Async Multilink PPP da router a router

Introduzione

Questa configurazione descrive un Cisco 3640 remoto con una scheda modem analogica a 8 porte (NM-8AM) interna che si connette a un Cisco AS5300 con una Primary Rate Interface (PRI). La configurazione descrive una connessione multipla composta da due linee telefoniche analogiche sul sito remoto. È possibile configurare più linee telefoniche per MP, se disponibili.

Prerequisiti

Requisiti

Non sono previsti prerequisiti specifici per questo documento.

Componenti usati

Le informazioni fornite in questo documento si basano sulle versioni software e hardware riportate di seguito.

• Cisco 3640 con software Cisco IOS versione 12.1(3)

• Cisco AS5300 con software Cisco IOS versione 12.07(T)

Nota: MP è stato introdotto per la prima volta nel software Cisco IOS versione 11.0(3).

Le informazioni discusse in questo documento fanno riferimento a dispositivi usati in uno specifico ambiente di emulazione. Su tutti i dispositivi menzionati nel documento la configurazione è stata ripristinata ai valori predefiniti. Se la rete è operativa, valutare attentamente eventuali conseguenze derivanti dall'uso dei comandi.

Convenzioni

Per ulteriori informazioni sulle convenzioni usate, consultare il documento Cisco sulle convenzioni nei suggerimenti tecnici.

Nozioni di base

Multilink PPP (MP) consente ai dispositivi di inviare dati su più collegamenti dati point-to-point alla stessa destinazione implementando un collegamento virtuale. La larghezza di banda massima della connessione MP è uguale alla somma delle larghezze di banda dei collegamenti dei componenti. MP può essere configurato sia per i collegamenti multiplex, come ISDN e Frame Relay, sia per più linee asincrone. Per ulteriori informazioni su MP, consultare la RFC 1990 .

Nota: la RFC 1990 fa riferimento al protocollo Multilink PPP come protocollo MP. Altri nomi noti per MP sono MPPP, MLP e Multilink.

Async MP può essere utilizzato per collegare i client remoti a una velocità superiore a quella disponibile attraverso una singola connessione analogica. In Async MP, il client remoto utilizza più modem, e quindi più linee telefoniche, per connettersi al router centrale e accedere alla rete. Poiché più linee telefoniche sono spesso più economiche rispetto al servizio BRI (Basic Rate Interface) ISDN, Async MP offre un modo efficace per aumentare la velocità di connessione per gli utenti remoti e controllare i costi. Async MP è anche un modo efficace per ottenere velocità di accesso più elevate per le aree remote che non possono essere servite da ISDN.

Async MP raggruppa le connessioni modem separate a un Access Server. Il software PPP su ciascun peer frammenta i pacchetti e quindi trasmette i pacchetti all'altro lato tramite le diverse connessioni analogiche. L'estremità ricevente raccoglie questi pezzi dalle connessioni separate e, sulla base delle informazioni MP in essi incorporate, li ricompone in pacchetti di dati validi, fornendo così un collegamento virtuale end-to-end con una larghezza di banda maggiore. Il protocollo MP asincrono può essere configurato tra due router o tra un router e un PC client.

Configurazione

In questa sezione vengono presentate le informazioni necessarie per configurare le funzionalità descritte più avanti nel documento.

Nota: per ulteriori informazioni sui comandi menzionati in questo documento, usare lo strumento di ricerca dei comandi

Esempio di rete

Questo documento utilizza le impostazioni di rete mostrate nel diagramma sottostante.

Configurazioni

Questo documento utilizza le configurazioni mostrate di seguito.

• Cisco 3640

• Cisco AS5300

clearlake-lan-01#show runnning-config
Building configuration...

Current configuration:
!
version 12.1
service timestamps debug datetime msec localtime show-timezone
service timestamps log datetime msec localtime show-timezone
!
hostname clearlake-lan-01
!
aaa new-model
aaa authentication login default local
aaa authentication ppp default if-needed local
!
username bobslake-nas-01 password <deleted>

!--- Remote router and password for CHAP authentication. !--- Dialer interface must also be configured to use !--- this username and password.

username admin privilege 15 password <deleted>
!         
no ip domain-lookup
!
chat-script async-mppp ABORT ERROR ABORT BUSY 
"" "ATZ" OK "ATDT \T" TIMEOUT 30 CONNECT \c

!--- Chat script used for dialing out.

!
interface Loopback0
 ip address 172.21.126.254 255.255.255.0
!
interface Ethernet0/0
 ip address 172.21.125.1 255.255.255.0
!
interface Group-Async1

!--- Interface to configure modems used for dialout.

 no ip address
 encapsulation ppp

!--- Use PPP encapsulation for members of this !--- group-async interface.

 dialer in-band

!--- Permit DDR on this interface.

 dialer pool-member 10

!--- All members of this group-async interface belong !--- to dialer pool 10.

 ppp multilink

!--- Enable PPP multilink on physical interface.

 group-range 33 34

!--- Assign async 33 and 34 to this group-async interface. !--- This can be adjusted depending on the number of POTS lines available.

! 
 interface Dialer1

!--- Dialer interface to dialout to bobslake-nas-01.

 ip address negotiated

!--- Obtain an IP address from central site.

 encapsulation ppp
 dialer remote-name bobslake-nas-01

!--- Identify central site router for CHAP authentication. !--- Shared secret password is defined above.

 dialer pool 10

!--- Defines the pool of physical resources that the Dialer !--- interface may use.

 dialer idle-timeout 600

!--- Specifies number of seconds without interesting traffic that !--- the connection is kept up.

 dialer string 5551212

!--- Number to be dialed; this number belongs to the PRI !--- of the central router.

 dialer load-threshold 15 either

!--- Load level for either inbound or outbound traffic !--- at which additional lines will be added to the MP bundle. !--- Load level values range from 1 (unloaded) to 255 (fully loaded).

 dialer-group 8

!--- Uses dialer-list 8 to determine interesting traffic.

 ppp authentication chap callin

!--- Use CHAP authentication for incoming calls only !--- This router will not challenge remote routers for outgoing calls.

 ppp multilink

!--- Activates the interface for MP operation.

 ppp timeout multilink link remove 300

!--- Keeps the multilink connections up for 300 seconds !--- after the load drops below the threshold. !--- This command should be used to control flapping.

