På samma sätt som vi använder olika verktyg och kommandon för att verifiera en värddators konfiguration, kan vi även använda show-kommandon för att kontrollera status och funktion på routrar och switchar.
Cisco IOS innehåller ett stort antal show-kommandon som visar detaljerad information om hur enheten är konfigurerad och hur den fungerar i drift.
Show-kommandon är några av de mest använda verktygen för nätverkstekniker. De används för att:
- visa och granska konfigurationsfiler,
- kontrollera status för interface och processer,
- samt verifiera att enheten fungerar som den ska.
Nästan varje process eller funktion i en router kan övervakas eller verifieras med hjälp av ett show-kommando.
Vanliga show-kommandon
| Kommando | Används för |
|---|---|
show running-config |
För att verifiera aktuell konfiguration och inställningar |
show interfaces |
För att kontrollera gränssnittens status och eventuella felmeddelanden |
show ip interface |
För att visa information på lager 3 för ett gränssnitt |
show arp |
För att se listan över kända värdar på lokala Ethernet-nätverk |
show ip route |
För att verifiera routinginformationen på lager 3 |
show protocols |
För att se vilka protokoll som är aktiva |
show version |
För att visa enhetens minne, gränssnitt och licenser |
Obs: I exemplen nedan har vissa delar av utdata förkortats för tydlighetens skull.
- show running-config
- show interfaces
- show ip interface
- show arp
- show ip route
- show protocols
- show version
show running-config
Visar den aktuella konfigurationen och alla inställningar på enheten.
R1# show running-config (Output omitted) ! version 15.5 service timestamps debug datetime msec service timestamps log datetime msec service password-encryption ! hostname R1 ! interface GigabitEthernet0/0/0 description Link to R2 ip address 209.165.200.225 255.255.255.252 negotiation auto ! interface GigabitEthernet0/0/1 description Link to LAN ip address 192.168.10.1 255.255.255.0 negotiation auto ! router ospf 10 network 192.168.10.0 0.0.0.255 area 0 network 209.165.200.224 0.0.0.3 area 0 ! banner motd ^C Authorized access only! ^C ! line con 0 password 7 14141B180F0B login line vty 0 4 password 7 00071A150754 login transport input telnet ssh ! end R1#
show interfaces
Visar status för gränssnitten och eventuella felmeddelanden.
R1# show interfaces
GigabitEthernet0/0/0 is up, line protocol is up
Hardware is ISR4321-2x1GE, address is a0e0.af0d.e140 (bia a0e0.af0d.e140)
Description: Link to R2
Internet address is 209.165.200.225/30
MTU 1500 bytes, BW 100000 Kbit/sec, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Full Duplex, 100Mbps, link type is auto, media type is RJ45
output flow-control is off, input flow-control is off
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:01, output 00:00:21, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
5127 packets input, 590285 bytes, 0 no buffer
Received 29 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 5043 multicast, 0 pause input
1150 packets output, 153999 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
1 lost carrier, 0 no carrier, 0 pause output
0 output buffer failures, 0 output buffers swapped out
GigabitEthernet0/0/1 is up, line protocol is up
(Output omitted))
show ip interface
Visar information på lager 3 för ett gränssnitt – till exempel IP-adress, mask och aktiva funktioner.
R1# show ip interface
GigabitEthernet0/0/0 is up, line protocol is up
Internet address is 209.165.200.225/30
Broadcast address is 255.255.255.255
Address determined by setup command
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is disabled
Multicast reserved groups joined: 224.0.0.5 224.0.0.6
Outgoing Common access list is not set
Outgoing access list is not set
Inbound Common access list is not set
Inbound access list is not set
Proxy ARP is enabled
Local Proxy ARP is disabled
Security level is default
Split horizon is enabled
ICMP redirects are always sent
ICMP unreachables are always sent
ICMP mask replies are never sent
IP fast switching is enabled
IP Flow switching is disabled
IP CEF switching is enabled
IP CEF switching turbo vector
IP Null turbo vector
Associated unicast routing topologies:
Topology "base", operation state is UP
IP multicast fast switching is enabled
IP multicast distributed fast switching is disabled
IP route-cache flags are Fast, CEF
Router Discovery is disabled
IP output packet accounting is disabled
IP access violation accounting is disabled
TCP/IP header compression is disabled
RTP/IP header compression is disabled
Probe proxy name replies are disabled
Policy routing is disabled
Network address translation is disabled
BGP Policy Mapping is disabled
Input features: MCI Check
IPv4 WCCP Redirect outbound is disabled
IPv4 WCCP Redirect inbound is disabled
IPv4 WCCP Redirect exclude is disabled
GigabitEthernet0/0/1 is up, line protocol is up
(Output omitted)
show arp
Visar listan över kända värdar på de lokala Ethernet-LAN:en.
