Comando Cisco IOS per Verificare lo Stato dell'Interfaccia: show interfaces

Verifica dello Stato dell'Interfaccia su Router/Switch Cisco

Il comando principale è show interfaces (o show interface).

Variazioni di Sintassi

 show interfaces ! Tutte le interfacce dettaglio show interfaces [tipo numero] ! Specifico: show interfaces GigabitEthernet0/1 show interfaces status ! Tabella riassuntiva (switch) show interfaces description ! Descrizione + stato + protocollo show interfaces accounting ! Conteggio pacchetti/byte show interfaces counters errors ! Solo contatori errori show interfaces [tipo numero] brief ! Riepilogo su una riga 

Campi di Output Chiave

• Line Protocol: up (Data Link OK) / down (nessun keepalive, nessun clock).
• Interfaccia: up (Admin up, hardware OK) / down (shutdown) / administratively down.
• Hardware: Tipo, MAC, MTU, BW, Delay, Reliability, Load, Encapsulation.
• Indirizzo Internet: IP/mask.
• Contatori: Pacchetti/byte input/output, drop, errori (CRC, frame, overrun, ignored), collisioni, reset.
• Coda: Coda output, drop, conversazioni.
• Velocità: Tasso input/output 5 min (bit/sec, pacchetti/sec).

Esempio di Output (GigabitEthernet0/1)

 GigabitEthernet0/1 is up, line protocol is up Hardware is CSR vNIC, address is 0050.568e.1234 (bia 0050.568e.1234) Internet address is 192.168.1.1/24 MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set Keepalive set (10 sec) Full Duplex, 1000Mbps, media type is RJ45 input flow-control is off, output flow-control off ARP type: ARPA, ARP Timeout 04:00:00 Last input 00:00:00, output 00:00:00, output hang never Last clearing of "show interface" counters never Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 Queueing strategy: fifo Output queue: 0/40 (size/max) 5 minute input rate 1000 bits/sec, 2 packets/sec 5 minute output rate 2000 bits/sec, 3 packets/sec 1500 packets input, 120000 bytes, 0 no buffer Received 1000 broadcasts, 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored 0 watchdog, 0 multicast, 0 pause input 1800 packets output, 150000 bytes, 0 underruns 0 output errors, 0 collisions, 1 interface resets 0 unknown protocol drops 0 output buffer failures, 0 output buffers swapped out 

Controllo Rapido dello Stato

• show interfaces | include (up|down|errors|rate)
• show interfaces status (switch): Porta, Nome, Stato, Vlan, Duplex, Velocità, Tipo.

Essenziale per risolvere problemi di connettività, prestazioni, errori e pianificazione capacità.