设备有密码
首先在开机的时候按住交换机左下边的mode键 交换机将进入监控模式 switch:
在监控模式下
switch:flash_init 初始化闪存
switch:load_helper 装入程序
switch:dir flash: 查看 文件名 (配置文件)
switch:rename flash:config.text flash config.back
switch:boot

重启后进入用户模式 再进入特权模式

switch#rename flash:config.back flash:config.text
switch#copy flash:config.text system:running-config
进入全局模式后 修改密码 enable secret cisco 然后退出全局模式
copy run start 修改为启动配置 然后reload
过程
按mode
Base ethernet MAC Address: 00:1b:54:ad:3f:80
Xmodem file system is available.
The password-recovery mechanism is enabled.

The system has been interrupted prior to initializing the
flash filesystem.  The following commands will initialize
the flash filesystem, and finish loading the operating
system software:

    flash_init
    load_helper
    boot

switch:

switch: flash_init
Initializing Flash...
flashfs[0]: 600 files, 19 directories
flashfs[0]: 0 orphaned files, 0 orphaned directories
flashfs[0]: Total bytes: 32514048
flashfs[0]: Bytes used: 7714304
flashfs[0]: Bytes available: 24799744
flashfs[0]: flashfs fsck took 10 seconds.
...done Initializing Flash.
Boot Sector Filesystem (bs) installed, fsid: 3
Setting console baud rate to 9600...

switch: load_helper 

switch: dir flash:
Directory of flash:/

2    -rwx  796       <date>               vlan.dat
4    -rwx  3267      <date>               config.text
5    drwx  192       <date>               c2960-lanbase-mz.122-25.SEE2
620  -rwx  5         <date>               private-config.text

24799744 bytes available (7714304 bytes used)

switch: rename flash:config.text flash:config.back

switch: boot
Loading "flash:c2960-lanbase-mz.122-25.SEE2/c2960-lanbase-mz.122-25.SEE2.bin"...@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
File "flash:c2960-lanbase-mz.122-25.SEE2/c2960-lanbase-mz.122-25.SEE2.bin" uncompressed and installed, entry point: 0x3000
executing...

              Restricted Rights Legend

Use, duplication, or disclosure by the Government is
subject to restrictions as set forth in subparagraph
(c) of the Commercial Computer Software - Restricted
Rights clause at FAR sec. 52.227-19 and subparagraph
(c) (1) (ii) of the Rights in Technical Data and Computer
Software clause at DFARS sec. 252.227-7013.

           cisco Systems, Inc.
           170 West Tasman Drive
           San Jose, California 95134-1706

Cisco IOS Software, C2960 Software (C2960-LANBASE-M), Version 12.2(25)SEE2, RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2006 by Cisco Systems, Inc.
Compiled Fri 28-Jul-06 04:33 by yenanh
Image text-base: 0x00003000, data-base: 0x00AA2F34

Initializing flashfs...

flashfs[1]: 600 files, 19 directories
flashfs[1]: 0 orphaned files, 0 orphaned directories
flashfs[1]: Total bytes: 32514048
flashfs[1]: Bytes used: 7714304
flashfs[1]: Bytes available: 24799744
flashfs[1]: flashfs fsck took 1 seconds.
flashfs[1]: Initialization complete....done Initializing flashfs.

POST: CPU MIC register Tests : Begin
POST: CPU MIC register Tests : End, Status Passed

POST: PortASIC Memory Tests : Begin
POST: PortASIC Memory Tests : End, Status Passed

POST: CPU MIC PortASIC interface Loopback Tests : Begin
POST: CPU MIC PortASIC interface Loopback Tests : End, Status Passed

POST: PortASIC RingLoopback Tests : Begin
POST: PortASIC RingLoopback Tests : End, Status Passed

POST: PortASIC CAM Subsystem Tests : Begin
POST: PortASIC CAM Subsystem Tests : End, Status Passed

POST: PortASIC Port Loopback Tests : Begin
POST: PortASIC Port Loopback Tests : End, Status Passed

Waiting for Port download...Complete

cisco WS-C2960G-24TC-L (PowerPC405) processor (revision C0) with 61440K/4088K bytes of memory.
Processor board ID FOC1112Z87J
Last reset from power-on
1 Virtual Ethernet interface
24 Gigabit Ethernet interfaces
The password-recovery mechanism is enabled.

