Risoluzione dei problemi relativi alle adiacenze IS-IS
Introduzione
In questo documento viene descritto come risolvere i problemi relativi al protocollo IS-IS per le piattaforme Cisco IOS® XE.
Prerequisiti
Requisiti
Cisco raccomanda la conoscenza dei seguenti argomenti:
- Intermediate System to Intermediate System (IS-IS)
- Cisco IOS XE
Per ulteriori informazioni su questi argomenti, vedere:
Componenti usati
Il riferimento delle informazioni contenute in questo documento è il software Cisco IOS XE.
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.
Adiacenza IS-IS in basso
Questa sezione fornisce una soluzione al problema comune di IS-IS inattivo. Questo diagramma di rete è utilizzato come esempio:
Topologia di base
IS-IS non è attivo tra DeviceA e DeviceB.
DeviceA#show isis neighbors detail System Id Type Interface IP Address State Holdtime Circuit Id DeviceA#
DeviceB#show isis neighbors detail System Id Type Interface IP Address State Holdtime Circuit Id DeviceA L1L2 Twe1/0/9 192.0.2.1 DOWN 28 05 Area Address(es): 49.0001 SNPA: a84f.b1c3.9484 State Changed: never Format: Phase V Remote TID: 0 Local TID: 0 Interface name: TwentyFiveGigE1/0/9 Neighbor Circuit Id: 5 Adj sync: Full
Diagnosticare il problema:
1. Verificare la connettività tra i dispositivi.
DeviceA#ping 192.0.2.2 size 1500 df-bit Type escape sequence to abort. Sending 5, 1500-byte ICMP Echos to 192.0.2.2, timeout is 2 seconds: Packet sent with the DF bit set !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms DeviceA#
DeviceB#ping 192.0.2.1 size 1500 df-bit Type escape sequence to abort. Sending 5, 1500-byte ICMP Echos to 192.0.2.1, timeout is 2 seconds: Packet sent with the DF bit set !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms DeviceB#
2. Esaminare la configurazione su entrambi i lati.
DeviceA#show running-config | sec router isis ip router isis router isis net 49.0001.0000.0000.000a.00 DeviceA#
DeviceB#show running-config | sec router isis ip router isis router isis net 49.0001.0000.0000.000b.00 DeviceB#
3. Convalida se l'adiacenza è attiva al CLNS (Connectionless Network Service). In questo modo viene fornito un riepilogo dei router adiacenti connessi al dispositivo.
DeviceA#show clns neighbors detail System Id Interface SNPA State Holdtime Type Protocol 0000.0000.000B Te0/0/4 6c31.0edb.3b5f Up 257 IS ES-IS Area Address(es): 49.0001 Uptime: 02:02:11 Interface name: TenGigabitEthernet0/0/4 DeviceA#
DeviceB#show clns neighbors detail System Id Interface SNPA State Holdtime Type Protocol 0000.0000.000A Twe1/0/9 a84f.b1c3.9484 Down 20 L1L2 IS-IS Area Address(es): 49.0001 IP Address(es): 192.0.2.1* Uptime: 02:02:09 NSF capable Interface name: TwentyFiveGigE1/0/9 DeviceB#
Gli indirizzi MAC elencati in ciascun router adiacente CLNS sono gli indirizzi MAC dei dispositivi remoti che eseguono il peer con il dispositivo locale.
DeviceA#show interface TenGigabitEthernet0/0/4
TenGigabitEthernet0/0/4 is up, line protocol is up
Hardware is 8xSFP+, address is a84f.b1c3.9484 (bia a84f.b1c3.9484) < mac address appeared on SNPA DeviceB
Internet address is 192.0.2.1/30
MTU 1500 bytes, BW 10000000 Kbit/sec, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
DeviceB#show interface TwentyFiveGigE1/0/9
TwentyFiveGigE1/0/9 is up, line protocol is up (connected)
Hardware is Twenty Five Gigabit Ethernet, address is 6c31.0edb.3b5f (bia 6c31.0edb.3b5f) < mac address appeared on SNPA DeviceA
Internet address is 192.0.2.2/30
MTU 9216 bytes, BW 10000000 Kbit/sec, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
4. Eseguire il comando show clns interface
per verificare se i parametri corrispondono al peer.
Assicurarsi che corrispondano a questi valori:
- MTU (Maximum Transmission Unit)
- Tipo di circuito
| Periferica A |
DeviceA#show clns interface TenGigabitEthernet0/0/4 |
| Periferica B |
DeviceB#show clns interface TwentyFiveGigE1/0/9 |
In questo scenario, il problema è correlato alla mancata corrispondenza dell'MTU. Se il peer remoto non è accessibile, debug isis adj-packets
può visualizzare il valore MTU inviato e ricevuto.
Nota: questa condizione si applica solo quando il comando show clns interfacestampe if state INIT.
