MPLS FastReRouting

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MPLS T.E. FastReRouting Fast Convergence In laboratorio si è voluto provare sia la funzionalità di MPLS T.E. FastReRouting che di IP FastRerouting allo scopo di verificarne sia gli impatti che i tempi di convergenza in caso di failure. Per quanto concerne l’MPLS T.E. F.R.R sono stati realizzati diversi tunnel MPLS in modo da realizzare una magliatura MPLS tra i vari nodi PE. Lo scopo è quello di creare e rendere disponibili percorsi LDP alternativi in modo da accelerare la convergenza in caso di caduta di uno dei link di backbone. Di seguito un estratto della configurazione utilizzata:

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Test Lab MPLS FastReRouting

Transcript of MPLS FastReRouting

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MPLS T.E. FastReRouting

Fast Convergence In laboratorio si è voluto provare sia la funzionalità di MPLS T.E. FastReRouting che di IP FastRerouting allo

scopo di verificarne sia gli impatti che i tempi di convergenza in caso di failure.

Per quanto concerne l’MPLS T.E. F.R.R sono stati realizzati diversi tunnel MPLS in modo da realizzare una

magliatura MPLS tra i vari nodi PE.

Lo scopo è quello di creare e rendere disponibili percorsi LDP alternativi in modo da accelerare la

convergenza in caso di caduta di uno dei link di backbone.

Di seguito un estratto della configurazione utilizzata:

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interface Tunnel0 ip unnumbered Loopback0 tunnel mode mpls traffic-eng tunnel destination 10.150.100.6 tunnel mpls traffic-eng fast-reroute !

Si tiene a precisare che nel backbone MPLS della rete Leonardo non esistono link con bande geografiche

differenziate e pertanto l’uso classico del Traffic Engineering (unbalanced links) non abbia molto senso ed in

questo caso si è ricorsi al Traffic Engineering esclusivamente per la funzionalità di fast-reroute.

Per quanto concerne l’IP Fast Rerouting si è ricorso all’uso estensivo del protocollo BFD. Una delle

funzionalità introdotte con la release 12.2(33)SRC è quella del “BFD vrf aware” che consente l’utilizzo di tale

protocollo in ambiente PE-CE. Ulteriore caratteristica introdotta con la 12.2(33)SRC vi è la possibilità di

utilizzare BFD su datalink di tipo non broadcast quali ATM ed interfacce Seriali con imbustamento di tipo

FrameRelay. Il princio alla base del protocollo BFD è quello di monitorare con dei pacchetti estremamente

piccoli e leggeri (UDP) lo stato dei link punto-punto. In base a come il protocollo viene programmato, al

presentarsi di un evento di failure il sistema ne verificherà lo stato ripetendo il test diverse volte fino a

decretarne il definitivo down.

Il vantaggio del BFD rispetto alle altre funzionalità introdotte in passato è che lavora di concerto con i

diversi protocolli di routing ed MPLS. Al verificarsi di un evento di link failure, il sistema attiverà un processo

di notifica (triggered update) che riguarderà tutti i protocolli che siano stati configurati nella modalità di

BFD awareness. Questi messaggi di stato fanno si che nei router in cui si è verificato l’evento si proceda

direttamente al ricalcolo del routing senza dover attendere le normali procedure di convergenza basate su

timers.

Nei nodi PE attivando la funzionalità BFD sia per il protocollo OSPF che BGP, al verificarsi di una notifica di

link down si procederà automaticamente al ricalcolo protocollare. Questa funzionalità unita alla

caratteristica del multipath iBGP all’interno della vrf GEM dei nodi PE garantisce tempi di convergenza

rapidi e percorsi alternativi sempre disponibili.

address-family ipv4 vrf GEM no synchronization network 10.150.150.10 mask 255.255.255.255 redistribute connected neighbor 10.150.50.2 remote-as 2043 neighbor 10.150.50.2 fall-over bfd neighbor 10.150.50.2 activate maximum-paths ibgp 2 exit-address-family

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Durante il calcolo del best path verranno prese nell’address family BGP vrf GEM i migliori due path con

metrica paritetica (le rotte non potranno essere bilanciate se queste dovessero avere rispetto al router in

oggetto una metrica BGP differente). Nel caso di link failure l’address family BGP vrf GEM avrà già nella

propria tabella i potenziali percorsi alternativi. La figura sottostante mostra i potenziali percorsi di

instradamento dei router PT e PPA:

In caso di link failure il BFD, come mostrato nella figura sottostante, attiverà le notifiche ai protocolli BGP e

LDP.

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Di conseguenza viene immediatamente forzato il ricalcolo del protocollo BGP e l’associazione di queste

network con le label LDP.

Nella tabella sottostante viene riportata la mappatura della network di loopback del router PT all’interno

della tabella LDP del router PE3.

PE3#sh mpls forwarding-table vrf GEM 10.150.150.1 32 Local Outgoing Prefix Bytes Label Outgoing Next Hop Label Label or Tunnel Id Switched interface 17 No Label 10.150.150.1/32[V] \

0 AT1/0/0.100 point2point

In seguito ad un problema al link ATM tra PE3 e PPA, coaudivato dalla notifica BFD, il protocollo MPLS nel

router PE3 aggiorna la propria tabella LDP andando a selezionare il peering adiacente P3.

PE3#sh mpls forwarding-table vrf GEM 10.150.150.1 32 Local Outgoing Prefix Bytes Label Outgoing Next Hop Label Label or Tunnel Id Switched interface None 19 10.150.150.1/32[V] \ 0 Gi2/2 10.150.3.13

Come si può osservare dai log in condizioni normali viene generata la label locale 17 mentre in caso di

failure non figura alcuna label.

Analogamente viene verificato che il peering BFD tra i router PE3 e PT sia attivo e funzionante

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PE3#sh bfd neighbors vrf GEM ipv4 10.150.50.6 details IPv4 Sessions NeighAddr LD/RD RH/RS State Int 10.150.50.6 18/6 Up Up AT1/0/0.100 Session state is UP and using echo function with 999 ms interval. Session Host: Software OurAddr: 10.150.50.5 Local Diag: 0, Demand mode: 0, Poll bit: 0 MinTxInt: 1000000, MinRxInt: 1000000, Multiplier: 3 Received MinRxInt: 1000000, Received Multiplier: 3 Holddown (hits): 0(0), Hello (hits): 1000(3112) Rx Count: 3113, Rx Interval (ms) min/max/avg: 8/1000/878 last: 792 ms ago Tx Count: 3114, Tx Interval (ms) min/max/avg: 8/1000/877 last: 324 ms ago Elapsed time watermarks: 0 0 (last: 0) Elapsed time watermarks: 0 0 (last: 0) Registered protocols: CEF BGP Uptime: 00:45:30 Last packet: Version: 1 - Diagnostic: 0 State bit: Up - Demand bit: 0 Poll bit: 0 - Final bit: 0 Multiplier: 3 - Length: 24 My Discr.: 6 - Your Discr.: 18 Min tx interval: 1000000 - Min rx interval: 1000000 Min Echo interval: 999000

Dai log si può evincere che il peering BFD interessa i protocolli CEF e BGP.

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Discorso analogo per il router PE1:

PE1#sh bfd neighbors vrf GEM ipv4 10.150.50.2 details NeighAddr LD/RD RH/RS State Int 10.150.50.2 4/1 Up Up AT1/0/0.200 Session state is UP and using echo function with 999 ms interval. OurAddr: 10.150.50.1 Local Diag: 0, Demand mode: 0, Poll bit: 0 MinTxInt: 5000000, MinRxInt: 5000000, Multiplier: 3 Received MinRxInt: 1000000, Received Multiplier: 3 Holddown (hits): 0(0), Hello (hits): 5000(226770) Rx Count: 226761, Rx Interval (ms) min/max/avg: 12/5028/4379 last: 1240 ms ago Tx Count: 226772, Tx Interval (ms) min/max/avg: 8/5004/4383 last: 2480 ms ago Elapsed time watermarks: 0 0 (last: 0) Registered protocols: CEF BGP Uptime: 1w4d Last packet: Version: 1 - Diagnostic: 0 State bit: Up - Demand bit: 0 Poll bit: 0 - Final bit: 0 Multiplier: 3 - Length: 24 My Discr.: 1 - Your Discr.: 4 Min tx interval: 1000000 - Min rx interval: 1000000 Min Echo interval: 999000 PE1#

La scelta dei timers BFD è stato uno dei punti di maggiore attenzione dell’intera architettura. Premesso che

il BFD nella macchine di backbone viene gestito a livello hardware sollevando la CPU centrale dalla gestione

dei vari peer, è altrettato doveroso precisare che timers eccessivamente aggressivi possono condurre alla

notifica di falsi responsi positivi. Nei nodi PE sono stati testati con successo timers BFD nell’ordine dei 150-

300 ms. Per i nodi CE il discorso è leggermente diverso in quanto il problema principale è costituito dalla

velocità dei circuiti geografici. In caso di congestione del link potrebbe verificarsi l’evento di una perdita di

pacchetti di controllo BFD con conseguente notifica al protocollo di routing. Come best practice sono stati

introdotti dei timers BFD nell’ordine del secondo (999 ms per la precisione).

