基于SR-TE policy 配置SR-TE
SR-TE policy --真机
一、topo
需求：
1、默认情况下R1访问R4通过矢量路由协议OSPF/ISIS的SPF算法走最优路径：R1-R6-R4
2、通过segment routing段路由严格控路让R1-R4走R1-R2-R4-R6这条链路互访
二、SR-BE配置步骤
1、基础连通性配置
1)命名、关闭DCN、PNP（以R1为例）
[HUAWEI]sysname R1
[R1]undo dcn
[R1]undo pnp enable
2）互联接口，回环口配置IP地址（以R1为例）
[R1-GigabitEthernet0/5/0]int g0/5/1
[R1-GigabitEthernet0/5/0]ip add 10.1.16.1 24
[R1-GigabitEthernet0/5/0]int g0/5/1
[R1-GigabitEthernet0/5/1]ip add 10.1.12.1 24
[R1-GigabitEthernet0/5/1]int lo0
[R1-LoopBack0]ip add 10.1.1.1 32
连通性测试：
[R6-LoopBack0]ping 10.1.16.1
PING 10.1.16.1: 56 data bytes, press CTRL_C to break
Reply from 10.1.16.1: bytes=56 Sequence=1 ttl=255 time=1 ms
Reply from 10.1.16.1: bytes=56 Sequence=2 ttl=255 time=1 ms
Reply from 10.1.16.1: bytes=56 Sequence=3 ttl=255 time=1 ms
Reply from 10.1.16.1: bytes=56 Sequence=4 ttl=255 time=1 ms
Reply from 10.1.16.1: bytes=56 Sequence=5 ttl=255 time=2 ms
--- 10.1.16.1 ping statistics ---
5 packet(s) transmitted
5 packet(s) received
0.00% packet loss
round-trip min/avg/max = 1/1/2 ms
[R6-LoopBack0]ping 10.1.46.4
PING 10.1.46.4: 56 data bytes, press CTRL_C to break
Reply from 10.1.46.4: bytes=56 Sequence=1 ttl=255 time=1 ms
Reply from 10.1.46.4: bytes=56 Sequence=2 ttl=255 time=1 ms
Reply from 10.1.46.4: bytes=56 Sequence=3 ttl=255 time=1 ms
Reply from 10.1.46.4: bytes=56 Sequence=4 ttl=255 time=1 ms
Reply from 10.1.46.4: bytes=56 Sequence=5 ttl=255 time=1 ms
--- 10.1.46.4 ping statistics ---
5 packet(s) transmitted
5 packet(s) received
0.00% packet loss
round-trip min/avg/max = 1/1/1 ms
2、core igp配置（以R1为例）
1）OSPF
ospf 1 router-id 1.1.1.1
area 0.0.0.0
network 10.1.1.1 0.0.0.0
network 10.1.12.1 0.0.0.0
network 10.1.16.1 0.0.0.0
验证：
[R1]display ip routing-table protocol ospf
Route Flags: R - relay, D - download to fib, T - to -instance, B - black hole route
------------------------------------------------------------------------------
_public_ Routing Table : OSPF
Destinations : 10 Routes : 11
OSPF routing table status :
Destinations : 7 Routes : 8
Destination/Mask Proto Pre Cost Flags NextHop Interface
10.1.2.2/32 OSPF 10 1 D 10.1.12.2 GigabitEthernet0/5/1
10.1.3.3/32 OSPF 10 2 D 10.1.12.2 GigabitEthernet0/5/1
10.1.4.4/32 OSPF 10 2 D 10.1.16.6 GigabitEthernet0/5/0
10.1.6.6/32 OSPF 10 1 D 10.1.16.6 GigabitEthernet0/5/0
10.1.23.0/24 OSPF 10 2 D 10.1.12.2 GigabitEthernet0/5/1
10.1.34.0/24 OSPF 10 3 D 10.1.12.2 GigabitEthernet0/5/1
OSPF 10 3 D 10.1.16.6 GigabitEthernet0/5/0
10.1.46.0/24 OSPF 10 2 D 10.1.16.6 GigabitEthernet0/5/0
OSPF routing table status :
Destinations : 3 Routes : 3
Destination/Mask Proto Pre Cost Flags NextHop Interface
10.1.1.1/32 OSPF 10 0 10.1.1.1 LoopBack0
10.1.12.0/24 OSPF 10 1 10.1.12.1 GigabitEthernet0/5/1
10.1.16.0/24 OSPF 10 1 10.1.16.1 GigabitEthernet0/5/0
2）ISIS
a.全局使能ISIS
isis 1
is-level level-2
cost-style wide
network-entity 49.0001.0000.0000.0001.00
is-name R1
b.接口使能ISIS
[R1]int g0/5/1
[R1-GigabitEthernet0/5/1]isis en
[R1-GigabitEthernet0/5/1]int g0/5/0
[R1-GigabitEthernet0/5/0]isis en
[R1-GigabitEthernet0/5/0]int lo0