DeviceA#debug isis adj-packets TenGigabitEthernet 0/0/4
IS-IS Adjacency related packets debugging is on for router process null
*Jul 18 23:24:16.598: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5
*Jul 18 23:24:16.599: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496 < MTU sent to the neighbor >
*Jul 18 23:24:25.189: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5
*Jul 18 23:24:25.189: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496
*Jul 18 23:24:34.057: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5
*Jul 18 23:24:34.057: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496
*Jul 18 23:24:42.866: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5
*Jul 18 23:24:42.866: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496
*Jul 18 23:24:51.646: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5
*Jul 18 23:24:51.646: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496
*Jul 18 23:24:59.606: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5
*Jul 18 23:24:59.606: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496
DeviceB#debug isis adj-packets twentyFiveGigE 1/0/9
*Jul 18 23:53:22.420: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:INIT, length 9212 < MTU sent to the neighbor >
*Jul 18 23:53:22.591: ISIS-Adj: Rec serial IIH from a84f.b1c3.9484 (TwentyFiveGigE1/0/9)
*Jul 18 23:53:22.591: ISIS-Adj: cir type L1L2, cir id 05, length 1496 < MTU received from neighbor >
*Jul 18 23:53:22.592: ISIS-Adj: rcvd state DOWN, old state INIT, new state INIT, nbr usable TRUE
*Jul 18 23:53:22.592: ISIS-Adj: RCV:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x49000184 Length:5
*Jul 18 23:53:22.592: ISIS-Adj: Nghbr Ckt ID changed: FALSE
*Jul 18 23:53:22.592: ISIS-Adj: newstate:1, state_changed:0, going_up:0, going_down:0
*Jul 18 23:53:22.592: ISIS-Adj: Action = ACCEPT
*Jul 18 23:53:22.592: ISIS-Adj: ACTION_ACCEPT:
...
Adiacenza ISIS inattiva (non correlata a MTU non corrispondente)
IS-IS non è attivo e l'MTU corrisponde sulle interfacce.
DeviceA#show clns neighbors System Id Interface SNPA State Holdtime Type Protocol DeviceA#
DeviceB#show clns neighbors System Id Interface SNPA State Holdtime Type Protocol DeviceB#
- Convalidare la configurazione corrispondente al peer.
- Assicurarsi che l'interfaccia fisica sia in buone condizioni per la trasmissione (nessun errore o problema di livelli di luce).
- Verificare la connettività tra peer (test ping, aggiunta delle dimensioni MTU e del bit DF).
- Convalidare i vicini CLNS tra i peer.
- Verificare che entrambe le estremità abbiano la stessa MTU e lo stesso tipo di circuito insieme allo stato.
| Periferica A |
DeviceA#show clns interface TenGigabitEthernet 0/0/4 |
| Periferica B |
DeviceB#show clns interface twentyFiveGigE 1/0/9 |
6. Abilita debug isis adj-packet
e convalidare i pacchetti inviati e ricevuti.
DeviceA#debug isis adj-packets TenGigabitEthernet 0/0/4
IS-IS Adjacency related packets debugging is on for router process null *Jul 19 13:32:52.788: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5 *Jul 19 13:32:52.788: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496 *Jul 19 13:33:00.708: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5 *Jul 19 13:33:00.709: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496 *Jul 19 13:33:09.726: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5 *Jul 19 13:33:09.726: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496 *Jul 19 13:33:18.376: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5 *Jul 19 13:33:18.376: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496 *Jul 19 13:33:26.132: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5 *Jul 19 13:33:26.132: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496 DeviceA#
DeviceB#debug isis adj-packets TwentyFiveGigE1/0/9 IS-IS Adjacency related packets debugging is on for router process null *Jul 19 14:01:32.125: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x0 Length:5 *Jul 19 14:01:32.125: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:DOWN, length 1496 *Jul 19 14:01:40.005: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x0 Length:5 *Jul 19 14:01:40.005: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:DOWN, length 1496 *Jul 19 14:01:49.602: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x0 Length:5 *Jul 19 14:01:49.602: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:DOWN, length 1496 *Jul 19 14:01:58.284: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x0 Length:5 *Jul 19 14:01:58.284: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:DOWN, length 1496
Entrambi i dispositivi stanno inviando, ma non ricevono il pacchetto Hello dai vicini.
7. Abilitare un'acquisizione per verificare che i pacchetti vengano inviati a ciascun router adiacente. Una volta completata la cattura, esportarla su bootflash o flash come.pcap file
DeviceA#show monitor cap cap parameter
monitor capture cap interface TenGigabitEthernet0/0/4 BOTH < Interface from where send and receive the Hello Packets >
monitor capture cap control-plane IN < Packets to be process and generated by the CPU >
monitor capture cap access-list TAC < ACL for capture only the IS-IS packets >
monitor capture cap buffer size 10
monitor capture cap limit pps 1000
DeviceA#show access-list TAC
Extended MAC access list TAC
permit host a84f.b1c3.9484 host 0900.2b00.0005 < Local MAC address towards the IS-IS Hello >
permit host 6c31.0edb.3b5f host 0900.2b00.0005 < Remote MAC address towards the IS-IS Hello >
DeviceB#show monitor capture cap parameter monitor capture cap interface TwentyFiveGigE1/0/9 BOTH < Interface from where send and receive the Hello Packets > monitor capture cap control-plane BOTH < Packets to be process and generated by the CPU > monitor capture cap match any < match all the packets on the switch > monitor capture cap buffer size 10
Nota: l'EPC sugli switch Catalyst Cisco IOS XE acquisisce solo gli helper IS-IS in uscita e non i pacchetti in entrata. In alternativa, si consigliano le acquisizioni SPAN.
