdge的输出可能会很大。可以使用show ip routes vpn 过滤vEdge中的输出。

配置

解决方案 1：集中控制策略使用，首选来自特定远程路由器Router04上Router01的默认路由

使用拓扑自定义控件并在OMP中应用默认路由的首选项。

使用路由规则而不使用传输位置(TLOC)规则。

匹配条件

匹配在带有0.0.0.0/0前缀的策略列表中预定义的Router01 System-ip 10.70.70.1的发起方选项和Prefix-list。
ip prefix-list 0.0.0.0/0仅匹配default-route并非所有路由，因此您可以将此前缀用于前缀列表。
ip prefix-list 0.0.0.0/0 le 32匹配所有路由。

操作

将此策略应用于出站方向到Router04站点ID 40。

模板策略配置

可以使用vManage GUI配置Centralized Policy的设Control Policy。

在中配置控制Topology策略，可以选择Hub-and-Spoke、Mesh或策Custom Control略。

Custom Control(Route & TLOC) 用于此特定场景，如图所示。

Add Custom Control Topology

Sequence type 和Sequence Rule。
Originator system-ip和前缀列表在匹配条件中设置。

Accept 和Preference针对相同序列的操作进行设置，如图所示。

Custom Control Match Condition

Control Policy 应用于站点40的出站方向，如图所示。

Control Policy Application

警告：要激活Centralized Policy,vSmart需要附加设备模板，或发Centralized Policy送错Failed to activate policy 误。vSmart必须处于vManage模式。

CLI策略配置

您可以手动配置vSmart而不是vManage GUI。

control-policy originatoronly
    sequence 1
     match route
      originator 10.70.70.1
      prefix-list Default_Route
     !
     action accept
      set
       preference 200
      !
     !
    !
  default-action accept
 !
 lists
  prefix-list Default_Route
   ip-prefix 0.0.0.0/0 
  !
  site-list sitio40
   site-id 40 
  !
 !
!
apply-policy
 site-list sitio40
  control-policy originatoronly out <<<<<<<
 !
!

vSmart只从始发者Router01(10.70.70.1)向Router04发送具有更高优先级200的默认路由。

警告：默认操作设置为拒绝。
默认操作可设置为“接受”(accept)或“拒绝”(reject)。

警告：如果序列不匹配，路由将采取默认操作。
这意味着如果默认操作设置为reject且路由与任何序列都不匹配，则会从vSmart中拒绝该路由，并且不会将其通告到重叠。
如果默认操作设置为accept且路由不匹配任何序列，则会从vsmart接受并通告到重叠。

验证

您可以在vSmartshow running-config policy 上使用命令来验证是否正Control-Policy确应用了。

vsmart# show running-config policy control-policy 
policy
 control-policy originatoronly
  sequence 1
   match route
    originator  10.70.70.1
    prefix-list Default_Route
   !
   action accept
    set
     preference 200
    !
   !
  !
  default-action accept
 !
!

用show running-config apply-policy 于检查应用的站点和Control-Policy方向。

vsmart# show running-config apply-policy 
apply-policy
 site-list sitio40
  control-policy originatoronly out
 !
!

提示：如果vSmart有show running-config policy control-policy default-action | sequence 许多控制策略，您可以使用过滤输出。

Router04(10.70.70.2)接收来自Router01(10.70.70.1)、Router02(10.80.80.1)和Router03(10.80.80.1)的所有default-route，但来自Router01的default-route具有较高优先级(200)。

Router04# show sdwan omp routes 
Generating output, this might take time, please wait ...
Code:
C   -> chosen
I   -> installed
Red -> redistributed
Rej -> rejected
L   -> looped
R   -> resolved
S   -> stale
Ext -> extranet
Inv -> invalid
Stg -> staged
IA  -> On-demand inactive
U   -> TLOC unresolved
                                            PATH                      ATTRIBUTE                                                       
VPN    PREFIX              FROM PEER        ID     LABEL    STATUS    TYPE       TLOC IP          COLOR            ENCAP  PREFERENCE  
--------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           10.1.1.7          29     1002     C,I,R     installed  10.70.70.1       biz-internet     ipsec  200   <<<<<<<<<<<<      
                           10.1.1.7          30     1005     R         installed  10.80.80.1       mpls             ipsec  -           
                           10.1.1.7          31     1003     R         installed  10.80.80.2       mpls             ipsec  -

Router04(10.70.70.2)在IP路由表中仅安装来自Router01(10.70.70.1)的路由。

Router04# show ip route vrf 1

Routing Table: 1
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area 
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, m - OMP
       n - NAT, Ni - NAT inside, No - NAT outside, Nd - NAT DIA
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       H - NHRP, G - NHRP registered, g - NHRP registration summary
       o - ODR, P - periodic downloaded static route, l - LISP
       a - application route
       + - replicated route, % - next hop override, p - overrides from PfR
       & - replicated local route overrides by connected