Nel caso di problemi ai link dei nodi di backbone, la notifica è pressochè immediata ed impercettibile dal

punto di vista applicativo (ping). Ottimi i risultati nei router CE dove i tempi di notifica e riconvergenza

protocollare sono nel range tra il secondo ed il secondo e ½.

Prendendo come riferimento il nodo PE3 prima di iniziare il test si verifica che la raggiungibilità IP

dell’interfaccia di loopback del router PT sia valida e funzionante.

PE3#ping vrf GEM 10.150.150.1 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.150.150.1, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 12/15/16 ms PE3#sh ip cef vrf GEM 10.150.150.1 10.150.150.1/32 nexthop 10.150.50.6 ATM1/0/0.100

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Prima di procedere con l’evento di link failure si analizza lo stato del protocollo BGP nel nodo PE3:

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PE3#sh ip bgp vpnv4 vrf GEM neighbors 10.150.50.6 BGP neighbor is 10.150.50.6, vrf GEM, remote AS 2043, external link Fall over configured for session BFD is configured. Using BFD to detect fast fallover BGP version 4, remote router ID 10.150.150.1 BGP state = Established, up for 00:04:53 Last read 00:00:00, last write 00:00:02, hold time is 18, keepalive interval is 6 seconds Configured hold time is 18, keepalive interval is 6 seconds Minimum holdtime from neighbor is 0 seconds Neighbor sessions: 1 active, is multisession capable (disabled) Neighbor capabilities: Route refresh: advertised and received(new) Four-octets ASN Capability: advertised and received Address family IPv4 Unicast: advertised and received Graceful Restart Capability: advertised and received Remote Restart timer is 120 seconds Address families advertised by peer: none Multisession Capability: and received Message statistics, state Established: InQ depth is 0 OutQ depth is 0 Sent Rcvd Opens: 1 1 Notifications: 0 0 Updates: 8 7 Keepalives: 51 49 Route Refresh: 0 0 Total: 60 57 Default minimum time between advertisement runs is 0 seconds For address family: VPNv4 Unicast Translates address family IPv4 Unicast for VRF GEM Session: 10.150.50.6 BGP table version 197, neighbor version 197/0 Output queue size : 0 Index 5, Advertise bit 0 5 update-group member Slow-peer detection is disabled Slow-peer split-update-group dynamic is disabled Sent Rcvd Prefix activity: ---- ---- Prefixes Current: 9 1 (Consumes 56 bytes) Prefixes Total: 142 1 Implicit Withdraw: 122 0 Explicit Withdraw: 9 0 Used as bestpath: n/a 1 Used as multipath: n/a 0 Outbound Inbound Local Policy Denied Prefixes: -------- ------- AS_PATH loop: n/a 8 Bestpath from this peer: 2 n/a Invalid Path: 9 n/a Total: 11 8 Number of NLRIs in the update sent: max 2, min 0 Last detected as dynamic slow peer: never Dynamic slow peer recovered: never Address tracking is enabled, the RIB does have a route to 10.150.50.6 Connections established 5; dropped 4 Last reset 00:05:03, due to Interface flap of session 1 Transport(tcp) path-mtu-discovery is enabled Graceful-Restart is enabled, restart-time 120 seconds, stalepath-time 360 seconds Connection state is ESTAB, I/O status: 1, unread input bytes: 0 Connection is ECN Disabled Mininum incoming TTL 0, Outgoing TTL 1 Local host: 10.150.50.5, Local port: 16050 Foreign host: 10.150.50.6, Foreign port: 179 Connection tableid (VRF): 1 Enqueued packets for retransmit: 0, input: 0 mis-ordered: 0 (0 bytes) Event Timers (current time is 0x7307EED8): Timer Starts Wakeups Next Retrans 54 0 0x0 TimeWait 0 0 0x0 AckHold 52 48 0x7307EF54 SendWnd 0 0 0x0 KeepAlive 0 0 0x0 GiveUp 0 0 0x0

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Si riporta un estratto della configurazione del circuito logico ATM che rilega il nodo PE3 con il router PT

interface ATM1/0/0.100 point-to-point ip vrf forwarding GEM ip address 10.150.50.5 255.255.255.252 logging event subif-link-status no atm enable-ilmi-trap bfd interval 999 min_rx 999 multiplier 3 pvc 2/100 vbr-nrt 56 48 oam retry 3 3 1 encapsulation aal5snap ! end

Come descritto in precedenza i timers BFD per le interfacce che rilegano i PE con i CE vengono impostati a

999ms.

Si procede con lo spengimento del circuito logico che rilega il nodo PE3 con il router PT:

PE3#conf t Enter configuration commands, one per line. End with CNTL/Z. PE3(config)#inter atm 1/0/0.100 PE3(config-subif)#shut PE3(config-subif)#

Dai log viene immediatamente notificato il link down e la conseguente segnalazione BGP:

*May 10 16:48:29.639: %LINK-3-UPDOWN: Interface ATM1/0/0.100, changed state to administratively down *May 10 16:48:29.639: %LINEPROTO-5-UPDOWN: Line protocol on Interface ATM1/0/0.100, changed state to down *May 10 16:48:29.639: %ATM-6-PVC_STATE_CHANGE: ATM(ATM1/0/0.100): PVC(VCD=4, VPI=2, VCI=100) state changed to SHUTTING_DOWN. *May 10 16:48:29.643: %BGP-5-ADJCHANGE: neighbor 10.150.50.6 vpn vrf GEM Down Interface flap *May 10 16:48:29.643: %BGP_SESSION-5-ADJCHANGE: neighbor 10.150.50.6 IPv4 Unicast vpn vrf GEM topology base removed from session Interface flap *May 10 16:48:29.651: %ATM-6-PVC_STATE_CHANGE: ATM(ATM1/0/0.100): PVC(VCD=4, VPI=2, VCI=100) state changed to NOT_IN_SERVICE.

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Nel frattempo dal nodo PPA viene fatto partire un test icmp verso la loopback del router PT. Rispetto al

router PPA, la simulazione di failure dell’interfaccia ATM 1/0/0.100 risulta essere una failure indiretta

(peggiore condizione):

PPA#ping 10.150.150.1 repeat 10000 Type escape sequence to abort. Sending 10000, 100-byte ICMP Echos to 10.150.150.1, timeout is 2 seconds: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!.!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Success rate is 99 percent (750/751), round-trip min/avg/max = 12/16/56 ms PPA#

Durante la fase di failure si è verificata la perdita di un solo pacchetto ICMP.

Identico test è stato ripetuto partendo dal medesimo scenario di link failure:

PE3(config-subif)#no shut PE3(config-subif)# *May 10 16:48:37.779: %ATM-6-PVC_STATE_CHANGE: ATM(ATM1/0/0.100): PVC(VCD=4, VPI=2, VCI=100) state changed to UP. *May 10 16:48:37.783: %LINK-3-UPDOWN: Interface ATM1/0/0.100, changed state to up *May 10 16:48:37.783: %LINEPROTO-5-UPDOWN: Line protocol on Interface ATM1/0/0.100, changed state to up *May 10 16:48:39.959: %BGP-5-ADJCHANGE: neighbor 10.150.50.6 vpn vrf GEM Up PE3(config-subif)#

In questo caso la notifica di cambio di stato e la conseguente procedura di ricalcolo del protocollo BGP non

ha comportato alcuna perdita di dati.

NOTA

Per consentire l’uso del BFD nei router CE è necessario effettuare un upgrade di release alla 15.0(1)M

mentre nei router PE è stata testata con successo sia la 12.2(33)SRE che la 15.1(2)S

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Dai test condotti è risultato che l’implementazione dell’MPLS T.E. F.R.R. non abbia portato a differenze

degne di nota rispetto all’implementazione dell’IP F.R.R. e di conseguenza vista anche la maggiore

semplicità di utilizzo si raccomanda l’uso di quest’ultimo.

Schema e Apparati coinvolti

A tale scopo sono stati realizzati circuiti SRP tra i tre nodi P costituiti da apparati Cisco GSR 12000 a cui sono

stati collegati tre nodi distinti PE della fascia Cisco C7600.

Per i nodi P è stato utilizzato un doppio anello POS SRP da 2,5Gbps ciascuno. Per i collegamenti dei nodi PE

verso i P si è scelto di utilizzare link in fibra con datalink GigaEthernet.

Come da schema, i collegamenti PE verso il backbone MPLS utilizzano due router P distinti.

A dimostrazione della validità della soluzione i nodi CE (PPA e PT) debbono attraversare nodi PE distinti.

Inoltre come da rappresentazione sottostante

P3 P2 P1

2046

10.150.1x/24

10.150.2.x/24

10.150.3.12/30

3

.3

.2

.2

.1

.1

13G1/2/0

G1/2/2

10.150.3.8/30

9 1

MPLS

PE3

14

10G2/2

10.150.3.x/30

2G2/2

PE1 PE2

G2/2

G1/2/0

OSPF

Backbone

Area

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si è voluto replicare una nuvola geografica con interworking ATM/FRAME RELAY.

