Lab - Config ure and Veri Verify fy eBGP eBGP Topology
Addr Ad dr essin ess in g Table Tab le Device R1 R2 ISP-1
Interf ace
IP Addr ess
Subnet Mask
S0/0/1
198.133.219.1
255.255.255.248
S0/0/0
198.133.219.2
255.255.255.248
S0/0/1 (DCE)
209.165.200.2
255.255.255.252
S0/0/1
209.165.200.1
255.255.255.252
10.10.10.10
255.255.255.255
Web Server
Objectives Part Part 1: Bu ild th e Network Network and Confi gure Basic Device Settin Settin gs Part 2: Configure eBGP on R1 Part Part 3: Verify Verify eBGP Configur ation
Backgroun d / Scenario Scenario In this lab you will configure eBGP for the Company. The ISP will provide the default route to the Internet. Once configuration is complete you will use various show commands show commands to verify that the eBGP configuration is working as expected.
Required Resources •
3 Routers (Cisco 1941 with Cisco IOS Release 15.2(4)M3 universal image or comparable)
•
Console cables to configure the Cisco IOS devices devices via the console ports
•
Serial cables as shown in the topology
© 2016 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public.
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Lab – Configur e and Verify eBGP
Part 1: Buil d the Network and Confi gure Basic Device Settings In Part 1, you will set up the network topology and configure basic settings on R1 and R2 routers. You will also copy the provided configuration for ISP-1 on to that router.
Step 1: Cable the network as shown in the topolog y. Step 2: Initi alize and reload the networ k devic es as necessary. Step 3: Confi gur e basic settin gs on R1 and R2. a.
Disable DNS lookup to prevent the routers from attempting to translate incorrectly entered commands as though they were host names.
b.
Configure the hostnames according to the topology.
c.
Configure interfaces according to the Addressing Table.
d.
Save the running configuration to the startup configuration file.
Step 4: Copy conf igu ratio n to ISP-1. Copy and paste the following configuration to ISP-1. host name I SP- 1 no i p domai n- l ookup i nt erf ace Loopback0 i p addr ess 10. 10. 10. 10 255. 255. 255. 255 i nt er f ace Ser i al 0/ 0/ 1 i p addr ess 209. 165. 200. 1 255. 255. 255. 252 no shut i p r out e 0. 0. 0. 0 0. 0. 0. 0 l o0 r out er bgp 65001 bgp l og- nei ghbor - changes net work 0. 0. 0. 0 nei ghbor 209. 165. 200. 2 r emot e- as 65000 end
Part 2: Configure eBGP on R2 Configure R2 to become an eBGP peer with ISP-1. Refer to the Topology for BGP AS number information.
Step 1: Enable BGP and identi fy the AS numb er for the Comp any. R2( conf i g) # router bgp 65000
Step 2: Use the neighbor com mand to identif y ISP-1 as the BGP peer. R2( conf i g- r out er ) # neighbor 209.165.200.1 remote-as 65001
Step 3: Add the Comp any’s networ k to the BGP table so it is adverti sed to ISP-1. R2( conf i g- r out er ) # network 198.133.219.0 mask 255.255.255.248
© 2016 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public.
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Lab – Configur e and Verify eBGP
Part 3: Verif y eBGP Config urati on In Part 3, use the BGP verifications commands to verify that the BGP configuration is working as expected.
Step 1: Displ ay the IPv4 rou ting table on R2. R2# show ip route Codes: L - l ocal , C - connected, S - st at i c, R - RI P, M - mobi l e, B - BGP D - EI GRP, EX - EI GRP ext ernal , O - OSPF, I A - OSPF i nt er ar ea N1 - OSPF NSSA ext er nal t ype 1, N2 - OSPF NSSA ext er nal t ype 2 E1 - OSPF ext er nal t ype 1, E2 - OSPF ext er nal t ype 2 i - I S- I S, s u - I S- I S s ummar y , L 1 - I S- I S l evel - 1, L 2 - I S- I S l evel - 2 i a - I S- I S i nt er area, * - candi dat e def aul t , U - per- user st at i c rout e o - ODR, P - peri odi c downl oaded st ati c r out e, H - NHRP, l - LI SP a - appl i cat i on r out e + - r epl i cat ed r out e, % - next hop over r i de Gat eway of l ast r esor t i s 209. 165. 200. 1 t o net work 0. 0. 0. 0 B* C L
0. 0. 0. 0/ 0 [ 20/ 0] vi a 209. 165. 200. 1, 00: 00: 07 198. 133. 219. 0/ 24 i s vari abl y subnet t ed, 2 subnet s, 2 masks 198. 133. 219. 0/ 29 i s di r ect l y connect ed, Seri al 0/ 0/ 0
C
198. 133. 219. 2/ 32 i s di r ect l y connect ed, Ser i al 0/ 0/ 0 209. 165. 200. 0/ 24 i s vari abl y subnet t ed, 2 subnet s, 2 masks 209. 165. 200. 0/ 30 i s di r ect l y connect ed, Seri al 0/ 0/ 1
L
209. 165. 200. 2/ 32 i s di r ect l y connect ed, Ser i al 0/ 0/ 1
Step 2: Displ ay the BGP table on R2. R2# show ip bgp BGP t abl e ver si on i s 4, l ocal r out er I D i s 209. 165. 200. 2 St at us codes: s suppr essed, d damped, h hi st or y, * val i d, > best , i - i nt er nal , r RI B- f ai l ur e , S St al e, m mul t i pat h, b bac kup- pat h, f RT- Fi l t er , x best - external , a addi t i onal - pat h, c RI B- compr essed, Or i gi n codes: i - I GP, e - EGP, ? - i ncompl et e RPKI val i dat i on codes: V val i d, I i nval i d, N Not f ound
*> *>
Net wor k Next Hop 0. 0. 0. 0 209. 165. 200. 1 198. 133. 219. 0/ 29 0. 0. 0. 0
Met r i c LocPr f Wei ght Pat h 0 0 65001 i 0 32768 i
Step 3: Displ ay the BGP conn ectio n status on R2. R2# show ip bgp summary BGP r out er i dent i f i er 209. 165. 200. 2, l ocal AS number 65000 BGP t abl e versi on i s 4, mai n r out i ng t abl e ver si on 4 2 net wor k ent r i es usi ng 288 byt es of memor y 2 pat h ent r i es usi ng 160 byt es of memor y 2/ 2 BGP pat h/ best pat h at t r i but e ent r i es usi ng 320 byt es of memor y 1 BGP AS- PATH ent r i es usi ng 24 byt es of memor y 0 BGP r out e- map cache ent r i es usi ng 0 byt es of memor y
© 2016 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public.