Gateway of last resort is 10.70.70.1 to network 0.0.0.0

m*    0.0.0.0/0 [251/0] via 10.70.70.1, 00:13:25, Sdwan-system-intf

Router05(10.20.20.1)位于站点20，仍然接收并安装来自Router01(10.70.70.1)、Router02(10.80.80.1)和Router03(10.80.80.1)的所有默认路由。

Router05# show omp routes vpn 1
Code:
C   -> chosen
I   -> installed
Red -> redistribute
Rej -> rejected
L   -> looped
R   -> resolved
S   -> stale
Ext -> extranet
Inv -> invalid
Stg -> staged
IA  -> On-demand inactive
U   -> TLOC unresolved

                                            PATH                      ATTRIBUTE                                                       
VPN    PREFIX              FROM PEER        ID     LABEL    STATUS    TYPE       TLOC IP          COLOR            ENCAP  PREFERENCE  
--------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           10.1.1.7          5      1002     C,I,R     installed  10.70.70.1       biz-internet     ipsec  -     <<<<<< no preference      
                           10.1.1.7          6      1005     C,I,R     installed  10.80.80.1       mpls             ipsec  -           
                           10.1.1.7          7      1003     C,I,R     installed  10.80.80.2       mpls             ipsec  -           


Router05# show ip routes vpn 1  
Codes Proto-sub-type:
  IA -> ospf-intra-area, IE -> ospf-inter-area,
  E1 -> ospf-external1, E2 -> ospf-external2,
  N1 -> ospf-nssa-external1, N2 -> ospf-nssa-external2,
  e -> bgp-external, i -> bgp-internal
Codes Status flags:
  F -> fib, S -> selected, I -> inactive,
  B -> blackhole, R -> recursive, L -> import

                                            PROTOCOL  NEXTHOP     NEXTHOP          NEXTHOP                                                   
VPN    PREFIX              PROTOCOL         SUB TYPE  IF NAME     ADDR             VPN      TLOC IP          COLOR            ENCAP  STATUS  
---------------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           omp              -         -           -                -        10.70.70.1       biz-internet     ipsec  F,S     
1      0.0.0.0/0           omp              -         -           -                -        10.80.80.1       mpls             ipsec  F,S     
1      0.0.0.0/0           omp              -         -           -                -        10.80.80.2       mpls             ipsec  F,S

解决方案 2：集中控制策略使用，以首选从路由器01到全网状网中所有路由器的默认路由

使用与使用相同Solution 1的策略，并将其应用于来自Router01站点ID 70的入站方向。

control-policy originatoronly
    sequence 1
     match route
      originator 10.70.70.1
      prefix-list Default_Route
     !
     action accept
      set
       preference 200
      !
     !
    !
  default-action accept
 !
 lists
  prefix-list Default_Route
   ip-prefix 0.0.0.0/0 
  !
  site-list SiteList_70
   site-id 70 
  !
 !
!
apply-policy
 site-list SiteList_70
  control-policy originatoronly in <<<<<<<<<
 !
!

验证

如果使用入站方向，则Router04(10.70.70.2)和Router05(10.20.20.1)只会从Router01(10.70.70.1)接收并安装默认路由。

Router04# show sdwan omp routes 
Generating output, this might take time, please wait ...
Code:
C   -> chosen
I   -> installed
Red -> redistributed
Rej -> rejected
L   -> looped
R   -> resolved
S   -> stale
Ext -> extranet
Inv -> invalid
Stg -> staged
IA  -> On-demand inactive
U   -> TLOC unresolved
                                            PATH                      ATTRIBUTE                                                       
VPN    PREFIX              FROM PEER        ID     LABEL    STATUS    TYPE       TLOC IP          COLOR            ENCAP  PREFERENCE  
--------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           10.1.1.7          29     1002     C,I,R     installed  10.70.70.1       biz-internet     ipsec  200        <<<<<<< 

Router05# show omp routes vpn 1
Code:
C   -> chosen
I   -> installed
Red -> redistributed
Rej -> rejected
L   -> looped
R   -> resolved
S   -> stale
Ext -> extranet
Inv -> invalid
Stg -> staged
IA  -> On-demand inactive
U   -> TLOC unresolved

                                            PATH                      ATTRIBUTE                                                       
VPN    PREFIX              FROM PEER        ID     LABEL    STATUS    TYPE       TLOC IP          COLOR            ENCAP  PREFERENCE  
--------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           10.1.1.7          5      1002     C,I,R     installed  10.70.70.1       biz-internet     ipsec  200         <<<<<<<