!
ip classless
ip route 0.0.0.0 0.0.0.0 Dialer1

!--- Use Interface Dialer1 for all networks.

no ip http server
!
access-list 188 remark define interesting traffic
access-list 188 deny   udp any any eq ntp
access-list 188 permit ip any any
dialer-list 8 protocol ip list 188

!--- Assign access-list 188 to dialer-list 8. 

!
line con 0
 transport input none
line 33 34

!--- Async lines to be used for dialout. !--- This number should match the group-range in the !--- Group-Async interface.

 script dialer async-mppp

!--- Use chat script called async-mppp for dialout.

 modem InOut
 modem autoconfigure discovery
 transport preferred none
 transport input all
line 35 40
 transport preferred none
 transport input all
line aux 0
line vty 0 4
!
ntp clock-period 17179871
ntp server 172.22.255.1 prefer
end

bobslake-nas-01#show running-config 

Building configuration...

Current configuration:
  
version 12.0
service timestamps debug datetime msec localtime show-timezone
service timestamps log datetime msec localtime show-timezone
service password-encryption
service tcp-small-servers
!
hostname bobslake-nas-01
!
logging buffered 10000 debugging
aaa new-model
aaa authentication login default local
aaa authentication ppp default if-needed local

!--- Authenticate for PPP if not authenticated during login. !--- Allows users with Terminal Window after Dial to initiate PPP.

!
username clearlake-lan-01 password <deleted>

!--- Remote router and password for Challenge Handshake !--- Authentication Protocol (CHAP) authentication. !--- The password must be identical on both sides.

spe 1/0 1/7
firmware location system:/ucode/mica_port_firmware
!
resource-pool disable
!
ip subnet-zero
!
multilink virtual-template 1

!--- Use virtual-template 1 for multilink connections.

isdn switch-type primary-5ess
isdn voice-call-failure 0
!
controller T1 0
 framing esf
 clock source line primary
 linecode b8zs
 pri-group timeslots 1-24
!
 interface Loopback0
  ip address 172.21.10.10 255.255.255.255
  no ip directed-broadcast
!
interface Loopback1
 ip address 172.21.104.254 255.255.255.0

!--- Summarizes addresses in address pool. !--- Loopback 1 is in the same subnet as the address pool.

 no ip directed-broadcast
!
 interface Virtual-Template1
 description Template for Multilink Users
 ip unnumbered Loopback0 
 no ip directed-broadcast
 peer default ip address pool addr-pool

!--- Use IP pool called addr-pool for incoming calls.

 ppp authentication chap

!--- Authenticate using CHAP.

 ppp multilink

!--- Allow multilink sessions.

!

!--- Configure D channel on PRI.

interface Serial0:23
 description Headquarters 555-1212 active PRI line
 no ip address
 no ip directed-broadcast
 isdn switch-type primary-5ess
 isdn incoming-voice mode
 fair-queue 64 256 0
 no cdp enable
!
interface FastEthernet0
 ip address 172.21.101.23 255.255.255.0
 no ip directed-broadcast
 duplex auto
 speed auto
!
interface Group-Async1
 ip unnumbered Loopback0
 no ip directed-broadcast
 encapsulation ppp
 dialer in-band
 dialer idle-timeout 600 either

!--- Specifies number of seconds without interesting !--- traffic that the connection is kept up. !--- Configure the same idle-timeout on both routers.

 dialer map ip 172.21.125.1 name clearlake-nas-01
 dialer-group 5

!--- Uses dialer-list 5 to determine interesting traffic.

 async mode interactive
 peer default ip address pool addr-pool

!--- Use IP pool called addr-pool for incoming calls.

 ppp authentication chap callin

!--- Issue CHAP challenges for dialin users only. 

ppp multilink
 group-range 1 48

!--- Assign modems 1-48 to the Group-Async 1 configuration template.

! 
 router eigrp 1
 passive-interface Group-Async1

!--- To prevent routing traffic on async lines. 

 network 172.21.0.0
!
ip local pool addr-pool 172.21.104.1 172.21.104.48

!--- Define IP address pool range for dialin clients.
 
ip classless
no ip http server
!
access-list 105 permit ip any any

!--- Define interesting traffic.

dialer-list 5 protocol ip list 105

!--- Assign access list 105 to dialer list 5.

!
line con 0
 transport input none
line 1 48
 autoselect during-login

!--- Permits user login prompts after dialin.

 autoselect ppp

!--- Automatically launches PPP on the line.

 modem InOut

!--- Modems can be used to dialin and dialout.

 transport preferred none
 transport output telnet
line aux 0
line vty 0 4
!
ntp clock-period 17180374
ntp update-calendar
ntp server 172.22.255.1 prefer
end

Comandi di ottimizzazione e opzionali

I comandi seguenti possono essere utilizzati per regolare il comportamento della connessione MP. Un'attenta regolazione di tali parametri può aiutare a controllare i costi evitando un uso inutile e dispendioso dei collegamenti dati.

• dialer load-threshold load [in uscita] | in entrata | oppure]

  È possibile configurare MP in modo che i canali aggiuntivi vengano visualizzati immediatamente dopo aver stabilito il canale principale. Per impostare questo scenario, impostare il valore della soglia di carico nel comando load-thershold load della connessione telefonica su 1. In questo caso, i canali aggiuntivi vengono attivati e continuano a rimanere attivi (ovvero non flap). Se la soglia di carico è impostata su un qualsiasi altro valore, i canali multipli possono lampeggiare a seconda del carico sul collegamento. Se si desidera aggiungere ulteriori canali, in base al traffico, impostare la soglia di carico sul valore appropriato tra 1 e 255. Ad esempio, per visualizzare ulteriori canali al 50%, la soglia deve essere impostata su 128 (0,50*255). Quando si determina la soglia, è necessario considerare il tempo di impostazione per le chiamate asincrone perché tempi di impostazione più lunghi potrebbero richiedere soglie inferiori.

  Il carico può essere calcolato in base al valore in uscita, in entrata o al valore più alto tra il traffico in entrata e in uscita sull'interfaccia. Se il carico viene basato sul traffico in entrata o su uno dei due, verificare che nel sito centrale sia configurata l'interfaccia passiva Group-Async1, in modo che gli aggiornamenti del routing dal core non vengano inviati tramite la linea asincrona. Impedire al traffico di routing di passare sul collegamento fornisce maggiore larghezza di banda per altri dati sulla linea.

