群晖NAS不丢失数据重装系统

Quickly Reset the Hard Disk in your QNAP Device as New

In the next few months, I am going to port  ZurmoCRM  onto  QNAP . I might need to test different configuration and need to reinstall  QTS  several times. Remove the hard disk and use SATA to USB bridge to kill partition takes too much time. Instead, you may  SSH  to login, then clean  QTS  partition with  dd . or remove with  fdisk .

Login to QNAP with SSH

ssh-keygen -R 10.42.0.12 -f /home/amigo/.ssh/known_hosts

Remove RSA key with previous QTS if necessary. Please use your NAS IP to replace 10.42.0.12, and user home directory for /home/amigo.

ssh [email protected]

Login as admin which is the same as your web admin account and password.

Fill Null to Disk

df

List of free disk of mounted device to identify the device name of your hard drive in NAS.

dd if=/dev/zero of=/dev/sda bs=10M count=10

/dev/zero is a special file with null characters only. Used as source as a character stream for initializing data storage.
bs=10M means read and write up to 10M bytes at a time.
count=10 means repeat for 10 input blocks.
It will write 10M * 10 data to the beginning of /dev/sda which shall destroy QTS.

Then reboot with reboot command. Now, it shall reinstall QTS firmware automatically.

Remove QTS Partition and Keep Data

There is an alternative and better solution to keep your data which stores in another partition. Instead of dd, use fdisk to work on partition directly.

First to check what is available in disk. Here is a sample executing fdisk -p /dev/sdafrom my QNAP TS-112.

[/sbin] # fdisk -p /dev/sda     

Disk /dev/sda: 2000.3 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1               1          66      530125   83  Linux
/dev/sda2              67         132      530142   83  Linux
/dev/sda3             133      243138  1951945693   83  Linux
/dev/sda4          243139      243200      498012   83  Linux

-p to display partition in a disk.
/dev/sda is the disk name.

Then delete QTS partition by executing fdisk -d 1 /dev/sda.

[/sbin] # fdisk -d 1 /dev/sda
The partition table has been altered!

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.

-d 1 to delete the first partition.
/dev/sda is the disk name.

Then reboot with reboot command. After reboot, it will prompt to install QTSfirmware. Choose [Manual Setup], and click on [Configure disks later] in [Disk] step. It will automaticall to apply settings and reboot.

After reboot, login to QNAP device, re-enable [Microsoft Networking]. Now, you may see your data in the same folder before re-install QTS.

Reference

1. ZurmoCRM
2. QNAP
3. QNAP: QTS 4.0
4. Wiki: Secure Shell
5. LinuxQuestions.org: Fdisk
6. Wiki: df (Unix)
7. Wiki: dd (Unix)
8. Wiki: /dev/zero
9. Mobile01: 從零開始 – 如何重新安裝 QNap NAS 作業系統
10. QNAP TS-112