两种方案的考虑因素：入站或出站方向

如果丢失Router01(10.70.70.1)，路由器将安装所有没有首选项收到的默认路由。在本场景中，从Router02(10.80.80.1)和Router03(10.80.80.2):

Router04# show sdwan omp routes 
Generating output, this might take time, please wait ...
Code:
C   -> chosen
I   -> installed
Red -> redistributed
Rej -> rejected
L   -> looped
R   -> resolved
S   -> stale
Ext -> extranet
Inv -> invalid
Stg -> staged
IA  -> On-demand inactive
U   -> TLOC unresolved
                                            PATH                      ATTRIBUTE                                                       
VPN    PREFIX              FROM PEER        ID     LABEL    STATUS    TYPE       TLOC IP          COLOR            ENCAP  PREFERENCE  
--------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           10.1.1.7          36     1005     C,I,R     installed  10.80.80.1       mpls             ipsec  -           
                           10.1.1.7          37     1003     C,I,R     installed  10.80.80.2       mpls             ipsec  -           

Router05# show omp routes vpn 1
Code:
C   -> chosen
I   -> installed
Red -> redistributed
Rej -> rejected
L   -> looped
R   -> resolved
S   -> stale
Ext -> extranet
Inv -> invalid
Stg -> staged
IA  -> On-demand inactive
U   -> TLOC unresolved

                                            PATH                      ATTRIBUTE                                                       
VPN    PREFIX              FROM PEER        ID     LABEL    STATUS    TYPE       TLOC IP          COLOR            ENCAP  PREFERENCE  
--------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           10.1.1.7          14     1005     C,I,R     installed  10.80.80.1       mpls             ipsec  -           
                           10.1.1.7          15     1003     C,I,R     installed  10.80.80.2       mpls             ipsec  -

解决方案 3：集中控制策略的使用，以首选来自路由器01的默认路由和来自其他路由器的备用默认路由

Solution 1在此解决方案中，路由器仅从Router01(10.70.70.1)接收默认路由，但是如果丢失默认路由，则您希望远程路由器安装的备用默认路由来自Router02(10.80.80.1)，而不是像和Solution 2中一样来自Router02(10.80.80.1)和Router03(10.80.80.1)。

在同一控制策略上添加一个序列，并应用您从Router01 preference 200的default-route中设置的较低优先级，但比默认优先级(100)高。

对于从Router02(10.80.80.1)通告的默认路由，您可以将优先级设置为150。

control-policy originator
    sequence 1
     match route
      originator 10.70.70.1
      prefix-list Default_Route
     !
     action accept
      set
       preference 200
      !
     !
    !
    sequence 11   <<<<< new sequence
     match route
      originator 10.80.80.1     <<<<< Router02 system ip as originator
      prefix-list Default_Route
     !
     action accept
      set
       preference 150   <<< lower preference of Router01
      !
     !
    !
  default-action accept
 !
 lists
  prefix-list Default_Route
   ip-prefix 0.0.0.0/0 
  !
  site-list sitio40
   site-id 40 
  !
 !
!
apply-policy
 site-list sitio40
  control-policy originator out
 !
!

验证

路由器会收到首选项为200、150和默认首选项的默认路由。

Router04# show sdwa omp routes 
Generating output, this might take time, please wait ...
Code:
C   -> chosen
I   -> installed
Red -> redistributed
Rej -> rejected
L   -> looped
R   -> resolved
S   -> stale
Ext -> extranet
Inv -> invalid
Stg -> staged
IA  -> On-demand inactive
U   -> TLOC unresolved
                                            PATH                      ATTRIBUTE                                                       
VPN    PREFIX              FROM PEER        ID     LABEL    STATUS    TYPE       TLOC IP          COLOR            ENCAP  PREFERENCE  
--------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           10.1.1.7          36     1005     R         installed  10.80.80.1       mpls             ipsec  150   <<<<<<<<      
                           10.1.1.7          37     1003     R         installed  10.80.80.2       mpls             ipsec  -           
                           10.1.1.7          38     1002     C,I,R     installed  10.70.70.1       biz-internet     ipsec  200   <<<<<<<<

Router04(10.70.70.2)仅将来自Router01(10.70.70.1)的默认路由添加到路由表中，并且具有较高的优先级：

Router04# show ip route vrf 1  

Routing Table: 1
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area 
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, m - OMP
       n - NAT, Ni - NAT inside, No - NAT outside, Nd - NAT DIA
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       H - NHRP, G - NHRP registered, g - NHRP registration summary
       o - ODR, P - periodic downloaded static route, l - LISP
       a - application route
       + - replicated route, % - next hop override, p - overrides from PfR
       & - replicated local route overrides by connected