• timeout ppp collegamento multiplo rimozione secondi

  Questo comando può essere utilizzato per impedire che le connessioni a connessione multipla lampeggino quando il carico varia. Ad esempio, quando la soglia di carico è impostata su 15 (ovvero 15/255=6%) e il traffico supera la soglia, vengono visualizzate altre linee. Quando il traffico scende sotto la soglia, le linee aggiuntive vengono scartate. In situazioni in cui le velocità di trasmissione dei dati sono molto variabili, è vantaggioso che i canali multipli rimangano attivi per un determinato periodo di tempo anche se la soglia di carico scende al di sotto del valore specificato. Assegnare questo timeout di connessione multipla a un valore inferiore a quello specificato per il timeout di inattività della connessione telefonica che controlla il timeout per tutti i collegamenti.

• aggiunta di secondi per il collegamento multiplo timeout ppp

  Questo comando può essere utilizzato per impedire l'aggiunta di più collegamenti al bundle MP fino a quando non si riceve un traffico elevato per un intervallo specificato. In questo modo è possibile evitare che alcuni picchi di traffico causino inutilmente l'aumento delle linee.

Verifica

Le informazioni contenute in questa sezione permettono di verificare che la configurazione funzioni correttamente.

Alcuni comandi show sono supportati dallo strumento Output Interpreter, che consente di visualizzare un'analisi dell'output del comando show.

• show ppp multilink: consente di visualizzare informazioni sui bundle di connessione multipla attivi. Utilizzare questo comando per verificare la connessione multipla.

• show caller: consente di visualizzare informazioni sui singoli utenti e sulle risorse utilizzate sul NAS. Questo comando visualizza le statistiche delle chiamate attive per ampi pool di connessioni e mostra i tempi di inattività e assoluti per ciascun utente. Se la versione del software Cisco IOS in uso non supporta questo comando, utilizzare il comando show user.

• show caller user: consente di visualizzare i parametri per l'utente specifico, ad esempio la linea TTY utilizzata, l'interfaccia asincrona (scaffale/slot/porta), il numero del canale DS0, il numero del modem, l'indirizzo IP assegnato, i parametri del bundle PPP e PPP e così via. Se la versione in uso del software Cisco IOS non supporta questo comando, usare il comando show user.

Output di esempio

Gli output del comando show riportati di seguito sono tratti dallo switch Cisco 3640 che sta chiamando l'AS5300. Ciò indica che la connessione multilink è attiva

clearlake-lan-01#show ppp multilink
Virtual-Access1, bundle name is bobslake-nas-01

!--- Virtualized MP bundle. Bundle name is derived from the !--- username used during authentication.

  Dialer interface is Dialer1

!--- This Virtual Access Interface used Interface Dialer1.

  0 lost fragments, 0 reordered, 0 unassigned
  0 discarded, 0 lost received, 1/255 load
  0x4 received sequence, 0x0 sent sequence
  Member links: 2 (max not set, min not set)
    Async34
    Async33

!--- Members of the MP bundle.


clearlake-lan-01#show dialer


As33 - dialer type = IN-BAND ASYNC NO-PARITY
Dialer pool 10, priority 0

!--- Member of dialer pool 10.

Idle timer (120 secs), Fast idle timer (20 secs)
Wait for carrier (30 secs), Re-enable (15 secs)
Dialer state is multilink member
Dial reason: Multilink bundle overloaded

!--- Interface was not the first link in the MP bundle. 

Interface bound to profile Di1
Current call connected 00:00:54

!--- Current call duration

Connected to <deleted>5551212 (bobslake-nas-01) 

!--- Phone number that was dialed.


As34 - dialer type = IN-BAND ASYNC NO-PARITY
Dialer pool 10, priority 0

!--- Member of dialer pool 10.

Idle timer (600 secs), Fast idle timer (20 secs)
Wait for carrier (30 secs), Re-enable (15 secs)
Dialer state is multilink member
Dial reason: ip (s=172.21.125.1, d=172.21.104.254)

!--- Interface was the first link in the bundle, triggered by !--- interesting traffic.

Interface bound to profile Di1
Current call connected 00:00:54

!--- Current Call duration.

Connected to 5551212 <deleted> (bobslake-nas-01)

!--- Phone number that was dialed.


Gr1 - dialer type = IN-BAND ASYNC NO-PARITY
Idle timer (120 secs), Fast idle timer (20 secs)
Wait for carrier (30 secs), Re-enable (15 secs)
Dialer state is idle


Dial String      Successes   Failures    Last DNIS   Last status

Di1 - dialer type = DIALER PROFILE
Load threshold for dialing additional calls is 15

!--- Load threshold.

Idle timer (600 secs), Fast idle timer (20 secs)
Wait for carrier (30 secs), Re-enable (15 secs)
Dialer state is data link layer up
Number of active calls = 2

Dial String      Successes   Failures    Last DNIS   Last status
            15          0    00:00:56       successful   Default
clearlake-lan-01#show caller
                                                Active    Idle
  Line         User               Service       Time      Time
  con 0        tarpon             TTY           00:09:11  00:00:00  
  tty 33       -                  Async         -         00:00:01  
  TTY 34       -                  Async         -         00:00:06  
  As33         bobslake-nas-01    PPP           00:00:24  00:00:00  

!--- Second connection.

  As34         bobslake-nas-01    PPP           00:01:05  00:00:00  

!--- First connection. 

  Vi1          bobslake-nas-01    PPP   Bundle  00:01:05  00:01:04  

!--- MP bundle !--- bobslake-nas-01 has two async lines, two TTY, and one virtual !--- interface bundle.


clearlake-lan-01#show caller user bobslake-nas-01

  User: bobslake-nas-01, line As33, service PPP

!--- PPP setting for bobslake-nas-01.

        Active time 00:00:34, Idle time 00:00:00
  Timeouts:            Absolute  Idle
      Limits:          -         -         
      Disconnect in:   -         -         
  PPP: LCP Open, multilink Open, CHAP (-> AAA)

!--- Multilink is up.

  Dialer: Connected 00:01:09 to <deleted>, outbound

!--- Dialer interface was used to dialout.

          Type is IN-BAND ASYNC, group Dialer1
          Cause: Multilink bundle overloaded

!--- This interface was not the first member of the MP bundle.

