HCIP course summary (15)
BGP comprehensive experiment
Claim:
1. Establish topology and assign ip
2. Test
AR11:
AR12:
AR13: Other omissions
;
3. Start the IBGP protocol
AR2:
[r2]ospf 1 router-id 2.2.2.2
[r2-ospf-1]area 0
[r2-ospf-1-area-0.0.0.0]network 172.16.0.0 0.0.255.255
AR3 to AR9, AR11 to AR13, similar, only router-id is different; (omitted)
Lookup table:
Routing table query:
If there is no user network segment, you can use the following command to achieve the goal:
[r2]interface LoopBack 0
[r2-LoopBack1]ospf network-type broadcast
Note: AR2 to AR9 and AR11 to AR13 need to be modified;
4、MPLS
Query neighbors:
5、启动BGP
AR1：
[r1]bgp 1
[r1-bgp]peer 12.1.1.2 as-number 2
[r1-bgp]peer 16.1.1.2 as-number 2
AR2：
bgp 64512
router-id 2.2.2.2
confederation id 2
peer 12.1.1.1 as-number 1
peer 172.16.1.3 as-number 64512
peer 172.16.1.3 connect-interface LoopBack0
peer 172.16.1.6 as-number 64512
peer 172.16.1.6 connect-interface LoopBack0
AR3：
bgp 64512
router-id 3.3.3.3
confederation id 2
peer 172.16.1.2 as-number 64512
peer 172.16.1.2 connect-interface LoopBack0
peer 172.16.1.4 as-number 64512
peer 172.16.1.4 connect-interface LoopBack0
AR4：
bgp 64512
router-id 4.4.4.4
confederation id 2
confederation peer-as 64513
peer 172.16.1.3 as-number 64512
peer 172.16.1.3 connect-interface LoopBack0
peer 172.16.1.5 as-number 64513
peer 172.16.1.5 ebgp-max-hop 255
peer 172.16.1.5 connect-interface LoopBack0
AR5：
bgp 64513
router-id 5.5.5.5
confederation id 2
confederation peer-as 64512
peer 51.1.1.2 as-number 3
peer 172.16.1.4 as-number 64512
peer 172.16.1.4 ebgp-max-hop 255
peer 172.16.1.4 connect-interface LoopBack0
peer 172.16.1.9 as-number 64513
peer 172.16.1.9 connect-interface LoopBack0
AR6：
bgp 64512
router-id 6.6.6.6
confederation id 2
peer 172.16.1.2 as-number 64512
peer 172.16.1.2 connect-interface LoopBack0
peer 172.16.1.7 as-number 64512
peer 172.16.1.7 connect-interface LoopBack0
AR7：
bgp 64512
router-id 7.7.7.7
confederation id 2
peer 172.16.1.6 as-number 64512
peer 172.16.1.6 connect-interface LoopBack0
peer 172.16.1.8 as-number 64512
peer 172.16.1.8 connect-interface LoopBack0
AR8：
bgp 64512
router-id 8.8.8.8
confederation id 2
confederation peer-as 64513
peer 172.16.1.7 as-number 64512
peer 172.16.1.7 connect-interface LoopBack0
peer 172.16.1.9 as-number 64513
peer 172.16.1.9 ebgp-max-hop 255
peer 172.16.1.9 connect-interface LoopBack0
AR9：
bgp 64513
router-id 9.9.9.9
confederation id 2
confederation peer-as 64512
peer 91.1.1.1 as-number 3
peer 91.1.1.2 as-number 3
peer 172.16.1.5 as-number 64513
peer 172.16.1.5 connect-interface LoopBack0
peer 172.16.1.8 as-number 64512
peer 172.16.1.8 ebgp-max-hop 255
peer 172.16.1.8 connect-interface LoopBack0
AR10：
bgp 3
router-id 10.10.10.10
peer 51.1.1.1 as-number 2
peer 91.1.1.1 as-number 2
Lookup table:
6、宣告
AR1：
[r1]bgp 1
[r1-bgp]network 1.1.1.0 24
Check the table: you
can see that AR3 is not good, just modify the next hop:
AR2:
[r2]bgp 64512
[r2-bgp]peer 172.16.1.3 next-hop-local
[r2-bgp]peer 172.16.1.6 next-hop-local
Searched again:
success 
for AR6, the same need to modify the next hop to AR7 preferably:
AR6:
[R6] BGP 64512
[BGP-R6] Use the peer 172.16.1.2 Next-Hop-local
[BGP-R6] Next Use the peer 172.16.1.7 -hop-local
Lookup table:
success
Look up table AR4:
It can be seen that because the ibgp cannot pass routes indirectly, it can be solved by using a reflector:
AR3:
[r3]bgp 64512
[r3-bgp]peer 172.16.1.2 reflect-client
Similarly, the reflector needs to be adjusted on AR7:
AR7:
[r7]bgp 64512
[r7-bgp]peer 172.16.1.8 reflect-client
Lookup table:
success
Check the table again:
AR5:
AR9:
Declaration AR10:
AR10:
[r10] bgp 3
[r10-bgp] network 10.10.10.0 24
For the same reason, AR4 and AR8 are not good, just modify the next hop:
AR5:
[r5]bgp 64513
[r5-bgp]peer 172.16.1.4 next-hop-local
[r5-bgp]peer 172.16.1.9 next-hop -local
AR9：
[r9]bgp 64513