Per carenza di schede seriali di tipo E1 si è potuto simulare il circuito Frame Relay esclusivamente nel nodo

PT. Per il nodo PPA si è optato per una scheda di tipo ATM E3. Pur tuttavia la indisponibilità di una ulteriore

scheda E1 non ha comportato alcuna apprezzabile limitazione per la soluzione testata.

Allo scopo di semplificare la comprensione dei rilegamenti logici è stata prevista una mappatura dei pvc

ATM su base parititetica (stesso valore di pvc PE-PPA).

Nodo PVC DLCI Interfaccia Switch ATM

P2P

PE1 2/200 ATM 1/0/0 PT PE3 2/100 ATM 1/0/1 PT PE3 2/101 ATM 1/0/1 PPA PE2 2/102 ATM 1/0/2 PPA PT 43 E1 0/1/3 PE1 PT 44 E1 0/1/3 PE3

Per i DLCI si è utilizzata una mappatura differenziata che riflette la seguente logica di Interworking

ATM/FrameRelay :

Nodo PVC Nodo DLCI

PE1 2/200 PT 43 PE3 2/100 PT 44

La mappatura di interworking frame-relay / ATM è stata realizzata simulando nello switch ATM un clock

rate pari a 56Kbps. La connessione lato Switch è stata impostata utilizzando la funzionalità di DCE verso

l’interfaccia seriale e di clock source verso ATM.

PE1

PE3

PE2

PPAPT

DLCI 43 DLCI 44

PVC 2/200

PVC 2/100PVC 2/101

PVC 2/101

PVC 2/102

PVC 2/102

ATM/FrameRelay

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Di seguito un estratto di configurazione di interworking FrameRelay/ATM realizzato nel nodo di switch

ATM:

interface Serial0/1/3:1 no ip address encapsulation frame-relay IETF no arp frame-relay frame-relay lmi-type ansi frame-relay pvc 43 service translation interface ATM1/0/0 2 200 atm oam interface ATM1/0/0 2 200 ais rdi frame-relay pvc 44 service translation interface ATM1/0/1 2 100 atm oam interface ATM1/0/1 2 100 ais rdi frame-relay intf-type dce

IP Address Per lo schema di indirizzamento IP si è utilizzata la subnet 10.150.0.0/16 che risulta essere dedicata agli

ambienti di test plant Enel.

Indirizzamento IP nodi P

Nodo Intf network IP Nodo Intf IP Nodo Intf IP P1 SRP 2/0 10.150.1.0/24 .1 P2 SRP 2/0 .2 P3 SRP 2/0 .3 P1 SRP 2/1 10.150.2.0/24 .1 P2 SRP 2/1 .2 P3 SRP 2/1 .3

Indirizzamento IP nodi P-PE

Nodo Intf network IP Nodo Intf IP P1 Ge1/2/0 10.150.3.0/30 .1 PE2 Ge 2/2 .2 P3 Ge1/2/0 10.150.3.8/30 .9 PE1 Ge 2/2 .10 P3 Ge1/2/2 10.150.3.12/30 .13 PE3 Ge 2/2 .14

Indirizzamento IP nodi PE-CE

Nodo Intf network IP Nodo Intf IP PE1 ATM 1/0/0.200 10.150.50.0/30 .1 PT S1/0:1.43 .2 PE3 ATM 1/0/0.100 10.150.50.4/30 .5 PT S1/0:1.44 .6 PE3 ATM 1/0/0.101 10.150.50.8/30 .9 PPA ATM1/0.101 .10 PE2 ATM 1/0/0.102 10.150.50.12/30 .13 PPA ATM1/0.102 .14

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Indirizzamento IP loopback

Nodo Loopback

P1 10.150.100.1/32 P2 10.150.100.2/32 P3 10.150.100.3/32 PE1 10.150.100.5/32 PE2 10.150.100.7/32 PE3 10.150.100.6/32 PT 10.150.150.1/32 PPA 10.150.150.1/32

Routing Per il processo di routing OSPF si è scelta una configurazione analoga a quella presente nei nodi MPLS della

rete Leonardo. Laddove è presente un doppio route-processor sono stati introdotti i comandi di

NonStopForwarding e di StatefulSwitchOver per accelerare la convergenza in caso di caduta di una delle

schede di route-engine.

Nel backbone le tempistiche di convergenza OSPF sono state ottimizzate per garantire una tempestività

tale da consentire la riconvergenza protocollare dell’OSPF senza causare disservizi ai restanti protocolli di

routing (BGP). Di seguito un estratto di configurazione del processo di routing OSPF

router ospf 1 router-id 10.150.100.2 ispf log-adjacency-changes nsf mpls ldp sync timers throttle spf 50 50 5000 timers throttle lsa all 0 20 5000 timers lsa arrival 15 timers pacing flood 15 network 10.150.1.0 0.0.0.255 area 0 network 10.150.2.0 0.0.0.255 area 0 network 10.150.100.2 0.0.0.0 area 0 bfd all-interfaces

Si può notare come il processo di routing OSPF tenga conto di ulteriori aspetti protocollari:

la sincronizzazione del protocollo LDP con l’OSPF consente di evitare fenomeni di packet loss in caso i due

protocolli non siano in fase:

In caso di failure di uno o più link potrebbe accadere che l’adiacenza OSPF venga utilizzata al posto di quella

LDP in quanto quest’ultima potrebbe non avere concluso la fase di peer exchange.

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Analogo comportamento potrebbe presentarsi nel caso in cui una sessione di peering LDP venga interrotta

bruscamente (crash della linecard oppure shutdown forzato) ed in tal caso il router continuerà ad inoltrare

il traffico lungo quel circuito con il peer LDP down.

In laboratorio sono stati condotti diversi test di caduta di circuito P-PE e crash di linecard dei nodi P. Dato il

numero esiguo di rotte l’unico effetto riscontrato è stato quello di un disallineamento dei link di forwarding

LDP rispetto alle rotte IGP. Ripetendo il test dopo l’introduzione del comando “mpls ldp sync” il

disallineamento non si è più presentato.

P_CORE_03#sh ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 10.150.100.6 0 FULL/ - 00:00:37 10.150.3.14 GigabitEthernet1/2/2 10.150.100.5 0 FULL/ - 00:00:36 10.150.3.10 GigabitEthernet1/2/0 10.150.100.1 1 FULL/BDR 00:00:34 10.150.2.1 SRP2/1 10.150.100.2 1 FULL/DROTHER 00:00:30 10.150.2.2 SRP2/1 10.150.100.1 1 FULL/BDR 00:00:32 10.150.1.1 SRP2/0 10.150.100.2 1 FULL/DROTHER 00:00:30 10.150.1.2 SRP2/0 P_CORE_03#

Analizzando le adiacenze OSPF dei nodi P e PE si denota che i link PE-P in GigaEthernet vengono configurati

come dei point-to-point OSPF mentre i link P-P di tipo SRP vengono lasciati in modalità broadcast.

PE3#sh ip ospf neighbor detail Neighbor 10.150.100.3, interface address 10.150.3.13 In the area 0 via interface GigabitEthernet2/2, BFD enabled Neighbor priority is 0, State is FULL, 6 state changes DR is 0.0.0.0 BDR is 0.0.0.0 Options is 0x12 in Hello (E-bit, L-bit) Options is 0x52 in DBD (E-bit, L-bit, O-bit) LLS Options is 0x1 (LR) Dead timer due in 00:00:33 Neighbor is up for 3w0d Index 1/1, retransmission queue length 0, number of retransmission 1 First 0x0(0)/0x0(0) Next 0x0(0)/0x0(0) Last retransmission scan length is 1, maximum is 1 Last retransmission scan time is 0 msec, maximum is 0 msec

Come mostrato nelle tabelle di log un ulteriore aspetto di ottimizzazione è dato dall’uso del protocollo BFD

nel processo di routing OSPF. L’uso di questo protocollo è alla base del processo di IP Fast Re Routing che

verrà trattato più avanti in una apposita sessione.

