# Question about dietpi-backup, usb drive and ext4 format
**URL:** https://dietpi.com/forum/t/question-about-dietpi-backup-usb-drive-and-ext4-format/270
**Category:** Troubleshooting
**Created:** [25 February 2016 17:15 UTC](https://dietpi.com/forum/t/question-about-dietpi-backup-usb-drive-and-ext4-format/270 "2016-02-25T17:15:23Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@skyfly555](https://dietpi.com/forum/u/skyfly555)
#### Post date: [25 February 2016 17:15 UTC](https://dietpi.com/forum/t/question-about-dietpi-backup-usb-drive-and-ext4-format/270/1 "2016-02-25T17:15:23Z")
It’s needed a USB drive with ext4 format to use dietpi-backup.
So I’ve taken my vfat usb drive, ubicated with
```nohighlight
df -h
```
, unmounted with
```nohighlight
umount /dev/sda1
```
and formatted with
```nohighlight
mkfs.ext4 /dev/sda1
```
. Then I can go into it in
```nohighlight
/mnt/usb_1
```
.
What happens:
1- Maybe dietpi-backup says it’s read only.
2- Maybe during the formatting process I get an error.
I’ve tried, after formatting it, edit "
```nohighlight
/etc/fstab
```
" and uncommenting the line:
```nohighlight
/dev/sda1 /mnt/usb_1 ext4 defaults,noatime,nofail 0 0
```
And commenting the line:
```nohighlight
#/dev/sda1 /mnt/usb_1 vfat defaults,noatime,nofail 0 0
```
And, after that, rebooting.
The time the process has gone better, the USB drive has been formatted without any error messages, dietpi-backup supposedly has done its job and the pendrive has been detected after dietpi-backup, but
```nohighlight
df -h
```
has said it’s only used 60 M when it should be 1 G approx.
After rebooting, the pendrive hasn’t been detected.
I’ve read on forums than they talk about permissions and so on, but I don’t know what I’m doing wrong.
**Please, can you give me some light? I suppose I’m not formatting the USB drive correctly.**
Thank you very much,
---
### Author:  [@skyfly555](https://dietpi.com/forum/u/skyfly555)
#### Post date: [25 February 2016 18:03 UTC](https://dietpi.com/forum/t/question-about-dietpi-backup-usb-drive-and-ext4-format/270/2 "2016-02-25T18:03:42Z")
Looking at /var/log/dietpi-backup.log, it ends:
```nohighlight
2016/02/25 17:56:00 [2668] rsync: write failed on "/mnt/usbdrive/build/php5-5.6.17+dfsg/pear-build-download/turba-4.2.12.tgz": Input/output error (5)
2016/02/25 17:56:00 [2668] rsync: failed to set times on "/mnt/usbdrive/build/php5-5.6.17+dfsg/pear-build-download/.turba-4.2.12.tgz.NK7Ilf": Read-only file system (30)
2016/02/25 17:56:00 [2668] rsync: rename "/mnt/usbdrive/build/php5-5.6.17+dfsg/pear-build-download/.turba-4.2.12.tgz.NK7Ilf" -> "build/php5-5.6.17+dfsg/pear-build-download/turba-4.2.12.t$
2016/02/25 17:56:00 [2668] rsync error: error in file IO (code 11) at receiver.c(393) [receiver=3.1.1]
```
---
### Author:  [@Fourdee](https://dietpi.com/forum/u/Fourdee)
#### Post date: [25 February 2016 21:05 UTC](https://dietpi.com/forum/t/question-about-dietpi-backup-usb-drive-and-ext4-format/270/3 "2016-02-25T21:05:25Z")
> [@skyfly555](#):
>
> df -has said it’s only used 60 M when it should be 1 G approx.
Sounds like you didn’t clear the partition table before formatting
Heres the code that /DietPi/dietpi/dietpi-external\_drive\_setup uses:
```plaintext
#Unmount all connected drives
umount /dev/sd[a-z][1-9]
#Clear MBR and partition table from device
dd if=/dev/zero of=/dev/sda bs=512 count=1
#Create New partition on /dev/sda
echo -e "o\nn\np\n1\n\n\nw" | fdisk /dev/sda
#Format ext4
umount /dev/sd[a-z][1-9]
echo -e "y" | mkfs.ext4 /dev/sda1
resize2fs /dev/sda1
mount -a
chown -R root:root /mnt/usb_1
```
You can also run the following script to format/setup your USB drive:
```plaintext
/DietPi/dietpi/dietpi-external_drive_setup
```
---
### Author:  [@skyfly555](https://dietpi.com/forum/u/skyfly555)
#### Post date: [28 February 2016 01:15 UTC](https://dietpi.com/forum/t/question-about-dietpi-backup-usb-drive-and-ext4-format/270/4 "2016-02-28T01:15:25Z")
Thank you very much.
Perfect!