[r9-bgp]peer 172.16.1.5 next-hop-local
[r9-bgp]peer 172.16.1.8 next-hop-local
Lookup table:
In this process, the reflectors at 3 and 7 have only one transmission opportunity. The ibgp interval does not transmit routes to each other, so AR2 and AR6 do not transmit 10.10.10.0 routes to each other;
as shown in the figure:
For backup, let 2 and 6 be reflectors:
AR2:
[r2]bgp 64512
[r2-bgp]peer 172.16.1.6 reflect-client
AR6：
[r6]bgp 64512
[r6-bgp]peer 172.16.1.2 reflect-client
Lookup table:
test:
Check table AR1 again:
It can be seen that the load balance is not reached;
Summary announcement:
——Null interface route announcement:
AR2:
[r2]ip route-static 172.16.0.0 255.255.0.0 NULL 0
[r2-bgp]network 172.16.0.0 16
Lookup table:
AR6：
[r6]ip route-static 172.16.0.0 16 NULL 0
[r6]bgp 64512
[r6-bgp]network 172.16.0.0 16
Lookup table:
At this time, there is a routing problem. You can advertise the required preferred route on the preferred EBGP:
AR2:
[r2]bgp 64512
[r2-bgp]network 172.16.2.0 24
[r2-bgp]network 172.16.3.0 24
[r2- bgp]network 172.16.4.0 24
[r2-bgp]network 172.16.5.0 24
AR6：
r6]bgp 64512
[r6-bgp]network 172.16.6.0 24
[r6-bgp]network 172.16.7.0 24
[r6-bgp]network 172.16.8.0 24
[r6-bgp]network 172.16.9.0 24
Lookup table:
It can be seen that it is not in line with expectations-because 2 and 6 pass routes to each other, the metric of the route passed is greater than the metric of the same route that was cleaned when passed to 1, and vice versa.
Note: It can be announced by transposition-about The routes announced to 2 and announced to 6 exchange announcements;
AR2：
[r2]bgp 64512
[r2-bgp]network 172.16.6.0 24
[r2-bgp]network 172.16.7.0 24
[r2-bgp]network 172.16.8.0 24
[r2-bgp]network 172.16.9.0 24
AR6：
[r6]BGP 64512
[r6-bgp]network 172.16.2.0 24
[r6-bgp]network 172.16.3.0 24
[r6-bgp]network 172.16.4.0 24
[r6-bgp]network 172.16.5.0 24
Lookup table:
success
Continue to declare 11,12,13:
AR2：
[r2]bgp 64512
[r2-bgp]network 172.16.11.0 24
[r2-bgp]network 172.16.12.0 24
[r2-bgp]network 172.16.13.0 24
AR6：
[r6]BGP 64512
[r6-bgp]network 172.16.11.0 24
[r6-bgp]network 172.16.12.0 24
[r6-bgp]network 172.16.13.0 24
Lookup table:
Test AR1ping AR11, 12, 13 (no connection)-11, 12, and 13 have no routes:
AR2:
[r2]ospf 1
[r2-ospf-1] default-route-advertise always
AR6：
[r6]OSPF 1
[r6-ospf-1]default-route-advertise always
AR5：
[r5]ospf 1
[r5-ospf-1]default-route-advertise always
AR9：
[r9]ospf 1
[r9-ospf-1]default-route-advertise always
Lookup table:
test:
Finish on the left
Look up the table on the right: you
can see that all AR5 is selected;
对策：
AR5：
[r5]bgp 64513
[r5-bgp]aggregate 172.16.0.0 255.255.0.0
[r5-bgp]aggregate 172.16.0.0 255.255.0.0 detail-suppressed
AR9:
[r9]bgp 64513
[r9-bgp]aggregate 172.16.0.0 255.255.0.0
[r9-bgp]aggregate 172.16.0.0 255.255.0.0 detail-suppressed (default suppression)
In this way, only the summary will be passed to AR10;
Lookup table:
Use prefix list:
AR5:
[r5]ip ip-prefix aa deny 172.16.6.0 24 (reject)
[r5]ip ip-prefix aa deny 172.16.7.0 24
[r5]ip ip-prefix aa deny 172.16.8.0 24
[r5]ip ip-prefix aa deny 172.16.9.0 24
[r5]ip ip-prefix aa permit 0.0.0.0 0 less-equal 32 (allow all)
[r5]bgp 64513
[r5-bgp]undo aggregate 172.16.0.0 255.255.0.0 detail-suppressed
[r5-bgp]aggregate 172.16.0.0 255.255.0.0
[r5-bgp]peer 51.1.1.2 ip-prefix aa export
AR9：
[r9]ip ip-prefix aa deny 172.16.2.0 24
[r9]ip ip-prefix aa deny 172.16.3.0 24
[r9]ip ip-prefix aa deny 172.16.4.0 24
[r9]ip ip-prefix aa deny 172.16.5.0 24
[r9]ip ip-prefix aa permit 0.0.0.0 0 less-equal 32
[r9]bgp 64513
[r9-bgp]undo aggregate 172.16.0.0 255.255.0.0 detail-suppressed
[r9-bgp]aggregate 172.16.0.0 255.255.0.0
[r9-bgp]peer 91.1.1.2 ip-prefix aa export
Lookup table:
success
7. Load balancing
AR1:
[r1]bgp 1
[r1-bgp]maximum load-balancing ebgp 2 (the maximum number of load paths)
AR10：
[r10]bgp 3
[r10-bgp]maximum load-balancing ebgp 2
test:
Experiment completed