BFD viene introdotto in tutti i link GigaEthernet del backbone mentre le interfacce SRP avendo nativamente

una tecnologia di protezione sia di circuito che di logica (doppia scheda – doppia linecard – doppio circuito)

non vengono interessate da questa funzionalità:

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P_CORE_03#sh bfd neighbors Cleanup timer hits: 0 OurAddr NeighAddr LD/RD RH Holdown(mult) State Int 10.150.3.13 10.150.3.14 17/0 0 0 (0 ) Up Gi1/2/2 10.150.3.9 10.150.3.10 18/0 0 0 (0 ) Up Gi1/2/0 Total Adjs Found: 256 P_CORE_03#execute-on slot 1 show bfd nei ========= Line Card (Slot 1) ========= Cleanup timer hits: 0 OurAddr NeighAddr LD/RD RH Holdown(mult) State Int 10.150.3.13 10.150.3.14 17/3 1 118 (3 ) Up Gi1/2/2 10.150.3.9 10.150.3.10 18/1 1 130 (3 ) Up Gi1/2/0 Total Adjs Found: 256 P_CORE_03#execute-on slot 1 show bfd nei deta ========= Line Card (Slot 1) ========= Cleanup timer hits: 0 OurAddr NeighAddr LD/RD RH Holdown(mult) State Int 10.150.3.13 10.150.3.14 17/3 1 118 (3 ) Up Gi1/2/2 Local Diag: 0, Demand mode: 0, Poll bit: 0 MinTxInt: 50000, MinRxInt: 50000, Multiplier: 3 Received MinRxInt: 50000, Received Multiplier: 3 Holdown (hits): 150(0), Hello (hits): 50(21705098) Rx Count: 39439051, Rx Interval (ms) min/max/avg: 40/56/46 last: 32 ms ago Tx Count: 21705102, Tx Interval (ms) min/max/avg: 52/116/85 last: 0 ms ago Last packet: Version: 0 - Diagnostic: 0 I Hear You bit: 1 - Demand bit: 0 Poll bit: 0 - Final bit: 0 Multiplier: 3 - Length: 24 My Discr.: 3 - Your Discr.: 17 Min tx interval: 50000 - Min rx interval: 50000 Min Echo interval: 50000 Uptime: 3w0d OurAddr NeighAddr LD/RD RH Holdown(mult) State Int 10.150.3.9 10.150.3.10 18/1 1 134 (3 ) Up Gi1/2/0 Local Diag: 0, Demand mode: 0, Poll bit: 0 MinTxInt: 50000, MinRxInt: 50000, Multiplier: 3 Received MinRxInt: 50000, Received Multiplier: 3 Holdown (hits): 150(0), Hello (hits): 50(11286079) Rx Count: 20515112, Rx Interval (ms) min/max/avg: 36/56/46 last: 8 ms ago Tx Count: 11286089, Tx Interval (ms) min/max/avg: 52/112/84 last: 28 ms ago Last packet: Version: 0 - Diagnostic: 0 I Hear You bit: 1 - Demand bit: 0 Poll bit: 0 - Final bit: 0 Multiplier: 3 - Length: 24 My Discr.: 1 - Your Discr.: 18 Min tx interval: 50000 - Min rx interval: 50000 Min Echo interval: 50000 Uptime: 1w4d SSO Cleanup Timer called: 0 SSO Cleanup Action Taken: 0 Pseudo pre-emptive process count: 185428500 min/max/avg: 8/28/11 last: 8 ms ago IPC Tx Failure Count: 0 IPC Rx Failure Count: 0 Total Adjs Found: 256 P_CORE_03#

Page 17: MPLS  FastReRouting

Si tiene a precisare che i nodi P non partecipano minimamente al processo di routing BGP. Nella rete

Leonardo i nodi P partecipano al processo BGP in qualità di route-reflectors mentre nel laboratorio il basso

numero di nodi PE interessati non necessita di dover ricorrere all’uso di uno o più route-reflectors.

Di seguito viene riportato un estratto di configurazione del protocollo BGP:

Router bgp 64600 no synchronization bgp router-id 10.150.100.5 bgp log-neighbor-changes bgp graceful-restart restart-time 120 bgp graceful-restart stalepath-time 360 bgp graceful-restart timers bgp 6 18 neighbor 10.150.100.6 remote-as 64600 neighbor 10.150.100.6 description PE3 neighbor 10.150.100.6 update-source Loopback0 neighbor 10.150.100.6 fall-over bfd neighbor 10.150.100.7 remote-as 64600 neighbor 10.150.100.7 description PE2 neighbor 10.150.100.7 update-source Loopback0 neighbor 10.150.100.7 fall-over bfd no auto-summary !

Anche in questo caso si può notare l’uso delle funzionalità di graceful-restart e di BFD per i peering iBGP dei

nodi PE.

Page 18: MPLS  FastReRouting

Configurazioni Configurazione P1 P_CORE_01

Building configuration...

Current configuration : 3244 bytes

!

upgrade fpd auto

version 12.0

no service pad

service timestamps debug datetime msec

service timestamps log datetime msec localtime

no service password-encryption

!

hostname P_CORE_01

!

boot-start-marker

boot system flash disk0:c12kprp-k4p-mz.120-31.S3.bin

boot-end-marker

!

!

redundancy

mode rpr

logging count

logging buffered 400000 debugging

enable secret 5 $1$Gi5J$2.l/5CajZHeo4yXFApdOy1

!

monitor event-trace rlc all enable

clock timezone GMT 1

Page 19: MPLS  FastReRouting

clock summer-time GMT recurring

!

!

!

ip subnet-zero

ip cef table hardware resource-failure action punt

ip tcp path-mtu-discovery

no ip domain-lookup

ip ssh time-out 120

ip ssh authentication-retries 3

mpls label protocol ldp

mpls ldp graceful-restart timers neighbor-liveness 60

mpls ldp graceful-restart timers max-recovery 60

mpls ldp graceful-restart

mpls ldp session protection duration 30

tag-switching tdp router-id Loopback0 force

!

controller T1 0/0

!

controller E1 0/1

!

controller T1 3/0

!

controller E1 3/1

!

!

interface Loopback0

description loopback per ospf

Page 20: MPLS  FastReRouting

ip address 10.150.100.1 255.255.255.255

no ip directed-broadcast

!

interface Loopback1

description loopback per ldp

ip address 10.150.100.11 255.255.255.255

no ip directed-broadcast

!

interface GigabitEthernet1/2/0

description vs PE2 G2/2

mtu 2312

ip address 10.150.3.1 255.255.255.252

no ip directed-broadcast

ip ospf network point-to-point

negotiation auto

tag-switching ip

bfd interval 50 min_rx 50 multiplier 3

!

interface GigabitEthernet1/2/1

dampening 30 1 362 255

description vs PE_Accesso_01 5/1

mtu 2312

ip address 10.150.3.5 255.255.255.252

no ip directed-broadcast

ip ospf network point-to-point

shutdown

negotiation auto

tag-switching ip

Page 21: MPLS  FastReRouting

!

interface GigabitEthernet1/2/2

dampening 30 1 362 255

description vs PE_CED_01 2/1

mtu 2312

ip address 10.150.3.37 255.255.255.252

no ip directed-broadcast

ip ospf network point-to-point

shutdown

negotiation auto

tag-switching ip

!

interface GigabitEthernet1/3/0

dampening 30 1 362 255

description vs PE_CED_01 5/1

mtu 2312

ip address 10.150.3.33 255.255.255.252

no ip directed-broadcast

ip ospf network point-to-point

negotiation auto

tag-switching ip

!

interface SRP2/0

description vs P_Core01-P_Core03

mtu 2312

ip address 10.150.1.1 255.255.255.0

no ip directed-broadcast

load-interval 30

Page 22: MPLS  FastReRouting

tag-switching ip

srp clock-source line b

!

interface SRP2/1

description vs P_Core01-P_Core03

mtu 2312

ip address 10.150.2.1 255.255.255.0

no ip directed-broadcast

load-interval 30

tag-switching ip

srp clock-source line b

!

!

router ospf 1

router-id 10.150.100.1

ispf

log-adjacency-changes

auto-cost reference-bandwidth 10000

nsf

mpls ldp sync

network 10.150.1.0 0.0.0.255 area 0

network 10.150.2.0 0.0.0.255 area 0

network 10.150.3.0 0.0.0.3 area 0

network 10.150.100.1 0.0.0.0 area 0

bfd all-interfaces

!

ip classless

!

Page 23: MPLS  FastReRouting

!

!

!

control-plane

!

alias exec ib show ip interface brief

!

line con 0

line aux 0

line vty 0 4

password cisco

login

!

exception warmstart 60 5

no cns aaa enable

end

Page 24: MPLS  FastReRouting

Configurazione P2 P_CORE_02

Building configuration...

Current configuration : 3528 bytes

!

upgrade fpd auto

version 12.0

no service pad

service timestamps debug datetime msec

service timestamps log datetime msec localtime

no service password-encryption

!

hostname P_CORE_02

!

boot-start-marker

boot system flash disk0:c12kprp-k4p-mz.120-31.S3.bin

boot-end-marker

!

!

redundancy

mode rpr

logging count

logging buffered 400000 debugging

enable secret 5 $1$kex3$eIAxSnPXA8LD7VPP8di/50

enable password cisco

!

monitor event-trace rlc all enable

Page 25: MPLS  FastReRouting

clock timezone GMT 1

clock summer-time GMT recurring

!

!

!

ip subnet-zero

ip cef table hardware resource-failure action punt

ip tcp path-mtu-discovery

no ip domain-lookup

ip ssh time-out 120

ip ssh authentication-retries 3

mpls label protocol ldp

mpls ldp graceful-restart timers neighbor-liveness 60

mpls ldp graceful-restart timers max-recovery 60

mpls ldp graceful-restart

mpls ldp session protection duration 30

tag-switching tdp router-id Loopback0 force

!

controller T1 0/0

!

controller E1 0/1

!

controller T1 3/0

!

controller E1 3/1

!

