交换机密码恢复

本实验以WS-3550-48 SMI为例，详细描述对于2900xl/3500xl/2950/3550系列交换机的密码恢复流程
一、将一台终端或装有超级终端软件的PC接到交换机的console口上。终端参数设置如下：
速率：9600bps
校验位：无
数据位：8
停止位：1
流控：无
二、拨掉电源
三、按住前面板的mode键不放，插上电源，等3－5秒后松开mode键。你会看到如下提示：
Interrupt within 5 seconds to abort boot process.
Boot process terminated.
The system is unable to boot automatically. The BOOT
environment variable needs to be set to a bootable
image.
switch:
switch: ?
? -- Present list of available commands
boot -- Load and boot an executable image
cat -- Concatenate (type) file(s)
copy -- Copy a file
delete -- Delete file(s)
dir -- List files in directories
flash_init -- Initialize flash filesystem(s)
format -- Format a filesystem
fsck -- Check filesystem consistency
help -- Present list of available commands
load_helper -- Load and initialize a helper image
memory -- Present memory heap utilization information
mkdir -- Create dir(s)
more -- Concatenate (display) file(s)
rename -- Rename a file
reset -- Reset the system
rmdir -- Delete empty dir(s)
set -- Set or display environment variables
set_param -- Set system parameters in flash
sleep -- Pause (sleep) for a specified number of seconds
trap -- Cause a software breakpoint to occur
-- MORE --
type -- Concatenate (type) file(s)
unset -- Unset one or more environment variables
四、输入flash_init //初始化flash文件系统
五、输入load _helper
六、输入dir flash:
注意，不要少了flash后面的冒号，屏幕出现如下提示。
Directory of flash:/
3 -rwx 0 <date> env_vars
4 -rwx 344 <date> system_env_vars
5 -rwx 3624 <date> config.text
6 -rwx 5 <date> private-config.text
8 drwx 192 <date> c3550-i9q3l2-mz.121-14.EA1a
86 -rwx 5 <date> private-config.text.renamed
10243584 bytes available (5755392 bytes used)
七、输入rename flash:config.text flash:config.old
switch: rename flash:config.text flash:config.old
八、输入boot引导系统。
switch: boot
Loading "flash:c3550-i9q3l2-mz.121-14.EA1a/c3550-i9q3l2-mz.121-14.EA1a.bin"...##############################################################################################################################################################################################################################################################################################################################################################################################################
File "flash:c3550-i9q3l2-mz.121-14.EA1a/c3550-i9q3l2-mz.121-14.EA1a.bin" uncompressed and installed, entry point: 0x3000
executing...

九、当出现如下提示时，输入N：
Continue with the configuration dialog? [yes/no] : N
十、用en进入enable状态，并将文件config.old改回config.text，命令如下：
rename flash:config.old flash:config.text
十一、将原配置装入内存，命令如下：
switch# copy flash:config.text system:running-config
十二、修改密码：
switch#conf t