[R1-LoopBack0]isis en
验证：
[R1]dis isis route
Route information for ISIS(1)
-----------------------------
ISIS(1) Level-2 Forwarding Table
--------------------------------
IPV4 Destination IntCost ExtCost ExitInterface NextHop Flags
-------------------------------------------------------------------------------
10.1.1.1/32 0 NULL Loop0 Direct D/-/L/-
10.1.2.2/32 10 NULL GE0/5/1 10.1.12.2 A/-/-/-
10.1.3.3/32 20 NULL GE0/5/1 10.1.12.2 A/-/-/-
10.1.4.4/32 20 NULL GE0/5/0 10.1.16.6 A/-/-/-
10.1.6.6/32 10 NULL GE0/5/0 10.1.16.6 A/-/-/-
10.1.12.0/24 10 NULL GE0/5/1 Direct D/-/L/-
10.1.16.0/24 10 NULL GE0/5/0 Direct D/-/L/-
10.1.23.0/24 20 NULL GE0/5/1 10.1.12.2 A/-/-/-
10.1.34.0/24 30 NULL GE0/5/1 10.1.12.2 A/-/-/-
GE0/5/0 10.1.16.6
10.1.46.0/24 20 NULL GE0/5/0 10.1.16.6 A/-/-/-
Flags: D-Direct, A-Added to URT, L-Advertised in LSPs, S-IGP Shortcut,
U-Up/Down Bit Set, LP-Local Prefix-Sid
Protect Type: L-Link Protect, N-Node Protect
3、使能MPLS（以R1为例）
全局使能
[R1]mpls lsr-id 10.1.1.1
[R1]mpls
4、使能SR（以R1为例）
1）全局使能SR
[R1]segment-routing
2）IGP使能SR
a.OSPF
ospf 1
opaque-capability enable
segment-routing mpls
segment-routing global-block 16100 16199
b.ISIS
isis 1
segment-routing mpls
segment-routing global-block 16100 16199
3）回环接口使能prefix sid
[R1]interface LoopBack 0
[R1-LoopBack0]ospf prefix-sid index 1
验证：
[R1]dis segment-routing prefix mpls forwarding
Segment Routing Prefix MPLS Forwarding Information
--------------------------------------------------------------
Role : I-Ingress, T-Transit, E-Egress, I&T-Ingress And Transit
Prefix Label OutLabel Interface NextHop Role MPLSMtu Mtu State
-----------------------------------------------------------------------------------------------------------------
10.1.1.1/32 16101 NULL Loop0 127.0.0.1 E --- 1500 Active
10.1.2.2/32 16102 16202 GE0/5/1 10.1.12.2 I&T --- 1500 Active
10.1.3.3/32 16103 16203 GE0/5/1 10.1.12.2 I&T --- 1500 Active
10.1.4.4/32 16104 16604 GE0/5/0 10.1.16.6 I&T --- 1500 Active
10.1.6.6/32 16106 16606 GE0/5/0 10.1.16.6 I&T --- 1500 Active
Total information(s): 5
4）配置adjacency sid
思路：
R1:
segment-routing
ipv4 adjacency local-ip-addr 10.1.12.1 remote-ip-addr 10.1.12.2 sid 147012
ipv4 adjacency local-ip-addr 10.1.16.1 remote-ip-addr 10.1.16.6 sid 147016
#
R2:
segment-routing
ipv4 adjacency local-ip-addr 10.1.12.2 remote-ip-addr 10.1.12.1 sid 147021
ipv4 adjacency local-ip-addr 10.1.23.2 remote-ip-addr 10.1.23.3 sid 147023
#
R3:
segment-routing
ipv4 adjacency local-ip-addr 10.1.23.3 remote-ip-addr 10.1.23.2 sid 147032
ipv4 adjacency local-ip-addr 10.1.34.3 remote-ip-addr 10.1.34.4 sid 147034
#
R4:
segment-routing
ipv4 adjacency local-ip-addr 10.1.34.4 remote-ip-addr 10.1.34.3 sid 147043
ipv4 adjacency local-ip-addr 10.1.46.4 remote-ip-addr 10.1.46.6 sid 147046
#
R6:
segment-routing
ipv4 adjacency local-ip-addr 10.1.46.6 remote-ip-addr 10.1.46.4 sid 147064
ipv4 adjacency local-ip-addr 10.1.16.6 remote-ip-addr 10.1.16.1 sid 147061
验证：
[R1]DIS segment-routing adjacency mpls forwarding