!

interface Loopback0

Page 26: MPLS  FastReRouting

description Loopback per ospf

ip address 10.150.100.2 255.255.255.255

no ip directed-broadcast

!

interface GigabitEthernet1/2/0

dampening 30 1 362 255

description vs PE_CED_02 2/1

mtu 2312

no ip address

no ip directed-broadcast

ip ospf network point-to-point

negotiation auto

tag-switching ip

bfd interval 300 min_rx 300 multiplier 3

!

interface GigabitEthernet1/2/1

dampening 30 1 362 255

description vs PE_CED_02 5/1

mtu 2312

no ip address

no ip directed-broadcast

ip ospf network point-to-point

negotiation auto

tag-switching ip

bfd interval 300 min_rx 300 multiplier 3

!

interface GigabitEthernet1/2/2

no ip address

Page 27: MPLS  FastReRouting

no ip directed-broadcast

shutdown

negotiation auto

!

interface GigabitEthernet1/3/0

mtu 2312

no ip address

no ip directed-broadcast

ip ospf network point-to-point

negotiation auto

mpls label protocol ldp

tag-switching ip

!

interface SRP2/0

description vs P_Core_01-P_Core_03

mtu 2312

ip address 10.150.1.2 255.255.255.0

no ip directed-broadcast

load-interval 30

tag-switching ip

srp clock-source line b

!

interface SRP2/1

description vs P_Core_01-P_Core_03

mtu 2312

ip address 10.150.2.2 255.255.255.0

no ip directed-broadcast

load-interval 30

Page 28: MPLS  FastReRouting

tag-switching ip

srp clock-source line b

!

interface Ethernet0

no ip address

no ip directed-broadcast

shutdown

!

interface Ethernet1

no ip address

no ip directed-broadcast

shutdown

!

interface Ethernet2

no ip address

no ip directed-broadcast

shutdown

!

router ospf 1

router-id 10.150.100.2

ispf

log-adjacency-changes

nsf

mpls ldp sync

timers throttle spf 50 50 5000

timers throttle lsa all 0 20 5000

timers lsa arrival 15

timers pacing flood 15

Page 29: MPLS  FastReRouting

network 10.150.1.0 0.0.0.255 area 0

network 10.150.2.0 0.0.0.255 area 0

network 10.150.100.2 0.0.0.0 area 0

bfd all-interfaces

!

ip classless

!

ip bgp-community new-format

!

!

!

control-plane

!

line con 0

line aux 0

line vty 0 4

password cisco

login

line vty 5 15

password cisco

login

!

exception warmstart 60 5

no cns aaa enable

end

Page 30: MPLS  FastReRouting

Configurazione P3 P_CORE_03

Current configuration : 4028 bytes

!

upgrade fpd auto

version 12.0

no service pad

service timestamps debug datetime msec

service timestamps log datetime msec localtime

no service password-encryption

!

hostname P_CORE_03

!

boot-start-marker

boot system flash disk0:c12kprp-k4p-mz.120-31.S3.bin

boot-end-marker

!

!

redundancy

mode rpr

logging count

logging buffered 400000 debugging

enable secret 5 $1$.L83$qG67qizMnsHW6LlVub5P9/

!

monitor event-trace rlc all enable

clock timezone GMT 1

clock summer-time GMT recurring

Page 31: MPLS  FastReRouting

!

!

!

ip subnet-zero

ip cef table hardware resource-failure action punt

ip tcp path-mtu-discovery

no ip domain-lookup

ip ssh time-out 120

ip ssh authentication-retries 3

mpls label protocol ldp

mpls ldp graceful-restart timers neighbor-liveness 60

mpls ldp graceful-restart timers max-recovery 60

mpls ldp graceful-restart

mpls ldp session protection duration 30

tag-switching tdp router-id Loopback0 force

!

controller T1 0/0

!

controller E1 0/1

!

controller T1 3/0

!

controller E1 3/1

!

!

interface Loopback0

description loopback per ospf

ip address 10.150.100.3 255.255.255.255

Page 32: MPLS  FastReRouting

no ip directed-broadcast

!

interface Loopback1

description loopback per ldp

ip address 10.150.100.31 255.255.255.255

no ip directed-broadcast

!

interface GigabitEthernet1/2/0

dampening 30 1 362 255

description vs PE_Accesso_02 2/1

mtu 2312

ip address 10.150.3.9 255.255.255.252

no ip directed-broadcast

ip ospf network point-to-point

negotiation auto

tag-switching ip

bfd interval 50 min_rx 50 multiplier 3

!

interface GigabitEthernet1/2/1

dampening 30 1 362 255

description vs PE_Accesso_02 5/1

mtu 2312

no ip address

no ip directed-broadcast

ip ospf network point-to-point

shutdown

negotiation auto

tag-switching ip

Page 33: MPLS  FastReRouting

!

interface GigabitEthernet1/2/2

dampening 30 1 362 255

description vs PE3 G2/2

mtu 2312

ip address 10.150.3.13 255.255.255.252

no ip directed-broadcast

ip ospf network point-to-point

negotiation auto

tag-switching ip

bfd interval 50 min_rx 50 multiplier 3

!

interface GigabitEthernet1/3/0

no ip address

no ip directed-broadcast

shutdown

negotiation auto

!

interface SRP2/0

description vs P_Core_01-P_Core_02

mtu 2312

ip address 10.150.1.3 255.255.255.0

no ip directed-broadcast

load-interval 30

tag-switching ip

srp clock-source line b

!

interface SRP2/1

Page 34: MPLS  FastReRouting

description vs P_Core_01-P_Core_02

mtu 2312

ip address 10.150.2.3 255.255.255.0

no ip directed-broadcast

load-interval 30

tag-switching ip

srp clock-source line b

!

interface Ethernet0

no ip address

no ip directed-broadcast

shutdown

!

interface Ethernet1

no ip address

no ip directed-broadcast

shutdown

!

interface Ethernet2

no ip address

no ip directed-broadcast

shutdown

!

router ospf 1

router-id 10.150.100.3

ispf

log-adjacency-changes

nsf

Page 35: MPLS  FastReRouting

mpls ldp sync

timers throttle spf 50 50 5000

timers throttle lsa all 0 20 5000

timers lsa arrival 15

timers pacing flood 15

network 10.150.1.3 0.0.0.0 area 0

network 10.150.2.3 0.0.0.0 area 0

network 10.150.3.9 0.0.0.0 area 0

network 10.150.3.13 0.0.0.0 area 0

network 10.150.100.3 0.0.0.0 area 0

network 10.150.100.31 0.0.0.0 area 0

bfd all-interfaces

!

router bgp 64581

no synchronization

bgp cluster-id 1

bgp log-neighbor-changes

bgp graceful-restart restart-time 120

bgp graceful-restart stalepath-time 360

bgp graceful-restart

bgp nexthop trigger delay 0

timers bgp 6 18

neighbor 10.150.100.2 remote-as 64581

neighbor 10.150.100.2 description to P_Core_02

neighbor 10.150.100.2 update-source Loopback0

neighbor 10.150.100.2 fall-over

neighbor 10.150.100.2 advertisement-interval 1

neighbor 10.150.100.4 remote-as 64581

Page 36: MPLS  FastReRouting

neighbor 10.150.100.4 description to PE_Accesso_01

neighbor 10.150.100.4 update-source Loopback0

neighbor 10.150.100.4 fall-over

neighbor 10.150.100.4 route-reflector-client

neighbor 10.150.100.4 advertisement-interval 1

no auto-summary

!

ip classless

!

!

!

!

control-plane

!

alias exec ib show ip interface brief

!

line con 0

line aux 0

line vty 0 4

password cisco

login

!

exception warmstart 60 5

no cns aaa enable

end

Page 37: MPLS  FastReRouting

Configurazione PE1 Building configuration...

Current configuration : 8643 bytes

!

! Last configuration change at 15:45:22 GMT Fri Apr 29 2011

!

version 12.2

service timestamps debug uptime

service timestamps log uptime

service internal

service counters max age 10

!

hostname PE1

!

boot-start-marker

boot system flash disk0:c7600s72033-advipservicesk9-mz.122-33.SRE3.bin

boot-end-marker

!

enable secret 5 $1$h/hP$hiqhdiob3Fq18TbVzh3Ym1

!

no aaa new-model

!

!

!

clock timezone GMT 1

clock summer-time GMT recurring

Page 38: MPLS  FastReRouting

ip source-route

ip vrf GEM

rd 10:11

route-target export 10:10

route-target import 10:10

!

!

!

no ip domain lookup

!

!

!

!

vtp domain testplant

vtp mode transparent

no mpls ip propagate-ttl

mpls label protocol ldp

mls ip cef load-sharing full

mls flow ip interface-full

no mls flow ipv6

mls qos protocol BFD-CTRL pass-through

mls qos protocol BFD-ECHO pass-through

mls qos

no mls acl tcam share-global

mls cef error action freeze

multilink bundle-name authenticated

!