R1# show arp Protocol Address Age (min) Hardware Addr Type Interface Internet 192.168.10.1 - a0e0.af0d.e141 ARPA GigabitEthernet0/0/1 Internet 192.168.10.10 95 c07b.bcc4.a9c0 ARPA GigabitEthernet0/0/1 Internet 209.165.200.225 - a0e0.af0d.e140 ARPA GigabitEthernet0/0/0 Internet 209.165.200.226 138 a03d.6fe1.9d90 ARPA GigabitEthernet0/0/0 R1#
show ip route
Visar routingtabellen, det vill säga lager 3-information om hur paket ska dirigeras i nätverket.
R1# show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP
a - application route
+ - replicated route, % - next hop override, p - overrides from PfR
Gateway of last resort is 209.165.200.226 to network 0.0.0.0
O*E2 0.0.0.0/0 [110/1] via 209.165.200.226, 02:19:50, GigabitEthernet0/0/0
10.0.0.0/24 is subnetted, 1 subnets
O 10.1.1.0 [110/3] via 209.165.200.226, 02:05:42, GigabitEthernet0/0/0
192.168.10.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.10.0/24 is directly connected, GigabitEthernet0/0/1
L 192.168.10.1/32 is directly connected, GigabitEthernet0/0/1
209.165.200.0/24 is variably subnetted, 3 subnets, 2 masks
C 209.165.200.224/30 is directly connected, GigabitEthernet0/0/0
L 209.165.200.225/32 is directly connected, GigabitEthernet0/0/0
O 209.165.200.228/30
[110/2] via 209.165.200.226, 02:07:19, GigabitEthernet0/0/0
R1#
show protocols
Visar vilka nätverksprotokoll som är aktiva och status för varje gränssnitt.
R1# show protocols Global values: Internet Protocol routing is enabled GigabitEthernet0/0/0 is up, line protocol is up Internet address is 209.165.200.225/30 GigabitEthernet0/0/1 is up, line protocol is up Internet address is 192.168.10.1/24 Serial0/1/0 is down, line protocol is down Serial0/1/1 is down, line protocol is down GigabitEthernet0 is administratively down, line protocol is down R1#
show version
Visar detaljer om enhetens minne, gränssnitt, operativsystemversion och licenser.
R1# show version
Cisco IOS XE Software, Version 03.16.08.S - Extended Support Release
Cisco IOS Software, ISR Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 15.5(3)S8, RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2018 by Cisco Systems, Inc.
Compiled Wed 08-Aug-18 10:48 by mcpre
(Output omitted)
ROM: IOS-XE ROMMON
R1 uptime is 2 hours, 25 minutes
Uptime for this control processor is 2 hours, 27 minutes
System returned to ROM by reload
System image file is "bootflash:/isr4300-universalk9.03.16.08.S.155-3.S8-ext.SPA.bin"
Last reload reason: LocalSoft
(Output omitted)
Technology Package License Information:
-----------------------------------------------------------------
Technology Technology-package Technology-package
Current Type Next reboot
------------------------------------------------------------------
appxk9 appxk9 RightToUse appxk9
uck9 None None None
securityk9 securityk9 Permanent securityk9
ipbase ipbasek9 Permanent ipbasek9
cisco ISR4321/K9 (1RU) processor with 1647778K/6147K bytes of memory.
Processor board ID FLM2044W0LT
2 Gigabit Ethernet interfaces
2 Serial interfaces
32768K bytes of non-volatile configuration memory.
4194304K bytes of physical memory.
3207167K bytes of flash memory at bootflash:.
978928K bytes of USB flash at usb0:.
Configuration register is 0x2102
R1#