In questa tabella è riportato un riferimento ai pacchetti Hello.
| Nome | Indirizzo Mac di destinazione |
| Tutti gli IS L1 | 0180.c200.0014 |
| Tutti gli IS L2 | 0180.c200.0015 |
| Tutti gli IS | 0900.2b00.0005 |
| Tutti gli ES | 0900.2b00.0004 |
8. Esaminare la cattura esportata e assicurarsi che i pacchetti hello vengano scambiati tra vicini.
La periferica A invia i pacchetti hello aggiungendo il proprio ID di sistema (quadratino rosso). È previsto che riceva un pacchetto dal router adiacente con il relativo ID di sistema. In questa acquisizione, è possibile notare che DeviceB non inoltra questi pacchetti al peer.
ISIS Down Capture DeviceA
L'acquisizione DeviceB mostra che i pacchetti hello vengono inviati al router adiacente (quadrato rosso). Tuttavia, analogamente all'ultima acquisizione, non riceve i pacchetti Hello dal router adiacente.
Acquisizione ISIS DeviceB inattiva
Il problema in questo scenario è dovuto a un dispositivo intermedio che non consente l'invio dei pacchetti hello. Se si verifica una situazione simile e si desidera risolvere ulteriormente il problema, aprire una richiesta Cisco TAC.
Adiacenza IS-IS instabile
In questa sezione viene fornita una soluzione al problema comune dei flap IS-IS.
Diagnosticare il problema:
IS-IS è instabile tra DeviceA e DeviceB.
DeviceA#show logging
Jul 19 15:05:03.623: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Down, hold time expired
Jul 19 15:05:15.075: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Up, new adjacency
Jul 19 15:07:04.575: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Down, hold time expired
Jul 19 15:07:15.759: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Up, new adjacency
Jul 19 15:09:04.983: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Down, hold time expired
Jul 19 15:09:14.835: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Up, new adjacency
DeviceB#show logging
Jul 19 15:05:02.316: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Down, hold time expired
Jul 19 15:05:18.191: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Up, new adjacency
Jul 19 15:07:09.280: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Down, hold time expired
Jul 19 15:07:18.876: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Up, new adjacency
Jul 19 15:09:06.080: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Down, hold time expired!
Jul 19 15:09:17.948: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Up, new adjacency
1. Verificare la connettività tra peer (test ping con dimensioni MTU e bit DF impostati).
2. Assicurarsi che l'interfaccia fisica sia in buone condizioni per la trasmissione (nessun errore o problema di livelli di luce).
3. Convalidare i router adiacenti CLNS per l'invio di traffico tra loro con il comando show clns traffic interface
.
DeviceA#show clns traffic interface TenGigabitEthernet0/0/4 CLNS: Time since last clear: 00:01:57 CLNS & ESIS Output: 3, Input: 21 Dropped Protocol not enabled on interface: 0 CLNS Local: 0, Forward: 0
Interface TenGigabitEthernet0/0/4: IS-IS: Time since last clear: 00:01:57 IS-IS: Level-1 Hellos (sent/rcvd): 0/0 IS-IS: Level-2 Hellos (sent/rcvd): 0/0 IS-IS: PTP Hellos (sent/rcvd): 15/11 < DeviceA sends hello packets and receives less than its sends> IS-IS: Level-1 LSPs flooded (sent/rcvd): 2/2 IS-IS: Level-2 LSPs flooded (sent/rcvd): 2/2 IS-IS: Level-1 CSNPs (sent/rcvd): 1/1 IS-IS: Level-2 CSNPs (sent/rcvd): 1/1 IS-IS: Level-1 PSNPs (sent/rcvd): 1/1 IS-IS: Level-2 PSNPs (sent/rcvd): 1/1 IS-IS: Level-1 DR Elections: 0 IS-IS: Level-2 DR Elections: 0
DeviceB#show clns traffic interface TwentyFiveGigE1/0/9
CLNS: Time since last clear: 00:00:27
CLNS queue depth: 0/100, drops: 0, highest: 2
CLNS & ESIS Output: 1, Input: 14
Dropped Protocol not enabled on interface: 0
CLNS Local: 0, Forward: 0
Suggerimento: il comando clns traffic visualizza l'elenco IS-IS Hellos in base al tipo di rete IS-IS Level e IS-IS.
4. Abilita debug ISIS adj-packets
per vedere quali pacchetti vengono scambiati tra i vicini.