!

Page 39: MPLS  FastReRouting

!

!

!

spanning-tree mode pvst

no spanning-tree optimize bpdu transmission

spanning-tree extend system-id

diagnostic bootup level minimal

no diagnostic cns publish

no diagnostic cns subscribe

!

redundancy

main-cpu

auto-sync running-config

mode sso

bfd slow-timers 5000

!

vlan internal allocation policy ascending

vlan access-log ratelimit 2000

!

ip tcp path-mtu-discovery

interface Loopback0

description Loopback per ospf

ip address 10.150.100.5 255.255.255.255

!

interface Loopback100

ip vrf forwarding GEM

ip address 10.150.150.10 255.255.255.255

!

Page 40: MPLS  FastReRouting

interface Tunnel0

ip unnumbered Loopback0

tunnel mode mpls traffic-eng

tunnel destination 10.150.100.6

tunnel mpls traffic-eng fast-reroute

!

interface ATM1/0/0

mtu 1500

no ip address

logging event link-status

atm uni-version 3.1

no atm auto-configuration

no atm address-registration

no atm ilmi-enable

no atm enable-ilmi-trap

!

interface ATM1/0/0.200 point-to-point

ip vrf forwarding GEM

ip address 10.150.50.1 255.255.255.252

no ip redirects

no ip unreachables

logging event subif-link-status

no atm enable-ilmi-trap

bfd interval 999 min_rx 999 multiplier 3

pvc 2/200

vbr-nrt 1980 1900

oam retry 3 3 1

encapsulation aal5snap

Page 41: MPLS  FastReRouting

protocol ip inarp

!

!

interface ATM1/1/0

no ip address

shutdown

no atm enable-ilmi-trap

!

interface GigabitEthernet2/1

description vs P_Core_02 1/2/1

dampening 30 1 362 255

mtu 2312

no ip address

ip ospf network point-to-point

shutdown

mpls ip

!

interface GigabitEthernet2/2

description vs P_CORE_03 G1/2/0

dampening 30 1 362 255

mtu 2312

ip address 10.150.3.10 255.255.255.252

ip ospf network point-to-point

mpls ip

bfd interval 50 min_rx 50 multiplier 3

!

interface GigabitEthernet3/48

switchport

Page 42: MPLS  FastReRouting

spanning-tree portfast

!

interface GigabitEthernet5/1

description vs P_Core_03 1/2/1

dampening 30 1 362 255

mtu 2312

ip address 10.100.3.10 255.255.255.252

ip ospf network point-to-point

shutdown

mpls ip

!

interface GigabitEthernet5/2

no ip address

shutdown

!

interface Vlan1

no ip address

shutdown

!

router ospf 1

router-id 10.150.100.5

ispf

log-adjacency-changes

auto-cost reference-bandwidth 10000

nsf

timers throttle spf 50 50 5000

timers lsa arrival 15

timers pacing flood 15

Page 43: MPLS  FastReRouting

network 10.150.3.8 0.0.0.3 area 0

network 10.150.100.5 0.0.0.0 area 0

bfd all-interfaces

!

router bgp 64600

no synchronization

bgp router-id 10.150.100.5

bgp log-neighbor-changes

bgp graceful-restart restart-time 120

bgp graceful-restart stalepath-time 360

bgp graceful-restart

timers bgp 6 18

neighbor 10.150.100.6 remote-as 64600

neighbor 10.150.100.6 description PE3

neighbor 10.150.100.6 update-source Loopback0

neighbor 10.150.100.6 fall-over bfd

neighbor 10.150.100.7 remote-as 64600

neighbor 10.150.100.7 description PE2

neighbor 10.150.100.7 update-source Loopback0

neighbor 10.150.100.7 fall-over bfd

no auto-summary

!

address-family vpnv4

neighbor 10.150.100.6 activate

neighbor 10.150.100.6 send-community extended

neighbor 10.150.100.7 activate

neighbor 10.150.100.7 send-community extended

exit-address-family

Page 44: MPLS  FastReRouting

!

address-family ipv4 vrf GEM

no synchronization

network 10.150.150.10 mask 255.255.255.255

redistribute connected

neighbor 10.150.50.2 remote-as 2043

neighbor 10.150.50.2 fall-over bfd

neighbor 10.150.50.2 activate

maximum-paths ibgp 2

exit-address-family

!

!

no ip http server

no ip http secure-server

!

!

mpls ldp router-id Loopback0 force

!

!

control-plane

!

alias exec ib show ip interface brief

!

line con 0

line vty 0 4

no login

transport input lat pad udptn telnet rlogin

!

Page 45: MPLS  FastReRouting

scheduler runtime netinput 300

!

end

Page 46: MPLS  FastReRouting

Configurazione PE2 PE2#

Current configuration : 7408 bytes

!

! Last configuration change at 13:50:57 UTC Fri Apr 29 2011

!

version 15.1

service timestamps debug uptime

service timestamps log uptime

service counters max age 10

!

hostname PE2

!

boot-start-marker

boot system flash disk0:c7600s72033-advipservices-mz.151-2.S.bin

boot-end-marker

!

!

!

no aaa new-model

!

!

!

ip source-route

!

ip vrf GEM

rd 10:12

Page 47: MPLS  FastReRouting

route-target export 10:10

route-target import 10:10

!

no ip domain lookup

!

!

!

!

vtp domain testplant

vtp mode transparent

mpls label protocol ldp

no mls flow ip

no mls flow ipv6

mls cef error action freeze

multilink bundle-name authenticated

!

!

!

spanning-tree mode pvst

no spanning-tree optimize bpdu transmission

spanning-tree extend system-id

diagnostic bootup level minimal

!

redundancy

main-cpu

auto-sync running-config

mode sso

!

Page 48: MPLS  FastReRouting

vlan internal allocation policy ascending

vlan access-log ratelimit 2000

!

!

!

!

!

!

!

interface Loopback0

ip address 10.150.100.7 255.255.255.255

!

interface Loopback100

ip vrf forwarding GEM

ip address 10.150.150.20 255.255.255.255

!

interface ATM1/0/0

mtu 1500

no ip address

logging event link-status

atm uni-version 3.1

no atm enable-ilmi-trap

no atm auto-configuration

no atm address-registration

no atm ilmi-enable

!

interface ATM1/0/0.102 point-to-point

ip vrf forwarding GEM

Page 49: MPLS  FastReRouting

ip address 10.150.50.13 255.255.255.252

no atm enable-ilmi-trap

pvc 2/102

vbr-nrt 1980 1900

oam retry 3 3 1

encapsulation aal5snap

!

!

interface ATM1/1/0

no ip address

shutdown

no atm enable-ilmi-trap

!

interface GigabitEthernet2/1

no ip address

shutdown

!

interface GigabitEthernet2/2

description vs P_CORE_01 G1/2/0

mtu 2312

ip address 10.150.3.2 255.255.255.252

ip ospf network point-to-point

mpls ip

bfd interval 50 min_rx 50 multiplier 3

!

!

router ospf 1

router-id 10.150.100.7

Page 50: MPLS  FastReRouting

ispf

auto-cost reference-bandwidth 10000

nsf

timers throttle spf 50 50 5000

timers throttle lsa 0 20 5000

timers lsa arrival 15

timers pacing flood 15

network 10.150.3.0 0.0.0.3 area 0

network 10.150.100.7 0.0.0.0 area 0

bfd all-interfaces

!

router bgp 64600

bgp router-id 10.150.100.7

bgp log-neighbor-changes

bgp graceful-restart restart-time 120

bgp graceful-restart stalepath-time 360

bgp graceful-restart

timers bgp 6 18

neighbor 10.150.100.5 remote-as 64600

neighbor 10.150.100.5 description PE1

neighbor 10.150.100.5 update-source Loopback0

neighbor 10.150.100.5 fall-over bfd

neighbor 10.150.100.6 remote-as 64600

neighbor 10.150.100.6 description PE3

neighbor 10.150.100.6 update-source Loopback0

neighbor 10.150.100.6 fall-over bfd

!

address-family vpnv4

Page 51: MPLS  FastReRouting

neighbor 10.150.100.5 activate

neighbor 10.150.100.5 send-community extended

neighbor 10.150.100.6 activate

neighbor 10.150.100.6 send-community extended

exit-address-family

!

address-family ipv4 vrf GEM

network 10.150.150.20 mask 255.255.255.255

redistribute connected

neighbor 10.150.50.14 remote-as 2036

neighbor 10.150.50.14 fall-over bfd

neighbor 10.150.50.14 activate

maximum-paths ibgp 2

exit-address-family

!

ip forward-protocol nd

!

no ip http server

!

logging esm config

!

mpls ldp router-id Loopback0 force

!

!

control-plane

!

alias exec ib show ip interface brief

!

Page 52: MPLS  FastReRouting

line con 0

line vty 0 4

no login

transport input lat pad udptn telnet rlogin

!