  IP: Local 172.21.104.48/32
  Bundle: Member of bobslake-nas-01, last input 00:00:00
  Counts: 59 packets input, 3529 bytes, 0 no buffer
          0 input errors, 22 CRC, 0 frame, 0 overrun
          31 packets output, 1515 bytes, 0 underruns
          0 output errors, 0 collisions, 4 interface resets

!--- Packets are passing through the connection.


  User: bobslake-nas-01, line As34, service PPP

!--- PPP setting for user bobslake-nas-01.

        Active time 00:01:15, Idle time 00:00:00
  Timeouts:            Absolute  Idle
      Limits:          -         -         
      Disconnect in:   -         -         
  PPP: LCP Open, multilink Open, CHAP (-> AAA)

!--- MP state is open.

  Dialer: Connected 00:01:10 to <deleted>, outbound
          Type is IN-BAND ASYNC, group Dialer1
          Cause: ip (s=172.21.125.1, d=172.21.104.254)

!--- Dialing cause was interesting traffic; this was the !--- first link in the bundle.

  IP: Local 172.21.104.48/32
  Bundle: Member of bobslake-nas-01, last input 00:00:00
  Counts: 172 packets input, 20699 bytes, 0 no buffer
          0 input errors, 81 CRC, 0 frame, 0 overrun
          80 packets output, 14347 bytes, 0 underruns
          0 output errors, 0 collisions, 6 interface resets

!--- Packets are passing through the connection.


  User: bobslake-nas-01, line Vi1, service PPP Bundle

!--- Bundle information for user bobslake-nas-01.

        Active time 00:01:16, Idle time 00:01:15
  Timeouts:            Absolute  Idle
      Limits:          -         00:10:00  
      Disconnect in:   -         00:08:44  

!--- Idle-timeout is 600 seconds(10 minutes).

  PPP: LCP Open, multilink Open, IPCP
  Dialer: Connected 00:01:10 to <deleted>, outbound
          Idle timer 600 secs, idle 75 secs
          Type is IN-BAND SYNC, group Dialer1
  IP: Local 172.21.104.48/32, remote 172.21.104.254

!--- IP address assigned to the bundle and loopback address !--- of the remote router.

  Bundle: First link of bobslake-nas-01, 2 links, last input 00:01:16
  Counts: 23 packets input, 4758 bytes, 0 no buffer
          0 input errors, 0 CRC, 0 frame, 0 overrun
          7 packets output, 3734 bytes, 0 underruns
          0 output errors, 0 collisions, 0 interface resets

Di seguito sono riportati alcuni output del comando show dell'AS5300. Per ulteriori informazioni sugli output, consultare il documento Async Multilink PPP Dialup from Microsoft Windows Clients. L'output show e debug del sistema AS5300 (sito centrale) sarà simile a quello dei protocolli Async MP di PC-Router e Async MP di Router-Router.

bobslake-nas-01#show ppp multilink

Virtual-Access1, bundle name is clearlake-lan-01
  0 lost fragments, 0 reordered, 0 unassigned, sequence 0x1/0x10 rcvd/sent
  0 discarded, 0 lost received, 1/255 load
  Member links: 2 (max not set, min not set)
    Async47
    Async45

bobslake-nas-01#show caller
                                                Active    Idle
  Line         User               Service       Time      Time
  TTY 45       clearlake-lan-01   Async         00:01:12  00:01:03  
  TTY 47       clearlake-lan-01   Async         00:01:51  00:00:06  
  vty 0        admin              VTY           00:11:02  00:00:00  
  As45         clearlake-lan-01   PPP           00:01:02  00:00:00  
  As47         clearlake-lan-01   PPP           00:01:49  00:00:00  
  Vi1          clearlake-lan-01   PPP   Bundle  00:01:43  00:01:10  

Risoluzione dei problemi

Le informazioni contenute in questa sezione permettono di risolvere i problemi relativi alla configurazione.

Procedura di risoluzione dei problemi

Per la risoluzione dei problemi di una connessione MP, procedere come segue:

Di seguito è riportato un esempio di output del comando debug, contrassegnato con le spiegazioni su cosa cercare.

Quando si esegue il test della configurazione MP, assicurarsi di generare una quantità di traffico sufficiente sul collegamento per attivare la soglia di carico. Se necessario, potete regolare il valore della soglia di carico durante il test.

1. Utilizzare i comandi debug dialer e debug chat per verificare che la composizione della connessione sia corretta.

2. Verificare che la negoziazione e l'autenticazione PPP abbiano esito positivo. Prestare attenzione alla negoziazione LCP in cui vengono negoziati i parametri della riga MRRU (Maximum Receive Reconstruction Unit) e Discriminatore endpoint (EndpointDisc).

3. Verificare che il collegamento sia virtualizzato correttamente. Il software Cisco IOS crea un'interfaccia di accesso virtuale che rappresenta il bundle MP.

4. Verificare che la negoziazione IPCP (Internet Protocol Control Protocol) sia stata completata. Si noti se sono stati assegnati indirizzi IP corretti e se sono state installate le route corrette.

Comandi per la risoluzione dei problemi

Alcuni comandi show sono supportati dallo strumento Output Interpreter, che consente di visualizzare un'analisi dell'output del comando show.

Nota: prima di usare i comandi di debug, consultare le informazioni importanti sui comandi di debug.

• debug vtemplate: per visualizzare le informazioni di copia di un'interfaccia di accesso virtuale dal momento della copia da un modello virtuale al momento della disattivazione.

• debug ppp multilink events: consente di visualizzare informazioni sugli eventi che influiscono sui bundle multilink.

• debug ppp negotiation: per visualizzare le informazioni sul traffico e gli scambi PPP durante la negoziazione del protocollo LCP (Link Control Protocol), dell'autenticazione e del protocollo NCP (Network Control Protocol). Una negoziazione PPP riuscita aprirà innanzitutto lo stato LCP, quindi autenticherà e infine negozierà NCP. Durante la negoziazione LCP vengono stabiliti parametri di connessione multipla, ad esempio Unità massima di ricezione ricostruita (MRRU).

• debug ppp authentication: consente di visualizzare i messaggi del protocollo di autenticazione PPP, inclusi gli scambi di pacchetti Challenge Handshake Authentication Protocol (CHAP) e gli scambi PAP (Password Authentication Protocol).

• debug ppp error: consente di visualizzare gli errori di protocollo e le statistiche sugli errori associate alla negoziazione e al funzionamento della connessione PPP.

• debug modem - Per visualizzare l'attività della linea del modem su un server di accesso.