DeviceA#show isis adj-packets TenGigabitEthernet0/0/4 < Hellos sent to the DeviceB with no response > Jul 19 18:58:34.779: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15 Jul 19 18:58:34.779: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496 Jul 19 18:58:42.719: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15 Jul 19 18:58:42.719: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496 Jul 19 18:58:50.430: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15 Jul 19 18:58:50.430: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496 Jul 19 18:58:58.356: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15 Jul 19 18:58:58.356: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496 < IS-IS declares the protocol down > Jul 19 18:59:01.879: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Down, hold time expired < IS-IS sends hellos to the neighbor and receives a response from DeviceB > Jul 19 18:59:01.879: ISIS-Adj: L2 adj count 0 Jul 19 18:59:07.724: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5 Jul 19 18:59:07.724: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496 Jul 19 18:59:15.894: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x0 Length:5 Jul 19 18:59:15.894: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:DOWN, length 1496 Jul 19 18:59:15.896: ISIS-Adj: Rec serial IIH from 6c31.0edb.3b5f (TenGigabitEthernet0/0/4) Jul 19 18:59:15.896: ISIS-Adj: cir type L2, cir id 0B, length 1496 Jul 19 18:59:15.896: ISIS-Adj: RCV:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15 Jul 19 18:59:15.896: ISIS-Adj: Nghbr Ckt ID changed: TRUE Jul 19 18:59:15.896: ISIS-Adj: received Neighbor System-ID (must be our) 0000.0000.000A Jul 19 18:59:15.896: ISIS-Adj: received Neighbor ext.circuit ID (must be our) 0x5 Jul 19 18:59:15.896: ISIS-Adj: newstate:1, state_changed:1, going_up:0, going_down:0 Jul 19 18:59:15.896: ISIS-Adj: Action = GOING UP, new type = L2 < DeviceA declares that the adjacency is UP and starts to establish the session > Jul 19 18:59:15.896: ISIS-Adj: New serial adjacency Jul 19 18:59:15.896: ISIS-Adj: rcvd state INIT, old state DOWN, new state INIT, nbr usable TRUE Jul 19 18:59:15.898: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15 Jul 19 18:59:15.898: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:INIT, length 1496 Jul 19 18:59:15.900: ISIS-Adj: Rec serial IIH from 6c31.0edb.3b5f (TenGigabitEthernet0/0/4) Jul 19 18:59:15.900: ISIS-Adj: cir type L2, cir id 0B, length 1496 Jul 19 18:59:15.900: ISIS-Adj: rcvd state UP, old state INIT, new state UP, nbr usable TRUE Jul 19 18:59:15.900: ISIS-Adj: RCV:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15 Jul 19 18:59:15.900: ISIS-Adj: Nghbr Ckt ID changed: FALSE Jul 19 18:59:15.900: ISIS-Adj: received Neighbor System-ID (must be our) 0000.0000.000A Jul 19 18:59:15.900: ISIS-Adj: received Neighbor ext.circuit ID (must be our) 0x5 Jul 19 18:59:15.900: ISIS-Adj: newstate:0, state_changed:1, going_up:1, going_down:0 Jul 19 18:59:15.900: ISIS-Adj: Action = GOING UP, new type = L2 Jul 19 18:59:15.900: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Up, new adjacency
DeviceB#debug isis adj-packets TwentyFiveGigE1/0/9 < Hello sent to the DeviceA with no response > Jul 19 18:58:44.105: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15 Jul 19 18:58:44.105: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:UP, length 1496 Jul 19 18:58:51.814: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15 Jul 19 18:58:51.814: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:UP, length 1496 Jul 19 18:58:59.768: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15 Jul 19 18:58:59.768: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:UP, length 1496 < IS-IS declares the protocol down > Jul 19 18:59:07.886: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Down, hold time expired
< IS-IS sends hellos to the neighbor and receives a response from DeviceA >
Jul 19 18:59:07.887: ISIS-Adj: L2 adj count 0 Jul 19 18:59:08.422: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x0 Length:5 Jul 19 18:59:08.422: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:DOWN, length 1496 Jul 19 18:59:16.144: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x0 Length:5 Jul 19 18:59:16.144: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:DOWN, length 1496 Jul 19 18:59:19.001: ISIS-Adj: Rec serial IIH from a84f.b1c3.9484 (TwentyFiveGigE1/0/9) Jul 19 18:59:19.001: ISIS-Adj: cir type L2, cir id 05, length 1496 Jul 19 18:59:19.001: ISIS-Adj: RCV:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0x49000184 Length:5 Jul 19 18:59:19.001: ISIS-Adj: Nghbr Ckt ID changed: TRUE Jul 19 18:59:19.001: ISIS-Adj: newstate:1, state_changed:1, going_up:0, going_down:0 Jul 19 18:59:19.001: ISIS-Adj: Action = GOING UP, new type = L2 < DeviceB declares that the adjacency is UP and starts to establish the session > Jul 19 18:59:19.001: ISIS-Adj: New serial adjacency Jul 19 18:59:19.001: ISIS-Adj: rcvd state DOWN, old state DOWN, new state INIT, nbr usable TRUE Jul 19 18:59:19.002: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15 Jul 19 18:59:19.002: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:INIT, length 1496 Jul 19 18:59:19.004: ISIS-Adj: Rec serial IIH from a84f.b1c3.9484 (TwentyFiveGigE1/0/9) Jul 19 18:59:19.004: ISIS-Adj: cir type L2, cir id 05, length 1496 Jul 19 18:59:19.004: ISIS-Adj: rcvd state INIT, old state INIT, new state UP, nbr usable TRUE Jul 19 18:59:19.004: ISIS-Adj: RCV:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15 Jul 19 18:59:19.004: ISIS-Adj: Nghbr Ckt ID changed: FALSE Jul 19 18:59:19.004: ISIS-Adj: received Neighbor System-ID (must be our) 0000.0000.000B Jul 19 18:59:19.004: ISIS-Adj: received Neighbor ext.circuit ID (must be our) 0xB Jul 19 18:59:19.004: ISIS-Adj: newstate:0, state_changed:1, going_up:1, going_down:0 Jul 19 18:59:19.004: ISIS-Adj: Action = GOING UP, new type = L2 Jul 19 18:59:19.004: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Up, new adjacency
5. Abilitare un'acquisizione per verificare che i pacchetti vengano inviati a ciascun router adiacente. Una volta completata la cattura, esportarla su bootflash come .pcap file e caricarlo su un server TFTP per ulteriori dettagli.
