Troubleshooting and Verification 53
that labels get bound to routes in the routing table. What this means is that a non-BGP route arrives in the routing table (the equivalent of an FEC), and a local label gets bound immediately to it. That local label is advertised to an upstream LSR to be used in sending the labeled packet. What this means in layman’s terms is that an LSR will bind a label to an FEC and advertise it to its neighbor without its neighbor having to ask. To provide a little contrast, MPLS in an ATM network uses ordered control with downstream-on-demand.
Troubleshooting and Verification
So far, you’ve been exposed to the basic concepts of frame-mode
MPLS. This section uses a simple network to illustrate device configuration, configuration verification commands, and troubleshooting. For this section, we’ll be using the simple network shown in Figure 2.7.
F I G U R E 2 . 7 A simple network
Serial |
0 |
Serial |
0/1 |
Serial |
0/0 |
Serial |
0/1 |
Serial |
0/0 |
Serial |
0/3 |
Serial |
0/1 |
Serial |
0 |
|
|
|
|
|
|
|
|
||||||||
Peer 1 |
|
Atlanta |
|
|
|
Core |
|
|
Raleigh |
|
|
|
Peer 2 |
||
Routing protocol utilization is illustrated in Figure 2.8.
F I G U R E 2 . 8 Routing protocol utilization
RIPv2
Peer 1 |
Atlanta |
Core |
Raleigh |
Peer 2 |
BGP |
|
|
|
BGP |
AS 65001 |
|
|
|
AS 60002 |
|
|
I-BGP |
|
|
|
|
AS 65000 |
|
|
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54 Chapter 2 Frame-Mode MPLS
The IP addresses of the CE devices in Figures 2.7 and 2.8 (Peer 1 and
Peer 2) are listed in Table 2.11.
T A B L E 2 . 1 1 Customer Addressing
Device |
Loopback 0 |
Serial 0 |
|
|
|
Peer 1 |
192.168.1.1/32 |
192.168.3.5/30 |
Peer 2 |
192.168.2.1/32 |
192.168.3.10/30 |
|
|
|
The IP addresses of the three service provider devices in Figures 2.7 and 2.8 are listed in Table 2.12.
T A B L E |
2 . 1 2 Service Provider Addressing |
|
|
||
|
|
|
|
|
|
|
Device |
Loopback 0 |
Serial 0/0 |
Serial 0/1 |
Serial 0/3 |
|
|
|
|
|
|
|
Atlanta |
204.134.83.1/32 |
204.134.83.5/30 |
192.168.3.6/30 |
N/A |
|
Core |
204.134.83.2/32 |
204.134.83.9/30 |
204.134.83.6/30 |
N/A |
|
Raleigh |
204.134.83.3/32 |
N/A |
192.168.3.9/30 |
204.134.83.10/30 |
|
|
|
|
|
|
Device Configuration
The configurations of the Atlanta POP, Core, Raleigh POP, Peer 1, and
Peer 2 routers are described in the following sections.
Atlanta Router Configuration
The configuration of the Atlanta POP router is as follows:
Atlanta#show running-config
Building configuration...
Current configuration : 1492 bytes
!
version 12.1
service timestamps debug uptime service timestamps log uptime
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Troubleshooting and Verification 55
no service password-encryption
!
hostname Atlanta
!
enable password cisco
!
!
!
!
!
memory-size iomem 25 ip subnet-zero
ip tcp synwait-time 5 no ip domain-lookup
!
ip cef
cns event-service server
!
!
!
!
!
interface Loopback0
ip address 204.134.83.1 255.255.255.255
!
interface Serial0/0
description *** Link to Core Router ***
ip address 204.134.83.5 255.255.255.252 tag-switching ip
no fair-queue clockrate 64000
!
interface Serial0/1
description *** Link to Peer1 ***
ip address 192.168.3.6 255.255.255.252 clockrate 64000
!
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56 Chapter 2 Frame-Mode MPLS
interface Serial0/2 no ip address shutdown
clockrate 64000
!
interface Serial0/3 no ip address shutdown
clockrate 64000
!
interface Ethernet1/0 no ip address shutdown
!
interface Ethernet1/1 no ip address shutdown
!
interface Ethernet1/2 no ip address shutdown
!
interface Ethernet1/3 no ip address shutdown
!
router rip version 2
network 204.134.83.0
!
router bgp 65000
no synchronization
bgp log-neighbor-changes
neighbor 192.168.3.5 remote-as 65001 neighbor 204.134.83.3 remote-as 65000
neighbor 204.134.83.3 update-source Loopback0
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Troubleshooting and Verification 57
neighbor 204.134.83.3 next-hop-self no auto-summary
!
ip classless
no ip http server
!
!
!
line con 0 exec-timeout 0 0 privilege level 15 logging synchronous transport input none
ip netmask-format decimal line aux 0
line vty 0 4 privilege level 15 password cisco logging synchronous login
ip netmask-format decimal
!
end
Core Router Configuration
The configuration of the Core router is as follows:
Core#show running-config
Building configuration...
Current configuration : 1249 bytes
!
version 12.1
service timestamps debug uptime service timestamps log uptime no service password-encryption
!
Copyright ©2002 SYBEX, Inc., Alameda, CA |
www.sybex.com |
58 Chapter 2 Frame-Mode MPLS
hostname Core
!
enable password cisco
!
!
!
!
!
memory-size iomem 25 ip subnet-zero
ip tcp synwait-time 5 no ip domain-lookup
!
ip cef
cns event-service server
!
!
!
!