Output di esempio del comando debug

Il Cisco 3640 ha restituito le seguenti uscite. Mostrano il Cisco 3640 che chiama il sistema PRI dell'AS5300 e che stabilisce una connessione MP. Per un esempio dell'output del comando debug di AS5300, fare riferimento al documento Async Multilink PPP Dialup from Microsoft Windows Clients.

clearlake-lan-01#debug dialer
Dial on demand events debugging is on
clearlake-lan-01#debug ppp negotiation
PPP protocol negotiation debugging is on
clearlake-lan-01#debug ppp authentication 
PPP authentication debugging is on
clearlake-lan-01#debug vtemplate 
Virtual Template debugging is on
clearlake-lan-01#debug ppp multilink events
clearlake-lan-01#show debug
Dial on demand:
  Dial on demand events debugging is on
PPP:
  PPP authentication debugging is on
  PPP protocol negotiation debugging is on
  Multilink events debugging is on
VTEMPLATE:
  Virtual Template debugging is on
clearlake-lan-01#ping ip   
Target IP address: 172.21.104.254
Repeat count [5]: 20
Datagram size [100]: 1200
Timeout in seconds [2]: 
Extended commands [n]: 
Sweep range of sizes [n]: 
Type escape sequence to abort.
Sending 20, 1200-byte ICMP Echos to 172.21.104.254, timeout is 2 seconds:

Jul 25 13:20:29.047 UTC: As34 DDR: rotor dialout [priority]
Jul 25 13:20:29.047 UTC: As34 DDR: Dialing cause ip (s=172.21.125.1, 
d=172.21.104.254)

!--- Dialing Reason

Jul 25 13:20:29.047 UTC: As34 DDR: Attempting to dial 
      
      
        5551212 
      

!--- Number being dialed

Jul 25 13:20:29.047 UTC: CHAT34: Attempting async line dialer script
Jul 25 13:20:29.047 UTC: CHAT34: Dialing using Modem script: 
async-mppp & System script: none

!--- Using chat script async-mppp for dialout

Jul 25 13:20:29.051 UTC: CHAT34: process started
Jul 25 13:20:29.051 UTC: CHAT34: Asserting DTR
Jul 25 13:20:29.051 UTC: CHAT34: Chat script async-mppp started

!--- Call is being established; !--- note the time elapsed for call setup

Jul 25 13:20:54.831 UTC: CHAT34: Chat script async-mppp finished, 
status = Success.
Jul 25 13:20:56.831 UTC: 
%LINK-3-UPDOWN: Interface Async34, changed state to up
Jul 25 13:20:56.831 UTC: 
Async34 DDR: Dialer statechange to up
Jul 25 13:20:56.831 UTC: 
%DIALER-6-BIND: Interface As34 bound to profile Di1
Jul 25 13:20:56.831 UTC: 
Async34 DDR: Dialer call has been placed

!--- PPP negotiation begins

Jul 25 13:20:56.831 UTC: As34 PPP: Treating connection as a callout
Jul 25 13:20:56.831 UTC: As34 PPP: Phase is ESTABLISHING, Active Open
Jul 25 13:20:56.831 UTC: As34 PPP: No remote authentication for call-out

!--- CHAP challenge is configured for callin only !--- LCP negotiation begins; Multilink parameters are also negotiated

Jul 25 13:20:56.835 UTC: As34 LCP: O CONFREQ [Closed] id 43 len 43
Jul 25 13:20:56.835 UTC: As34 LCP:    ACCM 0x000A0000 (0x0206000A0000)
Jul 25 13:20:56.835 UTC: As34 LCP:    MagicNumber 0x4395638E (0x05064395638E)
Jul 25 13:20:56.835 UTC: As34 LCP:    PFC (0x0702)
Jul 25 13:20:56.835 UTC: As34 LCP:    ACFC (0x0802)
Jul 25 13:20:56.835 UTC: As34 LCP:    MRRU 1524 (0x110405F4)

!--- Negotiate Maximum Receive Reconstructed Unit (MRRU) !--- MRRU is the maximum packet size this end will reconstruct