Il dispositivo A riceve un pacchetto dal dispositivo B (19:15.05) dopo aver ricevuto il pacchetto. Il dispositivo A invia il saluto corrispondente senza alcuna risposta dal vicino fino a quando non raggiunge il tempo di attesa scaduto, che per impostazione predefinita è 30 secondi (quadrato rosso).
In questo caso, il router dichiara l'adiacenza inattiva. Trascorso questo periodo, DeviceB invia il suo saluto e viene ricevuto da DeviceA e questi pacchetti vengono scambiati senza problemi (quadratino verde).
Dispositivo instabile ISISA
La cattura dalla periferica B è simile al sintomo dal peer. Il dispositivo non riceve i pacchetti hello dal router adiacente. L'ultimo pacchetto viene inviato dalla periferica B senza risposta dalla periferica A finché non raggiunge il timer di attesa di 30 secondi. Questo interruttore considera l'adiacenza in basso. Dopo questo errore, lo switch riceve il saluto da DeviceA e avvia il vicinato.
Dispositivo instabile ISISB
Alla fine si verifica un problema con il trasporto e occorre verificare il motivo per cui i pacchetti vengono persi.
Adiacenza IS-IS instabile (lampi casuali)
IS-IS è instabile tra DeviceA e DeviceB. Il protocollo incontra flap casuali.
DeviceA#show logging Jul 21 10:03:38.633: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Down, hold time expired Jul 21 10:05:10.272: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Up, new adjacency Jul 21 10:33:41.528: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Down, hold time expired Jul 21 10:35:07.979: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Up, new adjacency Jul 21 11:03:42.442: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Down, hold time expired Jul 21 11:05:08.469: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Up, new adjacency
DeviceB#show logging Jul 21 10:03:44.535: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Down, hold time expired Jul 21 10:05:13.281: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Up, new adjacency Jul 21 10:33:38.408: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Down, hold time expired Jul 21 10:35:10.989: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Up, new adjacency Jul 21 11:03:39.291: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Down, hold time expired Jul 21 11:05:11.479: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Up, new adjacency
Quando si verifica il problema, assicurarsi di procedere come segue:
- Verificare che la configurazione corrisponda al peer.
- Assicurarsi che l'interfaccia fisica sia in buone condizioni per la trasmissione (nessun errore o problema di livelli di luce).
- Verificare la connettività tra peer (eseguire il ping con le dimensioni MTU e il bit DF impostato).
Suggerimento: non è facile risolvere questi problemi a causa delle condizioni dei risvolti casuali. Per risolvere questa situazione, è consigliabile utilizzare script per eseguire i comandi necessari e continuare con la risoluzione dei problemi.
4. Procedere con la configurazione di un'acquisizione per il monitoraggio con un elenco degli accessi per essere più specifici nella risoluzione dei problemi.
5. Disabilitare la console di registrazione e abilitare debug isis adj-packets
.
DeviceA(config)#no logging console DeviceA(config)#exit DeviceA#debug isis adj-packets TenGigabitEthernet0/0/4
6. Abilitare l'acquisizione dei pacchetti sull'apparecchiatura e attivarla.
DeviceA#show monitor capture cap parameter
monitor capture cap interface TenGigabitEthernet0/0/4 BOTH monitor capture cap control-plane IN monitor capture cap access-list TAC > match only the packets allowed on the ACL monitor capture cap buffer size 100 circular > when the capture reaches the size of 100 MB this overwrite the previous information. monitor capture cap limit pps 1000
DeviceA#show access-lists TAC Extended MAC access list TAC permit host a84f.b1c3.9484 host 0900.2b00.0005 < Local MAC address towards the IS-IS Hello > permit host 6c31.0edb.3b5f host 0900.2b00.0005 < Remote MAC address towards the IS-IS Hello >
DeviceA#monitor capture cap start
7. Configurare Embedded Event Manager (EEM) sul dispositivo Cisco. Una volta attivato il modello syslog, il problema genera log che vengono memorizzati nella memoria flash come .txt file. Per ulteriori informazioni, caricarle su un server TFTP.