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Lab – Configur e and Verify eBGP 0 BGP f i l t er - l i st cache ent r i es usi ng 0 byt es of memory BGP usi ng 792 t ot al byt es of memor y BGP act i vi t y 2/ 0 pr ef i xes, 2/ 0 pat hs, scan i nt er val 60 secs Nei ghbor St ate/ Pf xRcd 209. 165. 200. 1
V 4
AS MsgRcvd MsgSent 65001
12
Tbl Ver
11
I nQ Out Q Up/ Down
4
0
0 00: 06: 56
1
Step 4: Displ ay the IPv4 rou ting table on ISP-1. Verify that the 198.133.218.0/29 network is being advertised to the ISP-1 router.
I SP- 1# show ip route Codes: L - l ocal , C - connected, S - st at i c, R - RI P, M - mobi l e, B - BGP D - EI GRP, EX - EI GRP ext ernal , O - OSPF, I A - OSPF i nt er ar ea N1 - OSPF NSSA ext er nal t ype 1, N2 - OSPF NSSA ext er nal t ype 2 E1 - OSPF ext er nal t ype 1, E2 - OSPF ext er nal t ype 2 i - I S- I S, s u - I S- I S s ummar y , L 1 - I S- I S l evel - 1, L 2 - I S- I S l evel - 2 i a - I S- I S i nt er area, * - candi dat e def aul t , U - per- user st at i c rout e o - ODR, P - peri odi c downl oaded st ati c r out e, H - NHRP, l - LI SP a - appl i cat i on r out e + - r epl i cat ed r out e, % - next hop over r i de Gat eway of l ast r esor t i s 0. 0. 0. 0 t o net wor k 0. 0. 0. 0 S*
B
0. 0. 0. 0/ 0 i s di r ect l y connect ed, Loopback0 10. 0. 0. 0/ 32 i s subnet t ed, 1 subnets 10. 10. 10. 10 i s di r ect l y connect ed, Loopback0 198. 133. 219. 0/ 29 i s subnet t ed, 1 subnet s 198. 133. 219. 0 [ 20/ 0] vi a 209. 165. 200. 2, 00: 00: 25
C L
209. 165. 200. 0/ 24 i s vari abl y subnet t ed, 2 subnet s, 2 masks 209. 165. 200. 0/ 30 i s di r ect l y connect ed, Seri al 0/ 0/ 1 209. 165. 200. 1/ 32 i s di r ect l y connect ed, Ser i al 0/ 0/ 1
C
Ping the Web Server from R1. Were the pings successful?
Reflection The topology used in this lab was created to demonstrate how to configure the BGP routing protocol. However, the BGP protocol would not normally be configured for a topology like this in the real world. Why?
© 2016 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public.
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Lab – Configur e and Verify eBGP
Router Interface Summary Table Router Interface Summary Router Model
Ethernet Interf ace #1
Ethernet Interf ace #2
Serial Interf ace #1
Serial Interf ace #2
1800
Fast Ethernet 0/0 (F0/0)
Fast Ethernet 0/1 (F0/1)
Serial 0/0/0 (S0/0/0)
Serial 0/0/1 (S0/0/1)
1900
Gigabit Ethernet 0/0 (G0/0)
Gigabit Ethernet 0/1 (G0/1)
Serial 0/0/0 (S0/0/0)
Serial 0/0/1 (S0/0/1)
2801
Fast Ethernet 0/0 (F0/0)
Fast Ethernet 0/1 (F0/1)
Serial 0/1/0 (S0/1/0)
Serial 0/1/1 (S0/1/1)
2811
Fast Ethernet 0/0 (F0/0)
Fast Ethernet 0/1 (F0/1)
Serial 0/0/0 (S0/0/0)
Serial 0/0/1 (S0/0/1)
2900
Gigabit Ethernet 0/0 (G0/0)
Gigabit Ethernet 0/1 (G0/1)
Serial 0/0/0 (S0/0/0)
Serial 0/0/1 (S0/0/1)
Note: To find out how the router is configured, look at the interfaces to identify the type of router and how many interfaces the router has. There is no way to effectively list all the combinations of configurations for each router class. This table includes identifiers for the possible combinations of Ethernet and Serial interfaces in the device. The table does not include any other type of interface, even though a specific router may contain one. An example of this might be an ISDN BRI interface. The string in parenthesis is the legal abbreviation that can be used in Cisco IOS commands to represent the interface.
© 2016 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public.
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