Segment Routing Adjacency MPLS Forwarding Information
Label Interface NextHop Type MPLSMtu Mtu
-----------------------------------------------------------------------------
2108 GE0/5/0 10.1.16.6 OSPFv2 --- 1500
2109 GE0/5/1 10.1.12.2 OSPFv2 --- 1500
2140 GE0/5/0 10.1.16.6 ISIS-V4 --- 1500
2141 GE0/5/1 10.1.12.2 ISIS-V4 --- 1500
147012 GE0/5/1 10.1.12.2 STATIC-V4 --- 1500
147016 GE0/5/0 10.1.16.6 STATIC-V4 --- 1500
Total information(s):
三、SR-TE policy 配置
1）配置segment-list
R1:
segment-list toR4
index 10 sid label 147012
index 20 sid label 147023
index 30 sid label 147034
R4:
segment-list toR1
index 10 sid label 147043
index 20 sid label 147032
index 30 sid label 147021
2)配置SR-TE policy
R1:
sr-te policy A endpoint 10.1.4.4 color 100
candidate-path preference 200
segment-list toR4
R4:
sr-te policy A endpoint 10.1.1.1 color 100
candidate-path preference 200
segment-list toR1
验证：
[R1]dis sr-te policy policy-name A
PolicyName : A
Endpoint : 10.1.4.4 Color : 100
TunnelId : 1 TunnelType : SR-TE Policy
Binding SID : - MTU : -
Policy State : Up State Change Time : 2022-07-20 02:39:27
Admin State : UP Traffic Statistics : Disable
BFD : Disable Backup Hot-Standby : Disable
DiffServ-Mode : -
Candidate-path Count : 1
Candidate-path Preference: 200
Path State : Active Path Type : Primary
Protocol-Origin : Configuration(30) Originator : 0, 0.0.0.0
Discriminator : 200 Binding SID : -
GroupId : 1 Policy Name : A
Template ID : -
Segment-List Count : 1
Segment-List : toR4
Segment-List ID : 1 XcIndex : 2000001
List State : Up BFD State : -
EXP : - TTL : -
DeleteTimerRemain : -
Label : 147012, 147023, 147034
[R4]dis sr-te policy policy-name A
PolicyName : A
Endpoint : 10.1.1.1 Color : 100
TunnelId : 8193 TunnelType : SR-TE Policy
Binding SID : - MTU : -
Policy State : Up State Change Time : 2022-07-20 02:47:26
Admin State : UP Traffic Statistics : Disable
BFD : Disable Backup Hot-Standby : Disable
DiffServ-Mode : -
Candidate-path Count : 1
Candidate-path Preference: 200
Path State : Active Path Type : Primary
Protocol-Origin : Configuration(30) Originator : 0, 0.0.0.0
Discriminator : 200 Binding SID : -
GroupId : 8193 Policy Name : A
Template ID : -
Segment-List Count : 1
Segment-List : toR1
Segment-List ID : 8193 XcIndex : 2008193
List State : Up BFD State : -
EXP : - TTL : -
DeleteTimerRemain : -
Label : 147043, 147032, 147021
四、流量导入
1、ipv4 bgp over SR-TE policy
1）创建tunnel policy
R1:
tunnel-policy toR4
tunnel select-seq sr-te-policy load-balance-number 2 unmix
R4:
tunnel-policy toR1
tunnel select-seq sr-te-policy load-balance-number 2 unmix
2）迭代隧道调用tunnel policy
R1:
route recursive-lookup tunnel tunnel-policy toR4
R4:
route recursive-lookup tunnel tunnel-policy toR1
3)配置颜色
a.R1和R4建立IBGP邻居关系
bgp 234
router-id 1.1.1.1
peer 10.1.4.4 as-number 234
peer 10.1.4.4 connect-interface LoopBack0
验证：
[R4-bgp]dis bgp peer
BGP local router ID : 4.4.4.4
Local AS number : 234
Total number of peers : 1 Peers in established state : 1
Peer V AS MsgRcvd MsgSent OutQ Up/Down State PrefRcv
10.1.1.1 4 234 4 4 0 00:00:22 Established 1