Jul 25 13:20:56.835 UTC: As34 LCP:    EndpointDisc 1 Local
Jul 25 13:20:56.835 UTC: As34 LCP:     (0x131301636C6561726C616B652D6C616E)
Jul 25 13:20:56.835 UTC: As34 LCP:     (0x2D3031).
Jul 25 13:20:58.831 UTC: As34 LCP: TIMEout: State REQsent
Jul 25 13:20:58.831 UTC: As34 LCP: O CONFREQ [REQsent] id 44 Len 43
Jul 25 13:20:58.831 UTC: As34 LCP:    ACCM 0x000A0000 (0x0206000A0000)
Jul 25 13:20:58.831 UTC: As34 LCP:    MagicNumber 0x4395638E (0x05064395638E)
Jul 25 13:20:58.831 UTC: As34 LCP:    PFC (0x0702)
Jul 25 13:20:58.831 UTC: As34 LCP:    ACFC (0x0802)
Jul 25 13:20:58.831 UTC: As34 LCP:    MRRU 1524 (0x110405F4)
Jul 25 13:20:58.831 UTC: As34 LCP:    EndpointDisc 1 Local
Jul 25 13:20:58.831 UTC: As34 LCP:     (0x131301636C6561726C616B652D6C616E)
Jul 25 13:20:58.831 UTC: As34 LCP:     (0x2D3031).
Jul 25 13:21:00.831 UTC: As34 LCP: TIMEout: State REQsent
Jul 25 13:21:00.831 UTC: As34 LCP: O CONFREQ [REQsent] id 45 Len 43
Jul 25 13:21:00.831 UTC: As34 LCP:    ACCM 0x000A0000 (0x0206000A0000)
Jul 25 13:21:00.831 UTC: As34 LCP:    MagicNumber 0x4395638E (0x05064395638E)
Jul 25 13:21:00.831 UTC: As34 LCP:    PFC (0x0702)
Jul 25 13:21:00.831 UTC: As34 LCP:    ACFC (0x0802)
Jul 25 13:21:00.831 UTC: As34 LCP:    MRRU 1524 (0x110405F4)
Jul 25 13:21:00.831 UTC: As34 LCP:    EndpointDisc 1 Local
Jul 25 13:21:00.831 UTC: As34 LCP:     (0x131301636C6561726C616B652D6C616E)
Jul 25 13:21:00.831 UTC: As34 LCP:     (0x2D3031)
Jul 25 13:21:01.135 UTC: As34 LCP: I CONFACK [REQsent] id 45 Len 43
Jul 25 13:21:01.135 UTC: As34 LCP:    ACCM 0x000A0000 (0x0206000A0000)
Jul 25 13:21:01.135 UTC: As34 LCP:    MagicNumber 0x4395638E (0x05064395638E)
Jul 25 13:21:01.135 UTC: As34 LCP:    PFC (0x0702)
Jul 25 13:21:01.135 UTC: As34 LCP:    ACFC (0x0802)
Jul 25 13:21:01.135 UTC: As34 LCP:    MRRU 1524 (0x110405F4)
Jul 25 13:21:01.135 UTC: As34 LCP:    EndpointDisc 1 Local
Jul 25 13:21:01.135 UTC: As34 LCP:     (0x131301636C6561726C616B652D6C616E)
Jul 25 13:21:01.135 UTC: As34 LCP:     (0x2D3031)
Jul 25 13:21:01.139 UTC: As34 LCP: I CONFREQ [ACKrcvd] id 6 Len 47
Jul 25 13:21:01.139 UTC: As34 LCP:    ACCM 0x000A0000 (0x0206000A0000)
Jul 25 13:21:01.143 UTC: As34 LCP:    AuthProto CHAP (0x0305C22305)
Jul 25 13:21:01.143 UTC: As34 LCP:    MagicNumber 0xE16DFC8D (0x0506E16DFC8D)
Jul 25 13:21:01.143 UTC: As34 LCP:    PFC (0x0702)
Jul 25 13:21:01.143 UTC: As34 LCP:    ACFC (0x0802)
Jul 25 13:21:01.143 UTC: As34 LCP:    MRRU 1524 (0x110405F4)
Jul 25 13:21:01.143 UTC: As34 LCP:    EndpointDisc 1 Local
Jul 25 13:21:01.143 UTC: As34 LCP:     (0x131201626F62736C616B652D6E61732D)
Jul 25 13:21:01.143 UTC: As34 LCP:     (0x3031)
Jul 25 13:21:01.143 UTC: As34 LCP: O CONFACK [ACKrcvd] id 6 Len 47
Jul 25 13:21:01.143 UTC: As34 LCP:    ACCM 0x000A0000 (0x0206000A0000)
Jul 25 13:21:01.143 UTC: As34 LCP:    AuthProto CHAP (0x0305C22305)
Jul 25 13:21:01.143 UTC: As34 LCP:    MagicNumber 0xE16DFC8D (0x0506E16DFC8D)
Jul 25 13:21:01.143 UTC: As34 LCP:    PFC (0x0702)
Jul 25 13:21:01.143 UTC: As34 LCP:    ACFC (0x0802)
Jul 25 13:21:01.143 UTC: As34 LCP:    MRRU 1524 (0x110405F4)
Jul 25 13:21:01.143 UTC: As34 LCP:    EndpointDisc 1 Local
Jul 25 13:21:01.143 UTC: As34 LCP:     (0x131201626F62736C616B652D6E61732D)
Jul 25 13:21:01.143 UTC: As34 LCP:     (0x3031)

!--- Both sides have CONFACKed the parameters !--- MRRU of 1524 bytes and the Endpoint Discriminator have been negotiated

Jul 25 13:21:01.143 UTC: As34 LCP: State is Open

!--- LCP negotiation complete

Jul 25 13:21:01.147 UTC: As34 PPP: Phase is AUTHENTICATING, by the peer

!--- Received a challenge from the remote router

Jul 25 13:21:01.351 UTC: As34 CHAP: I CHALLENGE id 3 Len 36 
from "bobslake-nas-01"
Jul 25 13:21:01.351 UTC: As34 CHAP: O RESPONSE id 3 Len 
Jul 25 13:21:01.539 UTC: As34 CHAP: I SUCCESS id 3 Len 4

!--- CHAP authentication successful

Jul 25 13:21:01.539 UTC: As34 PPP: Phase is VIRTUALIZED

!--- Virtualize Async 34 !--- Virtual Access interface will represent the MP bundle

Jul 25 13:21:01.543 UTC: Vi1 VTEMPLATE: Reuse Vi1, recycle queue size 0
Jul 25 13:21:01.543 UTC: Vi1 VTEMPLATE: Hardware address 0030.9401.f101
Jul 25 13:21:01.543 UTC: Vi1 PPP: Phase is DOWN, Setup
Jul 25 13:21:01.543 UTC: %DIALER-6-BIND: Interface Vi1 bound to profile Di1
Jul 25 13:21:01.543 UTC: Vi1 VTEMPLATE: Has a new cloneblk dialer, 
now it has dialer
Jul 25 13:21:01.547 UTC: %LINK-3-UPDOWN: Interface Virtual-Access1, 
changed state to up
Jul 25 13:21:01.547 UTC: Virtual-Access1 DDR: Dialer statechange to up

!--- Virtual Access Interface is up !--- Negotiate LCP and PPP parameters for Virtual-Access Interface

Jul 25 13:21:01.547 UTC: Virtual-Access1 DDR: Dialer call has been placed
Jul 25 13:21:01.547 UTC: Vi1 PPP: Treating connection as a callout
Jul 25 13:21:01.547 UTC: Vi1 PPP: Phase is ESTABLISHING, Active Open
Jul 25 13:21:01.547 UTC: Vi1 PPP: No remote authentication for call-out
Jul 25 13:21:01.547 UTC: Vi1 LCP: O CONFREQ [Closed] id 1 Len 33
Jul 25 13:21:01.547 UTC: Vi1 LCP:    MagicNumber 0x439575FC (0x0506439575FC)
Jul 25 13:21:01.547 UTC: Vi1 LCP:    MRRU 1524 (0x110405F4)
Jul 25 13:21:01.551 UTC: Vi1 LCP:    EndpointDisc 1 Local
Jul 25 13:21:01.551 UTC: Vi1 LCP:     (0x131301636C6561726C616B652D6C616E)
Jul 25 13:21:01.551 UTC: Vi1 LCP:     (0x2D3031)
Jul 25 13:21:01.551 UTC: Vi1 PPP: Phase is UP
Jul 25 13:21:01.551 UTC: Vi1 IPCP: O CONFREQ [Closed] id 1 Len 10
Jul 25 13:21:01.551 UTC: Vi1 IPCP:    Address 0.0.0.0 (0x030600000000)
Jul 25 13:21:01.551 UTC: 
As34 MLP: bobslake-nas-01, multilink up, first link