DeviceA#show running-config | sec event event manager applet ISIS_Flap authorization bypass
event syslog pattern "%CLNS-5-ADJCHANGE:.*hold time expired"
action 1.0 syslog msg "ISIS down Please wait - capturing the traffic"
action 1.1 cli command "enable"
action 1.2 cli command "show clns interface ten0/0/4 | append bootflash:ISIS_DeviceA.txt"
action 1.3 cli command "show clns traffic interface tenGigabitEthernet 0/0/4 | append bootflash:ISIS_DeviceA.txt"
action 2.0 cli command "show logging | append bootflash:debug_DeviceA.txt"
action 2.1 cli command "undebug all"
action 2.2 cli command "monitor capture cap stop"
action 3.0 cli command "end"
For switches to append the logs it is neccesary to use the append flash:, as example:
event manager applet ISIS_Flap authorization bypass event syslog pattern "%CLNS-5-ADJCHANGE:.*hold time expired" action 1.0 syslog msg "ISIS down Please wait - capturing the traffic" action 1.1 cli command "enable" action 1.2 cli command "show clns interface ten0/0/4 | append flash:ISIS_DeviceB.txt"
action 3.0 cli command "end"
8. Una volta attivato il problema, procedere all'esportazione dell'acquisizione su bootflash/flash e verificare che .txt i file vengono archiviati correttamente nello stesso percorso.
DeviceA#monitor capture cap export bootflash:ISIS_DeviceA.pcap Exported Successfully DeviceA#dir bootflash:*.txt Directory of bootflash:/*.txt Directory of bootflash:/ 19 -rw- 6048 Jul 22 2023 13:33:40 +00:00 ISIS_DeviceA.txt 20 -rw- 103153 Jul 22 2023 13:33:40 +00:00 debug_DeviceA.txt 26975526912 bytes total (20527607808 bytes free)
DeviceB#monitor capture cap export location flash:ISIS_DeviceB.pcap
Exported Successfully
DeviceB#dir bootflash:*.txt Directory of bootflash:/*.txt Directory of bootflash:/ 356939 -rw- 660 Jul 22 2023 13:33:42 +00:00 ISIS_DeviceB.txt 356943 -rw- 103283 Jul 22 2023 13:33:42 +00:00 debug_DeviceB.txt
9. Caricare i file su un server TFTP in modo da confrontare i log tra i dispositivi.
DeviceA#copy bootflash:ISIS_DeviceA.txt tftp:
Address or name of remote host []? < TFTP IP address >
Destination filename [ISIS_DeviceA.txt]?
10. Confrontare le clip e i log per verificare se i pacchetti sono stati inviati e ricevuti da entrambi i router.
Analisi dei registri IS-IS:
- Entrambe le interfacce IS-IS sono configurate con lo stesso tipo di rete L1-L2.
- Lo stato Interfacce (se non attivo) indica che entrambe le interfacce non ricevono il pacchetto hello.
- IS-IS: mancata corrispondenza tra i pacchetti inviati e ricevuti da parte di Hellos PTP. Mentre il dispositivo A invia 205 pacchetti e ne riceve 199 dal peer, il dispositivo B ne ha 202 su 202. Ciò indica che il trasporto non è affidabile.
DeviceA
TenGigabitEthernet0/0/4 is up, line protocol is up Attached to: isis Checksums enabled, MTU 1497, Encapsulation SAP ERPDUs enabled, min. interval 10 msec. CLNS fast switching disabled CLNS SSE switching disabled DEC compatibility mode OFF for this interface Next ESH/ISH in 30 seconds Routing Protocol: IS-IS Circuit Type: level-1-2 Interface number 0x0, local circuit ID 0x5 Neighbor Extended Local Circuit ID: 0x0 Level-1 Metric: 10, Priority: 64, Circuit ID: DeviceA.05 Level-1 IPv6 Metric: 10 Number of active level-1 adjacencies: 0 Level-2 Metric: 10, Priority: 64, Circuit ID: DeviceA.05 Level-2 IPv6 Metric: 10 Number of active level-2 adjacencies: 0 Next IS-IS Hello in 574 milliseconds if state DOWN CLNS: Time since last clear: 00:29:37 CLNS & ESIS Output: 33, Input: 241 Dropped Protocol not enabled on interface: 0 CLNS Local: 0, Forward: 0
Interface TenGigabitEthernet0/0/4: IS-IS: Time since last clear: 00:29:37 IS-IS: Level-1 Hellos (sent/rcvd): 0/0 IS-IS: Level-2 Hellos (sent/rcvd): 0/0 IS-IS: PTP Hellos (sent/rcvd): 205/199 IS-IS: Level-1 LSPs flooded (sent/rcvd): 2/2 IS-IS: Level-2 LSPs flooded (sent/rcvd): 2/2 IS-IS: Level-1 CSNPs (sent/rcvd): 0/0 IS-IS: Level-2 CSNPs (sent/rcvd): 0/0 IS-IS: Level-1 PSNPs (sent/rcvd): 2/2 IS-IS: Level-2 PSNPs (sent/rcvd): 2/2 IS-IS: Level-1 DR Elections: 0 IS-IS: Level-2 DR Elections: 0 DeviceB TwentyFiveGigE1/0/9 is up, line protocol is up Attached to: isis Checksums enabled, MTU 1497, Encapsulation SAP ERPDUs enabled, min. interval 10 msec. CLNS fast switching disabled CLNS SSE switching disabled DEC compatibility mode OFF for this interface