带备注hc bgp路由聚合

BGP路由聚合前言BGP作为一个跨域路由协议，在很多情况下都需要对明细路由进行聚合，并通告到其它远端的AS，而我们将会在本课程中讨论BGP聚合后的路径属性变化情况以及聚合后所引起的问题。Page1培训目标学完本课程后，您应该能：知道BGP路由聚合的方法了解AS_PATH属性的变化知道BGP路由聚合配置知道BGP路由聚合策略Page2目录什么是路由聚合AS_SET改变路由聚合属性Page3目录什么是路由聚合AS_SET改变路由聚合属性Page4路由聚合概述BGP协议可以使用命令，将具体路由聚合成一条聚合路由。192.168.1.16/28192.168.1.32/28192.168.1.48/28路由表192.168.1.16/28192.168.1.32/28192.168.1.48/28192.168.1.0/26路由表192.168.1.0/26Page5Page6路由聚合原则十进制二进制192.168.

11000000.10101000.0001.16

00001.00010000192.168.

11000000.10101000.0001.32

00001.00100000192.168.

11000000.10101000.0001.48

00001.00110000聚合后的路由：192.168.1.0/26BGP路由聚合种类—自动聚合自动聚合对BGP引入的IGP子网路由进行自然掩码聚合。配置自动聚合后，生成聚合后的自然网段路由，而原引入的子网路由被抑制，不会被优选和发布给BGP邻居。192.168.1.1/32192.168.1.2/32192.168.1.3/32RTA[RTA]bgp

100[RTA-bgp]import-route

direct[RTA-bgp]peer

10.1.1.2

as-num

101[RTA-bgp]summary

automaticRTB[RTB]display

bgp

routing-tablePage7Status

codes:

*

-

valid,

>

-

best,

d

-

damped,h

-

history,

i

-

internal,

s

-

suppressed,

S

-

StaleOrigin

:

i

-

IGP,

e

-

EGP,

?

-

pleteNetwork

NextHop

Path/Ogn*>

10.0.0.0

10.1.1.1*>

192.168.1.0

10.1.1.1100?100?AS-100

AS-10110.1.1.110.1.1.2BGP路由聚合种类—手动聚合手动聚合对BGP本地路由进行聚合。通常情况下，手动聚合的优先级高于自动聚合的优先级192.168.1.1/32192.168.1.2/32192.168.1.3/32RTARTBAS-101[RTA]bgp

100[RTA-bgp]network

192.168.1.1

255.255.255.255[RTA-bgp]network

192.168.1.1

255.255.255.255[RTA-bgp]network

192.168.1.1

255.255.255.255[RTA-bgp]peer

10.1.1.2

as-num

101[RTA-bgp]aggregate

192.168.1.0

24

detail-suppressedAS-10010.1.1.1Page810.1.1.2[RTB]display

bgp

routing-tableStatus

codes:

*

-

valid,

>

-

best,

d

-

damped,h

-

history,

i

-

internal,

s

-

suppressed,

S

-

StaleOrigin

:

i

-

IGP,

e-

EGP,

?

-

pleteNetwork

NextHop

Path/Ogn*>

192.168.1.0

10.1.1.1

100iBGP路由聚合需要考虑的问题Page9BGP路由聚合需要考虑的问题明细路由的发布BGP路由属性的继承AS-PathOriginCommunity…

…目录什么是路由聚合AS_SET改变路由聚合属性Page10不带AS_SET的路由聚合AS-100AS-400AS-200RTDAS-300RTCRTARTB160.20.0.0/16160.10.0.0/16aggregate

160.0.0.0

255.0.0.0detail-suppressedPage11AS-100AS-400AS-300AS-200RTDRTCRTARTB160.20.0.0/16160.10.0.0/16不带AS_SET的路由聚合[RTC]

display

bgp

routing-tableStatus

codes:

*

-

valid,

>

-

best,

d

-

damped,h

-

history,

i

-

internal,

s

-

suppressed,

S

-

StaleOrigin

:

i

-

IGP,

e

-

EGP,

?