!--- First multilink connection is virtualized

Jul 25 13:21:01.651 UTC: Vi1 IPCP: I CONFREQ [REQsent] id 1 Len 10
Jul 25 13:21:01.651 UTC: Vi1 IPCP:    Address 172.21.104.254 (0x0306AC1568FE)
Jul 25 13:21:01.651 UTC: Vi1 IPCP: O CONFACK [REQsent] id 1 Len 10
Jul 25 13:21:01.651 UTC: Vi1 IPCP:    Address 172.21.104.254 (0x0306AC1568FE)
Jul 25 13:21:01.731 UTC: Vi1 IPCP: I CONFNAK [ACKsent] id 1 Len 10
Jul 25 13:21:01.731 UTC: Vi1 IPCP:    Address 172.21.104.48 (0x0306AC156830)
Jul 25 13:21:01.731 UTC: Vi1 IPCP: O CONFREQ [ACKsent] id 2 Len 10
Jul 25 13:21:01.731 UTC: Vi1 IPCP:    Address 172.21.104.48 (0x0306AC156830)
Jul 25 13:21:01.915 UTC: Vi1 IPCP: I CONFACK [ACKsent] id 2 Len 10
Jul 25 13:21:01.915 UTC: Vi1 IPCP:    Address 172.21.104.48 (0x0306AC156830)
Jul 25 13:21:01.915 UTC: Vi1 IPCP: State is Open
Jul 25 13:21:01.915 UTC: Di1 IPCP: Install negotiated IP interface 
address 172.21.104.48

!--- IP address is assigned to virtual-access interface

Jul 25 13:21:01.919 UTC: Vi1 DDR: dialer protocol up
Jul 25 13:21:01.919 UTC: Di1 IPCP: Install route to 172.21.104.254

!--- Route to loopback address of remote router

Jul 25 13:21:02.539 UTC: 
%LINEPROTO-5-UPDOWN: Line protocol on Interface Async34, 
changed state to up
Jul 25 13:21:02.551 UTC: 
%LINEPROTO-5-UPDOWN: Line protocol on Interface 
Virtual-Access1, changed state to up

!--- Full connectivity with first async connection !--- Begin dialout using second async interface

Jul 25 13:21:08.191 UTC: As33 DDR: rotor dialout [priority]
Jul 25 13:21:08.191 UTC: 
As33 DDR: Attempting to dial 
      
      
        5551212 
      

!--- Number to be dialed; this number is the PRI on the remote router

Jul 25 13:21:08.191 UTC: CHAT33: Attempting async line dialer script
Jul 25 13:21:08.191 UTC: CHAT33: Dialing using Modem script: 
async-mppp & System script: none

!--- Use chat script async-mppp for dialout

Jul 25 13:21:08.191 UTC: CHAT33: process started
Jul 25 13:21:08.191 UTC: CHAT33: Asserting DTR
Jul 25 13:21:08.191 UTC: CHAT33: Chat script async-mppp started
Jul 25 13:21:33.859 UTC: CHAT33: Chat script async-mppp finished, 
status = Success

!--- Chat script successful

Jul 25 13:21:35.859 UTC: %LINK-3-UPDOWN: Interface Async33, 
changed state to up
Jul 25 13:21:35.859 UTC: Async33 DDR: Dialer statechange to up
Jul 25 13:21:35.859 UTC: %DIALER-6-BIND: Interface As33 bound to 
profile Di1
Jul 25 13:21:35.859 UTC: Async33 DDR: Dialer call has been placed

!--- PPP negotiation begins

Jul 25 13:21:35.859 UTC: As33 PPP: Treating connection as a callout
Jul 25 13:21:35.859 UTC: As33 PPP: Phase is ESTABLISHING, Active Open
Jul 25 13:21:35.859 UTC: As33 PPP: No remote authentication for call-out

!--- CHAP challenge is configured for callin only !--- LCP negotiation begins; Multilink parameters are also negotiated

Jul 25 13:21:35.863 UTC: As33 LCP: O CONFREQ [Closed] id 21 Len 43
Jul 25 13:21:35.863 UTC: As33 LCP:    ACCM 0x000A0000 (0x0206000A0000)
Jul 25 13:21:35.863 UTC: As33 LCP:    MagicNumber 0x4395FC05(0x05064395FC05)
Jul 25 13:21:35.863 UTC: As33 LCP:    PFC (0x0702)
Jul 25 13:21:35.863 UTC: As33 LCP:    ACFC (0x0802)
Jul 25 13:21:35.863 UTC: As33 LCP:    MRRU 1524 (0x110405F4)

!--- negotiate Maximum Receive Reconstructed Unit (MRRU)

