Raspberry Pi: Setting up backup

I have a Raspberry Pi providing household automation and productivity services – WebDav, Backups and Calendar. I always worry about a jolt of power, a failed byte and something that is unrecoverable. Time for a Backup solution.

I plugged in a USB stick – 64GB, and immediately checked the file system is there and visible as SDA (unmounted).

pi@raspberrypi:~# sudo su - 

root@raspberrypi:~# lsblk 
 sda           8:0    1 58.2G  1 disk 
 └─sda1        8:1    1 58.2G  1 part 
 mmcblk0     179:0    0 14.9G  0 disk 
 ├─mmcblk0p1 179:1    0 43.9M  0 part /boot
 └─mmcblk0p2 179:2    0 14.8G  0 part /

I check to see which one is assigned to the SD card slot (mmc), I really don’t want to reformat Raspbian.  I see the USB stick is on /dev/sda. All of my subsequent commands use /dev/sda as part of the command.

root@raspberrypi:~# parted -ls
Warning: The driver descriptor says the physical block size is 2048 bytes, but Linux says it is 512 bytes.
 Model: JetFlash Transcend 64GB (scsi)
 Disk /dev/sda: 62.5GB
 Sector size (logical/physical): 512B/512B
 Partition Table: unknown
 Disk Flags: 

 Model: SD SC16G (sd/mmc)
 Disk /dev/mmcblk0: 15.9GB
 Sector size (logical/physical): 512B/512B
 Partition Table: msdos
 Disk Flags: 
 Number  Start   End     Size    Type     File system  Flags
  1      4194kB  50.2MB  46.0MB  primary  fat32        lba
  2      50.3MB  15.9GB  15.9GB  primary  ext4

If you don’t see the relevant information on your HD or run into issues formatting the hard-drive, install hdparm.  and check with hdparm -r0 /dev/sda  .

TIP: I did run into an issue with an ISO written to a USB drive which locks the partition table and makes it unwriteable.

root@raspberrypi:~# apt-get install hdparm
 Reading package lists… Done
 Building dependency tree       
 Reading state information… Done
 The following package was automatically installed and is no longer required:
 Use 'apt autoremove' to remove it.
 The following additional packages will be installed:
 Suggested packages:
 The following NEW packages will be installed:
   hdparm powermgmt-base
 0 upgraded, 2 newly installed, 0 to remove and 148 not upgraded.
 Need to get 114 kB of archives.
 After this operation, 278 kB of additional disk space will be used.
 Do you want to continue? [Y/n] y
 Get:1 http://raspbian.mirror.constant.com/raspbian stretch/main armhf hdparm armhf 9.51+ds-1+deb9u1 [105 kB]
 Get:2 http://raspbian-us.ngc292.space/raspbian stretch/main armhf powermgmt-base all 1.31+nmu1 [9,240 B]
 Fetched 114 kB in 0s (120 kB/s)           
 Selecting previously unselected package hdparm.
 (Reading database … 135688 files and directories currently installed.)
 Preparing to unpack …/hdparm_9.51+ds-1+deb9u1_armhf.deb …
 Unpacking hdparm (9.51+ds-1+deb9u1) …
 Selecting previously unselected package powermgmt-base.
 Preparing to unpack …/powermgmt-base_1.31+nmu1_all.deb …
 Unpacking powermgmt-base (1.31+nmu1) …
 Setting up powermgmt-base (1.31+nmu1) …
 Setting up hdparm (9.51+ds-1+deb9u1) …
 Processing triggers for man-db ( …
Preparing to unpack …/hdparm_9.51+ds-1+deb9u1_armhf.deb …

Unpacking hdparm (9.51+ds-1+deb9u1) …

Selecting previously unselected package powermgmt-base.