Gateway of last resort is 10.70.70.1 to network 0.0.0.0

m*    0.0.0.0/0 [251/0] via 10.70.70.1, 00:02:47, Sdwan-system-intf

如果丢失Router01(10.70.70.1),Router04(10.70.70.2)只会安装具有下一个更高优先级的路由(来自Router02(10.80.80.1))。

Router04# show sdwa omp routes 
Generating output, this might take time, please wait ...
Code:
C   -> chosen
I   -> installed
Red -> redistributed
Rej -> rejected
L   -> looped
R   -> resolved
S   -> stale
Ext -> extranet
Inv -> invalid
Stg -> staged
IA  -> On-demand inactive
U   -> TLOC unresolved
                                            PATH                      ATTRIBUTE                                                       
VPN    PREFIX              FROM PEER        ID     LABEL    STATUS    TYPE       TLOC IP          COLOR            ENCAP  PREFERENCE  
--------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           10.1.1.7          36     1005     C,I,R     installed  10.80.80.1       mpls             ipsec  150      <<<<<<<   
                           10.1.1.7          37     1003     R         installed  10.80.80.2       mpls             ipsec  -           
Router04# show ip route vrf 1  

Routing Table: 1
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area 
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, m - OMP
       n - NAT, Ni - NAT inside, No - NAT outside, Nd - NAT DIA
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       H - NHRP, G - NHRP registered, g - NHRP registration summary
       o - ODR, P - periodic downloaded static route, l - LISP
       a - application route
       + - replicated route, % - next hop override, p - overrides from PfR
       & - replicated local route overrides by connected

Gateway of last resort is 10.80.80.1 to network 0.0.0.0

m*    0.0.0.0/0 [251/0] via 10.80.80.1, 00:00:15, Sdwan-system-intf

如果丢失Router02,Router04会安装来自Router03(10.80.80.1)的default-route，该路由是具有默认优先级的路由。

提示：入站和出站方向在下一条路径上工作，即入站方向（如果要向全网状网络中的所有远程路由器通告首选项），或出站方向（如果要仅向特定远程站点通告首选项）。

解决方案 4：集中控制策略使用以首选某些前缀路由

如果您使用任何其他前缀而不是默认路由前缀，前面的所有解决方案都完全相同。

前缀为10.40.40.0/24的示例从Router01(10.70.70.1)通告到Router04(10.70.70.2)。

control-policy originator
    sequence 1
     match route
      originator 10.70.70.1
      prefix-list prefix40
     !
     action accept
      set
       preference 200
      !
     !
    !
default-action accept
 !
 lists
  prefix-list prefix40
   ip-prefix 10.40.40.0/24 <<<<<<<<<
  !
  site-list sitio40
   site-id 40 
  !
 !
!
apply-policy
 site-list sitio40
  control-policy originator out
 !
!

验证

Router04# show sdwan omp routes 
Generating output, this might take time, please wait ...
Code:
C   -> chosen
I   -> installed
Red -> redistributed
Rej -> rejected
L   -> looped
R   -> resolved
S   -> stale
Ext -> extranet
Inv -> invalid
Stg -> staged
IA  -> On-demand inactive
U   -> TLOC unresolved
                                            PATH                      ATTRIBUTE                                                       
VPN    PREFIX              FROM PEER        ID     LABEL    STATUS    TYPE       TLOC IP          COLOR            ENCAP  PREFERENCE  
--------------------------------------------------------------------------------------------------------------------------------------
1      0.0.0.0/0           10.1.1.7          36     1005     C,I,R     installed  10.80.80.1       mpls             ipsec  150         
                           10.1.1.7          37     1003     R         installed  10.80.80.2       mpls             ipsec  -          
1      10.40.40.0/24       10.1.1.7          13     1002     C,I,R     installed  10.70.70.1       biz-internet     ipsec  200      <<<<<<<<   
                           10.1.1.7          15     1005     R         installed  10.80.80.1       mpls             ipsec  -           
                           10.1.1.7          16     1003     R         installed  10.80.80.2       mpls             ipsec  -         

Router04# show ip route vrf 1

Routing Table: 1
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area 
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 
       E1 - OSPF external type 1, E2 - OSPF external type 2, m - OMP
       n - NAT, Ni - NAT inside, No - NAT outside, Nd - NAT DIA
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       H - NHRP, G - NHRP registered, g - NHRP registration summary
       o - ODR, P - periodic downloaded static route, l - LISP
       a - application route
       + - replicated route, % - next hop override, p - overrides from PfR
       & - replicated local route overrides by connected

Gateway of last resort is 10.80.80.1 to network 0.0.0.0

m*    0.0.0.0/0 [251/0] via 10.80.80.1, 00:11:55, Sdwan-system-intf 
      10.0.0.0/24 is subnetted, 1 subnets
m        10.40.40.0 [251/0] via 10.70.70.1, 00:02:17, Sdwan-system-intf  <<<<<<
Router04#