Next ESH/ISH in 20 seconds Routing Protocol: IS-IS Circuit Type: level-1-2 Interface number 0x0, local circuit ID 0xB Neighbor Extended Local Circuit ID: 0x0 P2P retransmit queue size: 0 Level-1 Metric: 10, Priority: 64, Circuit ID: DeviceB.0B Level-1 IPv6 Metric: 10 Number of active level-1 adjacencies: 0 Level-2 Metric: 10, Priority: 64, Circuit ID: DeviceB.0B Level-2 IPv6 Metric: 10 Number of active level-2 adjacencies: 0 Next IS-IS Hello in 7 seconds if state DOWN CLNS: Time since last clear: 00:29:34 CLNS queue depth: 0/100, drops: 0, highest: 1 CLNS & ESIS Output: 34, Input: 243 Dropped Protocol not enabled on interface: 0 CLNS Local: 0, Forward: 0
Interface TwentyFiveGigE1/0/9: IS-IS: Time since last clear: 00:29:34 IS-IS: Level-1 Hellos (sent/rcvd): 0/0 IS-IS: Level-2 Hellos (sent/rcvd): 0/0 IS-IS: PTP Hellos (sent/rcvd): 202/202 IS-IS: Level-1 LSPs flooded (sent/rcvd): 2/2 IS-IS: Level-2 LSPs flooded (sent/rcvd): 2/2 IS-IS: Level-1 CSNPs (sent/rcvd): 0/0 IS-IS: Level-2 CSNPs (sent/rcvd): 0/0 IS-IS: Level-1 PSNPs (sent/rcvd): 2/2 IS-IS: Level-2 PSNPs (sent/rcvd): 2/2 IS-IS: Level-1 DR Elections: 0 IS-IS: Level-2 DR Elections: 0
Il passaggio successivo è quello di confrontare i debug e le acquisizioni.
DeviceA
Jul 22 19:17:24.929: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15 Jul 22 19:17:24.929: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496 Jul 22 19:17:31.685: ISIS-Adj: Rec serial IIH from 6c31.0edb.3b5f (TenGigabitEthernet0/0/4) Jul 22 19:17:31.685: ISIS-Adj: cir type L1L2, cir id 0B, length 1496 Jul 22 19:17:31.685: ISIS-Adj: rcvd state UP, old state UP, new state UP, nbr usable TRUE Jul 22 19:17:31.685: ISIS-Adj: RCV:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15 Jul 22 19:17:31.685: ISIS-Adj: Nghbr Ckt ID changed: FALSE Jul 22 19:17:31.685: ISIS-Adj: received Neighbor System-ID (must be our) 0000.0000.000A Jul 22 19:17:31.685: ISIS-Adj: received Neighbor ext.circuit ID (must be our) 0x5 Jul 22 19:17:31.685: ISIS-Adj: newstate:0, state_changed:0, going_up:0, going_down:0 Jul 22 19:17:31.685: ISIS-Adj: Action = ACCEPT Jul 22 19:17:31.685: ISIS-Adj: ACTION_ACCEPT: Jul 22 19:17:33.626: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15 Jul 22 19:17:33.627: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496 Jul 22 19:17:42.671: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15 Jul 22 19:17:42.672: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496 Jul 22 19:17:52.008: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15 Jul 22 19:17:52.008: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496 Jul 22 19:18:01.475: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15 Jul 22 19:18:01.475: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496 Jul 22 19:18:01.685: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Down, hold time expired Jul 22 19:18:01.685: ISIS-Adj: L1 adj count 0 Jul 22 19:18:01.685: ISIS-Adj: L2 adj count 0
DeviceB
Jul 22 19:17:25.693: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15
Jul 22 19:17:25.693: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:UP, length 1496
Jul 22 19:17:27.882: ISIS-Adj: Rec serial IIH from a84f.b1c3.9484 (TwentyFiveGigE1/0/9)
Jul 22 19:17:27.882: ISIS-Adj: cir type L1L2, cir id 05, length 1496
Jul 22 19:17:27.882: ISIS-Adj: rcvd state UP, old state UP, new state UP, nbr usable TRUE
Jul 22 19:17:27.882: ISIS-Adj: RCV:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15
Jul 22 19:17:27.882: ISIS-Adj: Nghbr Ckt ID changed: FALSE
Jul 22 19:17:27.882: ISIS-Adj: received Neighbor System-ID (must be our) 0000.0000.000B
Jul 22 19:17:27.882: ISIS-Adj: received Neighbor ext.circuit ID (must be our) 0xB
Jul 22 19:17:27.882: ISIS-Adj: newstate:0, state_changed:0, going_up:0, going_down:0
Jul 22 19:17:27.882: ISIS-Adj: Action = ACCEPT
Jul 22 19:17:27.882: ISIS-Adj: ACTION_ACCEPT:
Jul 22 19:17:34.637: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15
Jul 22 19:17:34.637: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:UP, length 1496
Jul 22 19:17:36.579: ISIS-Adj: Rec serial IIH from a84f.b1c3.9484 (TwentyFiveGigE1/0/9)
Jul 22 19:17:36.579: ISIS-Adj: cir type L1L2, cir id 05, length 1496
Jul 22 19:17:36.579: ISIS-Adj: rcvd state UP, old state UP, new state UP, nbr usable TRUE
