IOS基本操作和配置（一）

进入特权模式

enable

退出特权模式

disable

进入全局模式

configure terminal

进入接口模式

interface fastEthernet 0/1

查看软硬件信息(寄存器值)

R1#show version

R1#show version
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-J1S3-M), Version 12.3(26), RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2008 by cisco Systems, Inc.
Compiled Mon 17-Mar-08 15:23 by dchih

ROM: ROMMON Emulation Microcode
ROM: C2600 Software (C2600-J1S3-M), Version 12.3(26), RELEASE SOFTWARE (fc2)

R1 uptime is 4 minutes
System returned to ROM by unknown reload cause - suspect boot_data[BOOT_COUNT] 0x0, BOOT_COUNT 0, BOOTDATA 19
System image file is "tftp://255.255.255.255/unknown"

cisco 2621 (MPC860) processor (revision 0x202) with 56320K/9216K bytes of memory.
Processor board ID FTX0945W0MY (4279256517)
M860 processor: part number 0, mask 0
Bridging software.
X.25 software, Version 3.0.0.
TN3270 Emulation software.
2 FastEthernet/IEEE 802.3 interface(s)
128K bytes of non-volatile configuration memory.
8192K bytes of processor board System flash (Read/Write)

Configuration register is 0x2102

IOS解释：flsah可以放很多的IOS。默认是从第一个IOS启动，第一个启动不了启动第二个。IOS应该有2个,最小的IOS 1M~2M放在ROM里面，ROM是不可擦也不可写的。提供最基本的IOS恢复功能。

查看运行的配置文件

Switch#show running-config

解释：running-config是存在NVRAM里面的，当IOS启动的时候把NVRAM里面的running-config拷贝到RAM里面去运行，Switch#show running-config是调用RAM里面的配置文件

查看NVRAM配置文件

Switch#show startup-config

查看所有接口的信息

Switch#show interfaces

查看指定接口的信息

Switch#show interfaces FastEthernet 0/1

FastEthernet0/1 is down, line protocol is down (disabled)
Hardware is Lance, address is 0050.0fac.b501 (bia 0050.0fac.b501)
BW 100000 Kbit, DLY 1000 usec,

解释：0/1 0代表第几模块，1代表模块里面的第几个接口