1.用串口线连接博科FC交换机设备
2.重新启动博科FC交换机
3.当终端软件显示下面内容时，按ESC键
Checking system RAM - press any key tostop test
Checking memory address: 00100000
System RAM test terminated by keyboard
set_bootstatus: BS_LOAD_OS, platform_idx= 6
Hit ESC to stop autoboot: 0
4.按ESC键后进入以下界面，选择3
5.注意
如果提示您输入一个新的启动密码,确保它是至少8个字符在长度。不要选择这个选项,除非专业人员。
6.输入
setenv OSLoadOptions "single" 改变用户模式
7.输入
printenv来验证变化
查看printenc输出选项中，OSLoadOptions选项的值是single
8.如果输出无误，则输入
saveenv来保存配置
9.输入
boot命令进入单用户模式（输入下面红色字体的命令）
Enter the boot command withno parameters to bring up the device in single-user mode:
=> boot
Map file at LBA sector 0x17da68
## Booting image at 00400000 ...
(output truncated) mount -o remount,rw /
Enterthe mount command with the following parameters to remount the root partitionas read/write capable:
sh-2.04# mount -o remount,rw /
EXT3 FS on hda1, internal journal
Mountthe secondary partition.
If the previous command returns hda2, thenuse hda1 in this command. If the previous command returns hda 1, use hda2.
sh-2.04# mount /dev/hda2 /mnt
kjournald starting. Commit interval 5 seconds
EXT3 FS on hda2, internal journal
EXT3-fs: mounted filesystem with ordered data mode.
Enterthe passwddefault command to reset all passwords to default values as follows:
sh-2.04# /sbin/passwddefault
All account passwords have been successfully set to factory default.
If additional user accounts existed, they are deleted. Only the defaultaccounts and passwords remain.
Resetthe OSLoadOptions to “quiet;quiet”,Password recovery using the Boot PROM interface
sh-2.04# bootenv OSLoadOptions ”quiet;quiet”
Rebootthe switch by using the reboot –f command.
sh-2.04# reboot -f
待设备重启后，即完成密码重置，输入默认密码登录即可