Jul 25 13:21:35.863 UTC: As33 LCP:    EndpointDisc 1 Local
Jul 25 13:21:35.863 UTC: As33 LCP:     (0x131301636C6561726C616B652D6C616E)
Jul 25 13:21:35.863 UTC: As33 LCP:     (0x2D3031)
Jul 25 13:21:37.859 UTC: As33 LCP: TIMEout: State REQsent
Jul 25 13:21:37.859 UTC: As33 LCP: O CONFREQ [REQsent] id 22 Len 43
Jul 25 13:21:37.859 UTC: As33 LCP:    ACCM 0x000A0000 (0x0206000A0000)
Jul 25 13:21:37.859 UTC: As33 LCP:    MagicNumber 0x4395FC05 (0x05064395FC05)
Jul 25 13:21:37.859 UTC: As33 LCP:    PFC (0x0702)
Jul 25 13:21:37.859 UTC: As33 LCP:    ACFC (0x0802)
Jul 25 13:21:37.859 UTC: As33 LCP:    MRRU 1524 (0x110405F4)
Jul 25 13:21:37.859 UTC: As33 LCP:    EndpointDisc 1 Local
Jul 25 13:21:37.859 UTC: As33 LCP:     (0x131301636C6561726C616B652D6C616E)
Jul 25 13:21:37.859 UTC: As33 LCP:     (0x2D3031)
Jul 25 13:21:39.859 UTC: As33 LCP: TIMEout: State REQsent
Jul 25 13:21:39.859 UTC: As33 LCP: O CONFREQ [REQsent] id 23 Len 43
Jul 25 13:21:39.859 UTC: As33 LCP:    ACCM 0x000A0000 (0x0206000A0000)
Jul 25 13:21:39.859 UTC: As33 LCP:    MagicNumber 0x4395FC05 (0x05064395FC05)
Jul 25 13:21:39.859 UTC: As33 LCP:    PFC (0x0702)
Jul 25 13:21:39.859 UTC: As33 LCP:    ACFC (0x0802)
Jul 25 13:21:39.859 UTC: As33 LCP:    MRRU 1524 (0x110405F4)
Jul 25 13:21:39.859 UTC: As33 LCP:    EndpointDisc 1 Local
Jul 25 13:21:39.859 UTC: As33 LCP:     (0x131301636C6561726C616B652D6C616E)
Jul 25 13:21:39.859 UTC: As33 LCP:     (0x2D3031)
Jul 25 13:21:40.199 UTC: As33 LCP: I CONFREQ [REQsent] id 6 Len 47
Jul 25 13:21:40.199 UTC: As33 LCP:    ACCM 0x000A0000 (0x0206000A0000)
Jul 25 13:21:40.203 UTC: As33 LCP:    AuthProto CHAP (0x0305C22305)
Jul 25 13:21:40.203 UTC: As33 LCP:    MagicNumber 0xE16E950F (0x0506E16E950F)
Jul 25 13:21:40.203 UTC: As33 LCP:    PFC (0x0702)
Jul 25 13:21:40.203 UTC: As33 LCP:    ACFC (0x0802)
Jul 25 13:21:40.203 UTC: As33 LCP:    MRRU 1524 (0x110405F4)
Jul 25 13:21:40.203 UTC: As33 LCP:    EndpointDisc 1 Local
Jul 25 13:21:40.203 UTC: As33 LCP:     (0x131201626F62736C616B652D6E61732D)
Jul 25 13:21:40.203 UTC: As33 LCP:     (0x3031)
Jul 25 13:21:40.203 UTC: As33 LCP: O CONFACK [REQsent] id 6 Len 47

!--- PPP parameters are agreed on (CONFACKed) by both sides

Jul 25 13:21:40.203 UTC: As33 LCP:    ACCM 0x000A0000 (0x0206000A0000)
Jul 25 13:21:40.203 UTC: As33 LCP:    AuthProto CHAP (0x0305C22305)
Jul 25 13:21:40.203 UTC: As33 LCP:    MagicNumber 0xE16E950F (0x0506E16E950F)
Jul 25 13:21:40.203 UTC: As33 LCP:    PFC (0x0702)
Jul 25 13:21:40.203 UTC: As33 LCP:    ACFC (0x0802)
Jul 25 13:21:40.203 UTC: As33 LCP:    MRRU 1524 (0x110405F4)

!--- MRRU of 1524 bytes is accepted

Jul 25 13:21:40.203 UTC: As33 LCP:    EndpointDisc 1 Local
Jul 25 13:21:40.203 UTC: As33 LCP:     (0x131201626F62736C616B652D6E61732D)
Jul 25 13:21:40.203 UTC: As33 LCP:     (0x3031)
Jul 25 13:21:40.207 UTC: As33 LCP: I CONFACK [ACKsent] id 23 Len 43
!--- PPP parameters are agreed on (CONFACKed) by both sides
Jul 25 13:21:40.207 UTC: As33 LCP:    ACCM 0x000A0000 (0x0206000A0000)
Jul 25 13:21:40.207 UTC: As33 LCP:    MagicNumber 0x4395FC05 (0x05064395FC05)
Jul 25 13:21:40.207 UTC: As33 LCP:    PFC (0x0702)
Jul 25 13:21:40.207 UTC: As33 LCP:    ACFC (0x0802)
Jul 25 13:21:40.207 UTC: As33 LCP:    MRRU 1524 (0x110405F4)

!--- MRRU of 1524 bytes is accepted

Jul 25 13:21:40.207 UTC: As33 LCP:    EndpointDisc 1 Local
Jul 25 13:21:40.207 UTC: As33 LCP:     (0x131301636C6561726C616B652D6C616E)
Jul 25 13:21:40.207 UTC: As33 LCP:     (0x2D3031)

!--- LCP negotiation is complete

Jul 25 13:21:40.207 UTC: As33 LCP: State is Open
Jul 25 13:21:40.207 UTC: As33 PPP: Phase is AUTHENTICATING, by the peer

!--- CHAP authentication begins

Jul 25 13:21:40.419 UTC: As33 CHAP: I CHALLENGE id 3 Len 36 
from "bobslake-nas-01"

!--- Received challenge from bobslake-nas-01

Jul 25 13:21:40.423 UTC: As33 CHAP: O RESPONSE id 3 Len 37 
from "clearlake-lan-01"
Jul 25 13:21:42.528 UTC: As33 CHAP: I SUCCESS id 3 Len 4

!--- CHAP authentication is successful

Jul 25 13:21:42.528 UTC: As33 PPP: Phase is VIRTUALIZED

!--- Async 33 is added to Virtualized MP bundle

Jul 25 13:21:42.528 UTC: As33 MLP: bobslake-nas-01, multilink up

!--- Multilink connection is up

Jul 25 13:21:43.528 UTC: %LINEPROTO-5-UPDOWN: 
Line protocol on Interface Async33, 
changed state to up
clearlake-lan-01#
Jul 25 13:23:52.028 UTC: Vi1 MLP: Disabling particle-fastswitching 
in 'bobslake-nas-01'
Jul 25 13:23:52.028 UTC: Vi1 MLP: Enabling particle-fastswitching 
on 'bobslake-nas-01'

!--- Cisco IOS adjusting fast switching strategy to keep in step !--- with delivery of packet fragments

Jul 25 13:23:53.872 UTC: Vi1 MLP: Disabling particle-fastswitching 
in 'bobslake-nas-01'
Jul 25 13:23:53.884 UTC: Vi1 MLP: Enabling particle-fastswitching 
on 'bobslake-nas-01'

Informazioni correlate

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• Multilink PPP su due interfacce asincrone seriali a livello fisico
• Configurazione del server NAS per Basic Dial Access
• Visualizzazione delle statistiche del chiamante
• Configurazione delle interfacce dei modelli virtuali
• Funzioni PPP di accesso virtuale in Cisco IOS
• Pagine di supporto PPP
• Supporto tecnico – Cisco Systems