!

!

end

Page 53: MPLS  FastReRouting

Configurazione PE3 PE3#

Building configuration...

Current configuration : 8678 bytes

!

! Last configuration change at 17:01:16 GMT Fri Apr 29 2011

!

version 15.1

service timestamps debug datetime msec

service timestamps log datetime msec localtime

service counters max age 10

!

hostname PE3

!

boot-start-marker

boot system flash disk0:c7600s72033-advipservices-mz.151-2.S.bin

boot-end-marker

!

!

enable secret 5 $1$49nc$U3fiG6M9C2HAG9E7ZGR.r1

!

no aaa new-model

!

!

!

clock timezone GMT 1 0

clock summer-time GMT recurring

Page 54: MPLS  FastReRouting

ip source-route

!

ip vrf GEM

rd 10:10

route-target export 10:10

route-target import 10:10

!

no ip domain lookup

!

!

!

!

vtp domain testplant

vtp mode transparent

mpls label protocol ldp

mls ip cef load-sharing full

mls flow ip interface-full

no mls flow ipv6

mls qos

no mls acl tcam share-global

mls cef error action freeze

multilink bundle-name authenticated

!

!

!

spanning-tree mode pvst

no spanning-tree optimize bpdu transmission

spanning-tree extend system-id

Page 55: MPLS  FastReRouting

diagnostic bootup level minimal

no diagnostic cns publish

no diagnostic cns subscribe

!

redundancy

main-cpu

auto-sync running-config

mode sso

!

vlan internal allocation policy ascending

vlan access-log ratelimit 2000

!

ip tcp path-mtu-discovery age-timer 10

!

!

!

!

!

!

interface Loopback0

description Loopback per ospf

ip address 10.150.100.6 255.255.255.255

!

interface Loopback100

ip vrf forwarding GEM

ip address 10.150.150.30 255.255.255.255

!

interface ATM1/0/0

Page 56: MPLS  FastReRouting

mtu 1500

no ip address

logging event link-status

logging event atm pvc state

atm uni-version 3.1

no atm auto-configuration

no atm address-registration

no atm ilmi-enable

no atm enable-ilmi-trap

!

interface ATM1/0/0.100 point-to-point

ip vrf forwarding GEM

ip address 10.150.50.5 255.255.255.252

logging event subif-link-status

no atm enable-ilmi-trap

bfd interval 999 min_rx 999 multiplier 3

pvc 2/100

vbr-nrt 1980 1900

oam retry 3 3 1

encapsulation aal5snap

!

!

interface ATM1/0/0.101 point-to-point

ip vrf forwarding GEM

ip address 10.150.50.9 255.255.255.252

logging event subif-link-status

no atm enable-ilmi-trap

bfd interval 50 min_rx 50 multiplier 3

Page 57: MPLS  FastReRouting

pvc 2/101

vbr-nrt 1980 1900

oam retry 3 3 1

encapsulation aal5snap

!

!

interface ATM1/1/0

no ip address

shutdown

no atm enable-ilmi-trap

!

interface GigabitEthernet2/1

description vs P_Core_01 1/2/2

dampening 30 1 362 255

mtu 2312

no ip address

ip ospf network point-to-point

mpls ip

!

interface GigabitEthernet2/2

description vs P_CORE_03 G1/2/2

dampening 30 1 362 255

mtu 2312

ip address 10.150.3.14 255.255.255.252

ip ospf network point-to-point

mpls ip

bfd interval 50 min_rx 50 multiplier 3

!

Page 58: MPLS  FastReRouting

!

router ospf 1

router-id 10.150.100.6

ispf

auto-cost reference-bandwidth 10000

nsf

timers throttle spf 50 50 5000

timers throttle lsa 0 20 5000

timers lsa arrival 15

timers pacing flood 15

network 10.150.3.12 0.0.0.3 area 0

network 10.150.100.6 0.0.0.0 area 0

bfd all-interfaces

!

router bgp 64600

bgp router-id 10.150.100.6

bgp log-neighbor-changes

bgp graceful-restart restart-time 120

bgp graceful-restart stalepath-time 360

bgp graceful-restart

timers bgp 6 18

neighbor 10.150.100.5 remote-as 64600

neighbor 10.150.100.5 description PE1

neighbor 10.150.100.5 update-source Loopback0

neighbor 10.150.100.5 fall-over bfd

neighbor 10.150.100.7 remote-as 64600

neighbor 10.150.100.7 description PE2

neighbor 10.150.100.7 update-source Loopback0

Page 59: MPLS  FastReRouting

neighbor 10.150.100.7 fall-over bfd

!

address-family vpnv4

neighbor 10.150.100.5 activate

neighbor 10.150.100.5 send-community extended

neighbor 10.150.100.7 activate

neighbor 10.150.100.7 send-community extended

exit-address-family

!

address-family ipv4 vrf GEM

network 10.150.150.30 mask 255.255.255.255

redistribute connected

neighbor 10.150.50.6 remote-as 2043

neighbor 10.150.50.6 fall-over bfd

neighbor 10.150.50.6 activate

neighbor 10.150.50.10 remote-as 2036

neighbor 10.150.50.10 fall-over bfd

neighbor 10.150.50.10 activate

maximum-paths ibgp 2

exit-address-family

!

ip forward-protocol nd

!

no ip http server

ip route 0.0.0.0 0.0.0.0 10.150.0.1

!

logging esm config

!

Page 60: MPLS  FastReRouting

mpls ldp router-id Loopback0 force

!

!

control-plane

!

alias exec ib show ip interface brief

!

line con 0

line vty 0 4

no login

transport input lat pad udptn telnet rlogin

!

!

!

end

PE3#

Page 61: MPLS  FastReRouting

Configurazione PT NEW-PT#

Current configuration : 2490 bytes

!

! Last configuration change at 15:06:31 UTC Fri Apr 29 2011

!

version 15.0

service timestamps debug datetime msec

service timestamps log datetime msec

no service password-encryption

!

hostname NEW-PT

!

boot-start-marker

boot system flash flash:c2800nm-advipservicesk9-mz.150-1.M5.bin

warm-reboot

boot-end-marker

!

card type e1 1

!

no aaa new-model

!

!

!

no network-clock-participate slot 1

!

Page 62: MPLS  FastReRouting

dot11 syslog

ip source-route

!

!

ip cef

!

!

no ip domain lookup

no ipv6 cef

!

multilink bundle-name authenticated

!

frame-relay switching

!

!

!

!

!

!

!

!

!

voice-card 0

!

!

!

!

!

Page 63: MPLS  FastReRouting

license udi pid CISCO2811 sn FCZ102272ZY

!

redundancy

!

!

controller E1 1/0

clock source free-running

channel-group 1 timeslots 1-31

!

!

!

!

!

!

!

!

!

interface Loopback0

ip address 10.150.150.1 255.255.255.255

!

!

interface FastEthernet0/0

no ip address

shutdown

duplex auto

speed auto

!

!

Page 64: MPLS  FastReRouting

interface FastEthernet0/1

no ip address

shutdown

duplex auto

speed auto

!

!

interface Serial0/0/0

no ip address

shutdown

clock rate 2000000

!

!

interface BRI0/2/0

no ip address

encapsulation hdlc

shutdown

!

!

interface BRI0/3/0

no ip address

encapsulation hdlc

shutdown

!

!

interface Serial1/0:1

bandwidth 2048

no ip address

Page 65: MPLS  FastReRouting

encapsulation frame-relay IETF

logging event subif-link-status

logging event dlci-status-change

no fair-queue

frame-relay traffic-shaping

frame-relay lmi-type ansi

!

!

interface Serial1/0:1.43 point-to-point

ip address 10.150.50.2 255.255.255.252

bfd interval 999 min_rx 999 multiplier 3

frame-relay interface-dlci 43

!

interface Serial1/0:1.44 point-to-point

ip address 10.150.50.6 255.255.255.252

bfd interval 999 min_rx 999 multiplier 3

frame-relay interface-dlci 44

!

router bgp 2043

no synchronization

bgp router-id 10.150.150.1

bgp log-neighbor-changes

bgp graceful-restart restart-time 120

bgp graceful-restart stalepath-time 360

bgp graceful-restart

network 10.150.150.1 mask 255.255.255.255

timers bgp 6 18

neighbor 10.150.50.1 remote-as 64600

Page 66: MPLS  FastReRouting

neighbor 10.150.50.1 description PE1

neighbor 10.150.50.1 fall-over bfd

neighbor 10.150.50.5 remote-as 64600

neighbor 10.150.50.5 description PE3

neighbor 10.150.50.5 fall-over bfd

maximum-paths 2

no auto-summary

!

ip forward-protocol nd

ip http server

no ip http secure-server

!

!

!

!

!

!

!

!

!

control-plane

!

!

!

!

!

!

!

Page 67: MPLS  FastReRouting

!

alias exec ib show ip interface brief

!

line con 0

line aux 0

line vty 0 4

password cisco

login

transport input all

!

scheduler allocate 20000 1000

end

Page 68: MPLS  FastReRouting

Configurazione PPA PPA#sh run

Building configuration...