!
interface Loopback0
ip address 204.134.83.2 255.255.255.255
!
interface Serial0/0
description *** Connection to Raleigh POP ***
ip address 204.134.83.9 255.255.255.252 tag-switching ip
no fair-queue
!
interface Serial0/1
description *** Connection to Atlanta POP ***
ip address 204.134.83.6 255.255.255.252 tag-switching ip
!
interface Serial0/2 no ip address
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Troubleshooting and Verification 59
shutdown
!
interface Serial0/3 no ip address shutdown
!
interface Ethernet1/0 no ip address shutdown
!
interface Ethernet1/1 no ip address shutdown
!
interface Ethernet1/2 no ip address shutdown
!
interface Ethernet1/3 no ip address shutdown
!
router rip version 2
network 204.134.83.0
!
ip classless
no ip http server
!
!
!
line con 0 exec-timeout 0 0 privilege level 15 logging synchronous transport input none
Copyright ©2002 SYBEX, Inc., Alameda, CA |
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60 Chapter 2 Frame-Mode MPLS
ip netmask-format decimal line aux 0
line vty 0 4 privilege level 15 password cisco logging synchronous login
ip netmask-format decimal
!
end
Raleigh Router Configuration
The configuration of the Raleigh POP router is as follows:
Raleigh#show running-config
Building configuration...
Current configuration : 1531 bytes
!
version 12.1
service timestamps debug uptime service timestamps log uptime no service password-encryption
!
hostname Raleigh
!
enable password cisco
!
!
!
!
!
memory-size iomem 25 ip subnet-zero
ip tcp synwait-time 5 no ip domain-lookup
!
Copyright ©2002 SYBEX, Inc., Alameda, CA |
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Troubleshooting and Verification 61
ip cef
cns event-service server
!
!
!
!
!
interface Loopback0
ip address 204.134.83.3 255.255.255.255
!
interface Serial0/0 no ip address shutdown
no fair-queue clockrate 64000
!
interface Serial0/1
description *** Link to Peer2 ***
ip address 192.168.3.9 255.255.255.252 clockrate 64000
!
interface Serial0/2 no ip address shutdown
clockrate 64000
!
interface Serial0/3
description *** Link to Core Router ***
ip address 204.134.83.10 255.255.255.252 tag-switching ip
clockrate 64000
!
interface Ethernet1/0
no ip address shutdown
!
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62 Chapter 2 Frame-Mode MPLS
interface Ethernet1/1 no ip address shutdown
!
interface Ethernet1/2 no ip address shutdown
!
interface Ethernet1/3 no ip address shutdown
!
router rip version 2
network 204.134.83.0
!
router bgp 65000
no synchronization
bgp log-neighbor-changes
neighbor 192.168.3.10 remote-as 65002 neighbor 204.134.83.1 remote-as 65000 neighbor 204.134.83.1 update-source Loopback0 neighbor 204.134.83.1 next-hop-self
no auto-summary
!
ip classless
no ip http server
!
!
!
line con 0 exec-timeout 0 0 privilege level 15 logging synchronous transport input none
ip netmask-format decimal line aux 0
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Troubleshooting and Verification 63
line vty 0 4 privilege level 15 password cisco logging synchronous login
ip netmask-format decimal
!
end
Peer 1 Router Configuration
The configuration of the Peer 1 router is as follows:
Peer1#show running-config
Building configuration...
Current configuration : 914 bytes
!
version 12.1
service timestamps debug uptime service timestamps log uptime no service password-encryption
!
hostname Peer1
!
enable password cisco
!
!
!
!
!
ip subnet-zero
ip tcp synwait-time 5 no ip domain-lookup
!
!
!
!
Copyright ©2002 SYBEX, Inc., Alameda, CA |
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64 Chapter 2 Frame-Mode MPLS
interface Loopback0
ip address 192.168.1.1 255.255.255.255
!
interface Ethernet0 no ip address shutdown
!
interface Serial0
description *** Link to Atlanta POP ***
ip address 192.168.3.5 255.255.255.252 no fair-queue
!
interface Serial1 no ip address shutdown
!
router bgp 65001
no synchronization
bgp log-neighbor-changes redistribute connected
neighbor 192.168.3.6 remote-as 65000 no auto-summary
!
ip classless
no ip http server
!
!
line con 0 exec-timeout 0 0 privilege level 15 logging synchronous transport input none
ip netmask-format decimal line aux 0
line vty 0 4 privilege level 15
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Troubleshooting and Verification 65
password cisco logging synchronous login
ip netmask-format decimal
!
end
Peer 2 Router Configuration
The configuration of the Peer 2 router is as follows:
Peer2#show running-config
Building configuration...
Current configuration : 951 bytes
!
version 12.1
service timestamps debug uptime service timestamps log uptime no service password-encryption
!
hostname Peer2
!
enable password cisco
!
!
!
!
!
ip subnet-zero
ip tcp synwait-time 5 no ip domain-lookup
!
!
!
!
interface Loopback0
ip address 192.168.2.1 255.255.255.255
!
Copyright ©2002 SYBEX, Inc., Alameda, CA |
www.sybex.com |
66 Chapter 2 Frame-Mode MPLS
interface Ethernet0 no ip address shutdown
!
interface Serial0
description *** Link to Raleigh POP ***
ip address 192.168.3.10 255.255.255.252 no fair-queue
!
interface Serial1 no ip address shutdown
!
router bgp 65002
no synchronization
bgp log-neighbor-changes redistribute connected
neighbor 192.168.3.9 remote-as 65000 no auto-summary
!
ip classless
no ip http server
!
!
line con 0 exec-timeout 0 0 privilege level 15 logging synchronous transport input none
ip netmask-format decimal line aux 0
line vty 0 4 privilege level 15 password cisco logging synchronous
Copyright ©2002 SYBEX, Inc., Alameda, CA |
www.sybex.com |