Preparing to unpack …/powermgmt-base_1.31+nmu1_all.deb …

Unpacking powermgmt-base (1.31+nmu1) …

Setting up powermgmt-base (1.31+nmu1) …

Setting up hdparm (9.51+ds-1+deb9u1) …

Processing triggers for man-db ( …
root@raspberrypi:~# hdparm -r0 /dev/sda
  setting readonly to 0 (off)
  readonly      =  0 (off)

Now that I know the drive is writeable, I need to create the partition. I used


Navigate through the menu and select the maximum size
                                                                                        Disk: /dev/sda
Size: 58.2 GiB, 62495129600 bytes, 122060800 sectors
Label: dos, identifier: 0x00000000

Device Boot Start End Sectors Size Id Type
>> /dev/sda1 2048 122060799 122058752 58.2G 83 Linux

Once you see “Syncing disks.”, you can format the disk. I formatted the partition sda1 with ext4 (I may want to encrypt in the future). Unmount and then format.

root@raspberrypi:~# umount /dev/sda1
root@raspberrypi:~# mkfs.ext4 /dev/sda1
mke2fs 1.43.4 (31-Jan-2017)
Found a dos partition table in /dev/sda1
Proceed anyway? (y,N) y
Creating filesystem with 2828032 4k blocks and 707136 inodes
Filesystem UUID: 363f1b4a-b0f5-4c7b-bf91-66f3823032d6
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208

Allocating group tables: done
Writing inode tables: done
Creating journal (16384 blocks): done
Writing superblocks and filesystem accounting information: done


Make the backup directory, edit fstab and mount the directory.  Insert into fstab with your uuid “UUID=363f1b4a-b0f5-4c7b-bf91-66f3823032d6 /backups auto nosuid,nodev,nofail 0 0
”   The second to last avoids backup and the last one enables fsck on reboot.

root@raspberrypi:~# blkid 
/dev/mmcblk0p1: LABEL="boot" UUID="DDAB-3A15" TYPE="vfat" PARTUUID="b53687e8-01"
/dev/mmcblk0p2: LABEL="rootfs" UUID="5fa1ec37-3719-4b25-be14-1f7d29135a13" TYPE="ext4" PARTUUID="b53687e8-02"
/dev/mmcblk0: PTUUID="b53687e8" PTTYPE="dos"
/dev/sdb: UUID="363f1b4a-b0f5-4c7b-bf91-66f3823032d6" TYPE="ext4"
root@raspberrypi:~# mkdir /backups 
root@raspberrypi:~# vim /etc/fstab
root@raspberrypi:~# mount -a
root@raspberrypi:~# mount
UUID=363f1b4a-b0f5-4c7b-bf91-66f3823032d6 /backups auto nosuid,nodev,nofail 0 0

You should see backups listed. (Note: I bricked my Raspberry Pi with a bad FSTAB entry, and mounted it on my Mac using Paragon and removed the bad fstab entry. )

Update Crontab with daily backups.

crontab -e

Setup an editor for crontab.

root@raspberrypi:~# crontab -e
no crontab for root - using an empty one

Select an editor. To change later, run 'select-editor'.
1. /bin/ed
2. /bin/nano <---- easiest
3. /usr/bin/vim.basic
4. /usr/bin/vim.tiny

Choose 1-4 [2]: 3
crontab: installing new crontab

I added this line and copied it to /etc/cron.daily/

0 1 * * * /usr/bin/rsync -r /data/ /backups/`date +%w-%A`

crontab -l > pi-backup
mv /root/pi-backup /etc/cron.daily
run-parts /etc/cron.daily

Note, I had to add #!/bin/bash after I copied and remove the timing of the job.

Also, check to see if rsync is installed with which rsync and apt-get install rsync.

This enables backups on a daily basis rotating every 7 days.

Check back on the following day to see your backups

root@raspberrypi:~# /usr/bin/rsync -r /data/ /backups/`date +%w-%A`
root@raspberrypi:~# find /backups

Good luck, I hope this helps you with your Raspberry Pi.


Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.