Current configuration : 2489 bytes

!

! Last configuration change at 15:45:51 UTC Fri Apr 29 2011

version 15.1

service timestamps debug datetime msec

service timestamps log datetime msec

no service password-encryption

!

hostname PPA

!

boot-start-marker

boot system flash flash:c2800nm-advipservicesk9-mz.151-4.M.bin

warm-reboot

boot-end-marker

!

!

enable password cisco

!

no aaa new-model

!

!

dot11 syslog

ip source-route

Page 69: MPLS  FastReRouting

!

!

ip cef

!

!

!

no ip domain lookup

no ipv6 cef

!

multilink bundle-name authenticated

!

!

!

!

!

!

!

!

!

!

!

voice-card 0

!

crypto pki token default removal timeout 0

!

!

!

!

Page 70: MPLS  FastReRouting

license udi pid CISCO2821 sn FCZ102273RG

!

redundancy

!

!

!

!

!

!

!

!

!

!

interface Loopback0

ip address 10.150.150.2 255.255.255.255

!

interface GigabitEthernet0/0

ip address 10.2.2.1 255.255.255.0

duplex auto

speed auto

!

interface GigabitEthernet0/1

no ip address

shutdown

duplex auto

speed auto

!

interface Serial0/0/0

Page 71: MPLS  FastReRouting

no ip address

!

interface Serial0/1/0

no ip address

shutdown

clock rate 125000

!

interface Serial0/1/1

no ip address

shutdown

clock rate 125000

!

interface ATM0/3/0

no ip address

shutdown

no atm ilmi-keepalive

!

interface ATM1/0

mtu 1500

no ip address

atm uni-version 3.1

no atm auto-configuration

no atm ilmi-keepalive

no atm address-registration

no atm ilmi-enable

no atm enable-ilmi-trap

!

interface ATM1/0.101 point-to-point

Page 72: MPLS  FastReRouting

ip address 10.150.50.10 255.255.255.252

no atm enable-ilmi-trap

pvc 2/101

vbr-nrt 1980 1900

oam retry 3 3 1

encapsulation aal5snap

!

!

interface ATM1/0.102 point-to-point

ip address 10.150.50.14 255.255.255.252

no atm enable-ilmi-trap

pvc 2/102

vbr-nrt 1980 1900

oam retry 3 3 1

encapsulation aal5snap

!

!

router bgp 2036

bgp router-id 10.150.150.2

bgp log-neighbor-changes

bgp graceful-restart restart-time 120

bgp graceful-restart stalepath-time 360

bgp graceful-restart

network 10.150.150.2 mask 255.255.255.255

timers bgp 6 18

redistribute connected

neighbor 10.150.50.9 remote-as 64600

neighbor 10.150.50.9 description PE3

Page 73: MPLS  FastReRouting

neighbor 10.150.50.13 remote-as 64600

neighbor 10.150.50.13 description PE2

maximum-paths 2

!

ip forward-protocol nd

ip http server

no ip http secure-server

!

!

ip route 10.1.1.0 255.255.255.0 192.168.1.2

!

logging esm config

!

!

!

!

!

!

control-plane

!

!

!

!

mgcp profile default

!

!

!

!

Page 74: MPLS  FastReRouting

!

alias exec ib show ip interface brief

!

line con 0

line aux 0

line vty 0

password cisco

login

transport input all

line vty 1 4

login

transport input all

!

scheduler allocate 20000 1000

end

Page 75: MPLS  FastReRouting

Configurazione MSR8540 ATM-SWITCH ATM_SWITCH#

ATM_SWITCH#sh run

Building configuration...

Current configuration : 3309 bytes

!

version 12.1

no service pad

service timestamps debug uptime

service timestamps log uptime

no service password-encryption

!

hostname ATM_SWITCH

!

boot system flash bootflash:cat8510m-wp-mz.121-27b.E.bin

!

sdm ipqos zero

sdm policy 0

ip subnet-zero

no ip domain-lookup

!

!

atm routing-mode static

atm address 47.0091.8100.0000.000d.65a9.f501.000d.65a9.f501.00

!

controller E1 0/1/0

clock source network-derived

Page 76: MPLS  FastReRouting

!

controller E1 0/1/1

!

controller E1 0/1/2

!

controller E1 0/1/3

clock source free-running

channel-group 1 timeslots 1-31

!

controller E1 1/1/0

!

controller E1 1/1/1

!

controller E1 1/1/2

!

controller E1 1/1/3

!

!

!

interface ATM0/0/0

no ip address

no atm auto-configuration

ATM_SWITCH#term len 0

ATM_SWITCH#sh run

Building configuration...

Current configuration : 3309 bytes

Page 77: MPLS  FastReRouting

!

version 12.1

no service pad

service timestamps debug uptime

service timestamps log uptime

no service password-encryption

!

hostname ATM_SWITCH

!

boot system flash bootflash:cat8510m-wp-mz.121-27b.E.bin

!

sdm ipqos zero

sdm policy 0

ip subnet-zero

no ip domain-lookup

!

!

atm routing-mode static

atm address 47.0091.8100.0000.000d.65a9.f501.000d.65a9.f501.00

!

controller E1 0/1/0

clock source network-derived

!

controller E1 0/1/1

!

controller E1 0/1/2

!

controller E1 0/1/3

Page 78: MPLS  FastReRouting

clock source free-running

channel-group 1 timeslots 1-31

!

controller E1 1/1/0

!

controller E1 1/1/1

!

controller E1 1/1/2

!

controller E1 1/1/3

!

!

!

interface ATM0/0/0

no ip address

no atm auto-configuration

no atm ilmi-keepalive

atm uni version 3.1

!

interface ATM0/0/1

no ip address

no atm auto-configuration

no atm ilmi-keepalive

no atm address-registration

no atm ilmi-enable

atm uni version 3.1

!

interface ATM0/0/2

Page 79: MPLS  FastReRouting

no ip address

no atm auto-configuration

no atm ilmi-keepalive

no atm address-registration

no atm ilmi-enable

atm uni version 3.1

!

interface ATM0/0/3

no ip address

!

interface Serial0/1/3:1

no ip address

encapsulation frame-relay IETF

no arp frame-relay

frame-relay lmi-type ansi

frame-relay pvc 43 service translation interface ATM1/0/0 2 200

atm oam interface ATM1/0/0 2 200 ais rdi

frame-relay pvc 44 service translation interface ATM1/0/1 2 100

atm oam interface ATM1/0/1 2 100 ais rdi

frame-relay intf-type dce

!

interface ATM1/0/0

no ip address

no atm auto-configuration

no atm ilmi-keepalive

no atm address-registration

no atm ilmi-enable

atm uni version 3.1

Page 80: MPLS  FastReRouting

!

interface ATM1/0/1

no ip address

no atm auto-configuration

no atm ilmi-keepalive

no atm address-registration

no atm ilmi-enable

atm uni version 3.1

atm pvc 2 101 interface ATM0/0/1 2 101

!

interface ATM1/0/2

no ip address

no atm auto-configuration

no atm ilmi-keepalive

no atm address-registration

no atm ilmi-enable

atm uni version 3.1

atm pvc 2 102 interface ATM0/0/1 2 102

!

interface ATM1/0/3

no ip address

!

interface ATM0

no ip address

atm oam interface ATM0/0/0 0 16 seg-loopback end-loopback rdi

atm oam interface ATM0/0/1 0 16 seg-loopback end-loopback rdi

atm oam interface ATM0/0/2 0 16 seg-loopback end-loopback rdi

atm oam interface ATM0/0/3 0 16 seg-loopback end-loopback rdi

Page 81: MPLS  FastReRouting

atm oam interface ATM1/0/0 0 16 seg-loopback end-loopback rdi

atm oam interface ATM1/0/1 0 16 seg-loopback end-loopback rdi

atm oam interface ATM1/0/2 0 16 seg-loopback end-loopback rdi

atm oam interface ATM1/0/3 0 16 seg-loopback end-loopback rdi

atm oam interface ATM0/0/0 0 5 seg-loopback end-loopback rdi

atm oam interface ATM0/0/1 0 5 seg-loopback end-loopback rdi

atm oam interface ATM0/0/2 0 5 seg-loopback end-loopback rdi

atm oam interface ATM0/0/3 0 5 seg-loopback end-loopback rdi

atm oam interface ATM1/0/0 0 5 seg-loopback end-loopback rdi

atm oam interface ATM1/0/1 0 5 seg-loopback end-loopback rdi

atm oam interface ATM1/0/2 0 5 seg-loopback end-loopback rdi

atm oam interface ATM1/0/3 0 5 seg-loopback end-loopback rdi

!

interface Ethernet0

no ip address

!

ip classless

no ip http server

!

!

alias exec ib show ip interface brief

!

line con 0

line aux 0

line vty 0 4

login

!

!

Page 82: MPLS  FastReRouting

end

ATM_SWITCH#