a.创建route-policy
route-policy color permit node 10
apply extcommunity color 0:100
c.向peer通告扩展community属性，通告loopback 带上route-policy
R1:
BGP 234
peer 10.1.4.4 advertise-ext-community
net 10.1.11.11 route-policy color
R4:
BGP 234
peer 10.1.1.1 advertise-ext-community
net 10.1.44.44 route-policy color
验证：
[R1-bgp]dis bgp routing-table 10.1.44.44
BGP local router ID : 1.1.1.1
Local AS number : 234
Paths: 1 available, 1 best, 1 select, 0 best-external, 0 add-path
BGP routing table entry information of 10.1.44.44/32:
From: 10.1.4.4 (4.4.4.4)
Route Duration: 0d00h00m21s
Relay IP Nexthop: 10.1.16.6
Relay IP Out-Interface: GigabitEthernet0/5/0
Relay Tunnel Out-Interface: A
Original nexthop: 10.1.4.4
Qos information : 0x0
Ext-Community: Color <0 : 100>
AS-path Nil, origin igp, MED 0, localpref 100, pref-val 0, valid, internal, best, select, pre 255
Not advertised to any peer yet
[R4-bgp]dis bgp routing-table 10.1.44.44
BGP local router ID : 4.4.4.4
Local AS number : 234
Paths: 1 available, 1 best, 1 select, 0 best-external, 0 add-path
BGP routing table entry information of 10.1.44.44/32:
Network route.
From: 0.0.0.0 (0.0.0.0)
Route Duration: 0d00h01m09s
Direct Out-interface: LoopBack1
Original nexthop: 127.0.0.1
Qos information : 0x0
Ext-Community: Color <0 : 100>
AS-path Nil, origin igp, MED 0, pref-val 0, valid, local, best, select, pre 0
Advertised to such 1 peers:
10.1.1.1
[R1]dis ip routing-table 10.1.44.44
Route Flags: R - relay, D - download to fib, T - to -instance, B - black hole route
------------------------------------------------------------------------------
Routing Table : _public_
Summary Count : 1
Destination/Mask Proto Pre Cost Flags NextHop Interface
10.1.44.44/32 IBGP 255 0 RD 10.1.4.4 A
五、结果测试
[R1]tracert -v -a 10.1.11.11 10.1.44.44
traceroute to 10.1.44.44(10.1.44.44), max hops: 30, packet length: 40, press CTRL_C to break
1 10.1.12.2[MPLS Label=147023/147034 Exp=0/0 S=0/1 TTL=1/1] 4 ms 3 ms 3 ms
2 * * *
3 10.1.44.44 3 ms 2 ms 3 ms
[R1]dis ip routing-table 10.1.44.44 verbose
Route Flags: R - relay, D - download to fib, T - to -instance, B - black hole route
------------------------------------------------------------------------------
Routing Table : _public_
Summary Count : 1
Destination: 10.1.44.44/32
Protocol: IBGP Process ID: 0
Preference: 255 Cost: 0
NextHop: 10.1.4.4 Neighbour: 10.1.4.4
State: Active Adv Relied Age: 00h05m57s
Tag: 0 Priority: low
Label: NULL QoSInfo: 0x0
IndirectID: 0x10000F7 Instance:
RelayNextHop: 0.0.0.0 Interface: A
TunnelID: 0x000000003200000001 Flags: RD
[R1]dis fib slot 7 10.1.44.44
Route Entry Count: 1
Destination/Mask Nexthop Flag TimeStamp Interface TunnelID
10.1.44.44/32 10.1.4.4 DGU 03:46:23 A 0x000000003200000001
QoSInfo: 0x0
IndirectID: 0x10000F7 Instance:
RelayNextHop: 0.0.0.0 Interface: A
TunnelID: 0x000000003200000001 Flags: RD
[R1]dis fib slot 7 10.1.44.44
Route Entry Count: 1
Destination/Mask Nexthop Flag TimeStamp Interface TunnelID
10.1.44.44/32 10.1.4.4 DGU 03:46:23 A 0x000000003200000001