-

pleteNetwork

NextHop

Path/Ogn*>160.0.0.0/8127.0.0.1is>160.10.0.010.2.2.2200

is>160.20.0.011.1.1.2100

i10.2.2.2Page1211.1.1.2不带AS_SET的路由聚合S-400AAS-300RTCRTD聚合路由160.0.0.0/8被认为是始发于AS-300，并且丢失了所有具体路由160.10.0.0/16

和160.20.0.0/16

的AS-PATH信息。[RTD]

display

bgp

routing-tableStatus

codes:

*

-

valid,

>

-

best,

d

-

damped,h

-

history,

i

-

internal,

s

-

suppressed,

S

-

StaleOrigin

:

i

-

IGP,

e

-

EGP,

?

-

pleteNetwork

NextHop

Path/Ogn*>

160.0.0.0/8

4.4.4.1 300

iPage134.4.4.14.4.4.2带AS_SET的路由聚合AS-100AS-400AS-200RTDAS-300RTCRTB160.20.0.0/16

RTA160.10.0.0/16aggregate

160.0.0.0

255.0.0.0

detail-suppressed

as-setPage14带AS_SET的路由聚合AS-100AS-400AS-300AS-200RTDRTCRTARTB160.20.0.0/16160.10.0.0/16[RTC]

display

bgp

routing-tableStatus

codes:

*

-

valid,

>

-

best,

d

-

damped,h

-

history,

i

-

internal,

s

-

suppressed,

S

-

StaleOrigin

:

i

-

IGP,

e

-

EGP,

?

-

pleteNetwork

NextHop

Path/Ogn*>160.0.0.0/8127.0.0.1{200

100}

is>160.10.0.010.2.2.2200

is>160.20.0.011.1.1.2100

i10.2.2.2Page1511.1.1.2带AS_SET的路由聚合[RTD]

display

bgp

routing-tableStatus

codes:

*

-

valid,

>

-

best,

d

-

damped,h

-

history,

i

-

internal,

s

-

suppressed,

S

-

StaleOrigin

:

i

-

IGP,

e

-

EGP,

?

-

pleteNetwork

NextHop

Path/Ogn*>

160.0.0.0/8

4.4.4.1 300

{200

100}

iAS-400AS-300RTCRTDAS_SET信息在避免路由环路时很重要，因为它记录了被聚合路由所经过的AS。Page16带AS_SET的路由聚合AS-400AS-200RTDAS-300RTCRTARTB160.10.0.0/16Path/Ogn[RTD]

display

bgp

routing-tableNetwork

NextHop*>

160.0.0.0/8

4.4.4.1300

{200}i160.20.0.0/16XAS-100Page17目录什么是路由聚合AS_SET改变路由聚合属性Page18聚合路由的问题Page19聚合路由不继承原有BGP路由属性可以通过命令修改聚合路由属性：aggregate

ip-address

mask

[

as-set

|

attribute-policy

route-policy-name1

|

detail-suppressed

|origin-policyroute-policy-name2

|

suppress-policy

route-policy-name3

]Attribute-PolicyAS-100AS-400AS-200RTDAS-300RTCRTARTB160.20.0.0/16160.10.0.0/16Aggregate

160.0.0.0

255.0.0.0detail-suppressedattribute-policy

att1#route-policy

att1

permit

node

10apply

origin

pletePage20Attribute-PolicyAS-100AS-400AS-300AS-200RTDRTCRTARTB160.20.0.0/16160.10.0.0/16[RTD]

display

bgp

routing-tablePage21Status

codes:

*

-

valid,

>

-

best,

d

-

damped,h

-

history,

i

-

internal,

s

-

suppressed,

S

-

StaleOrigin

:

i

-

IGP,

e

-

EGP,

?

-

pleteNetwork

NextHop

Path/Og