64K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address       : 00:1B:54:AD:3F:80
Motherboard assembly number     : 73-10015-05
Power supply part number        : 341-0098-02
Motherboard serial number       : FOC11120WB5
Power supply serial number      : AZS11021477
Model revision number           : C0
Motherboard revision number     : B0
Model number                    : WS-C2960G-24TC-L
System serial number            : FOC1112Z87J
Top Assembly Part Number        : 800-26673-02
Top Assembly Revision Number    : D0
Version ID                      : V02
CLEI Code Number                : COM3G00BRA
Hardware Board Revision Number  : 0x01

Switch   Ports  Model              SW Version              SW Image           
------   -----  -----              ----------              ----------         
*    1   24     WS-C2960G-24TC-L   12.2(25)SEE2            C2960-LANBASE-M    

Press RETURN to get started!
Would you like to terminate autoinstall? [yes]: n

         --- System Configuration Dialog ---

Would you like to enter the initial configuration dialog? [yes/no]: n

Would you like to terminate autoinstall? [yes]: n
Switch>
00:04:18: %LINK-5-CHANGED: Interface Vlan1, changed state to administratively down
Switch>
Switch>
Switch>
Switch>en  现在可以直接进特权模式了
Switch#
Switch#rename flash:config.back flash:config.text
Destination filename [config.text]?
Switch#copy flash:config.text sys
Switch#copy flash:config.text system:running-config
Destination filename [running-config]?

3267 bytes copied in 0.277 secs (11794 bytes/sec)
NB-C2960-36#
00:07:32: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan6, changed state to down
NB-C2960-36#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
NB-C2960-36(config)#enable secret cisco
The enable secret you have chosen is the same as your enable password.
This is not recommended.  Re-enter the enable secret.
NB-C2960-36(config)#exit
NB-C2960-36#co
00:08:52: %SYS-5-CONFIG_I: Configured from console by console 
% Ambiguous command:  "co"
NB-C2960-36#
NB-C2960-36#copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
NB-C2960-36#

重启后的配置 版本信息

NB-C2960-36#sh ver
Cisco IOS Software, C2960 Software (C2960-LANBASE-M), Version 12.2(25)SEE2, RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2006 by Cisco Systems, Inc.
Compiled Fri 28-Jul-06 04:33 by yenanh
Image text-base: 0x00003000, data-base: 0x00AA2F34

ROM: Bootstrap program is C2960 boot loader
BOOTLDR: C2960 Boot Loader (C2960-HBOOT-M) Version 12.2(25r)SEE1, RELEASE SOFTWARE (fc1)

NB-C2960-36 uptime is 12 minutes
System returned to ROM by power-on
System image file is "flash:c2960-lanbase-mz.122-25.SEE2/c2960-lanbase-mz.122-25.SEE2.bin"

cisco WS-C2960G-24TC-L (PowerPC405) processor (revision C0) with 61440K/4088K bytes of memory.
Processor board ID FOC1112Z87J
Last reset from power-on
2 Virtual Ethernet interfaces
24 Gigabit Ethernet interfaces
The password-recovery mechanism is enabled.

64K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address       : 00:1B:54:AD:3F:80
Motherboard assembly number     : 73-10015-05
Power supply part number        : 341-0098-02
Motherboard serial number       : FOC11120WB5
Power supply serial number      : AZS11021477
Model revision number           : C0
Motherboard revision number     : B0
Model number                    : WS-C2960G-24TC-L
System serial number            : FOC1112Z87J
Top Assembly Part Number        : 800-26673-02
Top Assembly Revision Number    : D0
Version ID                      : V02
CLEI Code Number                : COM3G00BRA
Hardware Board Revision Number  : 0x01

Switch   Ports  Model              SW Version              SW Image           
------   -----  -----              ----------              ----------         
*    1   24     WS-C2960G-24TC-L   12.2(25)SEE2            C2960-LANBASE-M    

Configuration register is 0xF

NB-C2960-36#sh run
Building configuration...

Current configuration : 3267 bytes
!
version 12.2
no service pad
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname NB-C2960-36
!
enable secret 5 $1$kun9$XOMeTXYWJarcwE5vSGpZ20
enable password 7 045802150C2E
!
no aaa new-model
vtp mode transparent
ip subnet-zero
!
!
!
!
no file verify auto
spanning-tree mode pvst
spanning-tree extend system-id
!
vlan internal allocation policy ascending
!
vlan 6-7
!
vlan 8
 name lan8
!
vlan 9
 name lan9
!
interface GigabitEthernet0/1
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/2
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/3
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/4
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/5
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/6
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/7
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!        
interface GigabitEthernet0/8
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/9
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/10
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/11
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/12
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/13
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/14
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/15
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/16
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/17
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/18
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/19
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/20
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/21
 switchport mode access
 spanning-tree portfast
!        
interface GigabitEthernet0/22
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/23
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet0/24
 description To SW99.230
 switchport access vlan 8
 switchport mode access
 spanning-tree portfast
!
interface Vlan1
 no ip address
 no ip route-cache
 shutdown
!
interface Vlan6
 ip address 192.168.99.250 255.255.255.0
 no ip route-cache
!
ip http server
!
control-plane
!
!
line con 0
line vty 0 4
 password 7 06535E37404F070E1200
 login
line vty 5 15
 password 7 115C48131B13051B133D
 login
!
end

NB-C2960-36# 

开启日志记录
全局模式下 logging on
全局模式下 logging buffered 7(最高的级别日志)