Jul 22 19:17:36.579: ISIS-Adj: RCV:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15
Jul 22 19:17:36.579: ISIS-Adj: Nghbr Ckt ID changed: FALSE
Jul 22 19:17:36.579: ISIS-Adj: received Neighbor System-ID (must be our) 0000.0000.000B
Jul 22 19:17:36.579: ISIS-Adj: received Neighbor ext.circuit ID (must be our) 0xB
Jul 22 19:17:36.579: ISIS-Adj: newstate:0, state_changed:0, going_up:0, going_down:0
Jul 22 19:17:36.579: ISIS-Adj: Action = ACCEPT
Jul 22 19:17:36.579: ISIS-Adj: ACTION_ACCEPT:
Jul 22 19:17:43.270: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15
Jul 22 19:17:43.271: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:UP, length 1496
Jul 22 19:17:51.658: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15
Jul 22 19:17:51.658: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:UP, length 1496
Jul 22 19:18:00.248: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15
Jul 22 19:18:00.248: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:UP, length 1496
Jul 22 19:18:06.579: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Down, hold time expired
Jul 22 19:18:06.579: ISIS-Adj: L1 adj count 0
Jul 22 19:18:06.579: ISIS-Adj: L2 adj count 0
Analisi dei log di debug IS-IS:
- Il dispositivo A invia un pacchetto hello (22 lug 19:17:24), il dispositivo B risponde a questo pacchetto (22 lug 19:17:25), il dispositivo A riceve questa risposta (22 lug 19:17:31).
Periferica A
Jul 22 19:17:24.929: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15
Jul 22 19:17:24.929: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496
Jul 22 19:17:31.685: ISIS-Adj: Rec serial IIH from 6c31.0edb.3b5f (TenGigabitEthernet0/0/4)
Periferica B
Jul 22 19:17:25.693: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15
Jul 22 19:17:25.693: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:UP, length 1496
Jul 22 19:17:27.882: ISIS-Adj: Rec serial IIH from a84f.b1c3.9484 (TwentyFiveGigE1/0/9)
- Il dispositivo A invia un altro pacchetto hello (22 lug 19:17:33), il dispositivo B invia il suo pacchetto hello (22 lug 19:17:34) e due secondi dopo riceve il pacchetto dal peer.
Periferica A
Jul 22 19:17:33.626: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15
Jul 22 19:17:33.627: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496
Periferica B
Jul 22 19:17:34.637: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15
Jul 22 19:17:34.637: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:UP, length 1496
Jul 22 19:17:36.579: ISIS-Adj: Rec serial IIH from a84f.b1c3.9484 (TwentyFiveGigE1/0/9)
- Durante il periodo in cui il dispositivo A non riceve il pacchetto inviato dal dispositivo B, il protocollo si dichiara inattivo dopo 30 secondi.
Periferica A
Jul 22 19:17:42.671: ISIS-Adj: SND:3way Adj. Local Ckt ID:0x5 Nghbr Ckt ID:0xB Length:15
Jul 22 19:17:42.672: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496 Jul 22 19:18:01.475: ISIS-Adj: Sending serial IIH on TenGigabitEthernet0/0/4, 3way state:UP, length 1496
Jul 22 19:18:01.685: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceB (TenGigabitEthernet0/0/4) Down, hold time expired
- Il dispositivo B non riceve alcun pacchetto dal peer. Trascorso il periodo di attesa predefinito, il protocollo si dichiara inattivo.
Periferica B
Jul 22 19:17:43.270: ISIS-Adj: SND:3way Adj. Local Ckt ID:0xB Nghbr Ckt ID:0x5 Length:15
Jul 22 19:17:43.271: ISIS-Adj: Sending serial IIH on TwentyFiveGigE1/0/9, 3way state:UP, length 1496
<snip>
Jul 22 19:18:06.579: %CLNS-5-ADJCHANGE: ISIS: Adjacency to DeviceA (TwentyFiveGigE1/0/9) Down, hold time expired
Acquisisce l'analisi:
Il dispositivo A riceve pacchetti dal dispositivo B, ma l'ultimo pacchetto ricevuto dal router dal peer è alle 13:17.31. Il dispositivo A invia quindi i pacchetti Hello
senza alcuna risposta da parte del peer.
ISIS Random Flaps Device A
L'acquisizione sul dispositivo B mostra una condizione simile: lo switch riceve l'ultimo pacchetto hello dal dispositivo peer, ma DeviceB inizia a inviare i pacchetti hello senza risposta.
Dispositivo instabile ISISB
Nelle clip esportate, i pacchetti hello non vengono consegnati tra peer. Il problema sembra riguardare il trasporto.
Cronologia delle revisioni
| Revisione | Data di pubblicazione | Commenti |
|---|---|---|
1.0 |
27-Jul-2023 |
Versione iniziale |
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