backup on a Pi without keyboard or monitor

Entropy1024 · 03-19-2018, 01:40 PM

I want to write a script in Bash that will automatically backup my RAW photos from an SD card to an external USB drive via a Raspberry Pi. I intend to use it when on holiday to backup photos without having to take my laptop with me.

What I'm attempting to do is power up the Pi, plug in my cameras SD card via a USB/SD card reader, then plug in a 320GB USB HD and then get the script to mount the SD card & HD then rsync files from the SD card to the HD.

I know how to mount both devices and do the rsync. However I'm unsure as how to get the Pi to correctly identify the SD card from the 320GB HD.

I guess that if I plug the SD card in first it will get mounted as sda1, then the second device, the HD, will mount as sda2? So I could cron a script to rsync from sda1 to sda2 every 5 mins. However this seems dangerous as it may copy in the wrong direction.

Is there a simple way to ensure it will always copy from the SD to the HD?

Man thanks for any help.

Entropy1024 · 03-19-2018, 02:08 PM

Quote:

Originally Posted by Entropy1024

I want to write a script in Bash that will automatically backup my RAW photos from an SD card to an external USB drive via a Raspberry Pi. I intend to use it when on holiday to backup photos without having to take my laptop with me.

What I'm attempting to do is power up the Pi, plug in my cameras SD card via a USB/SD card reader, then plug in a 320GB USB HD and then get the script to mount the SD card & HD then rsync files from the SD card to the HD.

I know how to mount both devices and do the rsync. However I'm unsure as how to get the Pi to correctly identify the SD card from the 320GB HD.

I guess that if I plug the SD card in first it will get mounted as sda1, then the second device, the HD, will mount as sda2? So I could cron a script to rsync from sda1 to sda2 every 5 mins. However this seems dangerous as it may copy in the wrong direction.

Is there a simple way to ensure it will always copy from the SD to the HD?

Man thanks for any help.

I found out that if I use the following:

Code:

lsblk -f -e 11 | grep EOS_DIGITAL

It returns

Code:

└─sda1      vfat   EOS_DIGITAL 1368-0838

So I can see that the Canon EOS_Digital SD card is on sda1. I now need to isolate that first part of the line. I thought I could awk the drive out of that line using:

Code:

lsblk -f -e 11 | grep EOS_DIGITAL | awk '{PRINT $1}'

However it returns nothing! Where am I going wrong?

yancek · 03-19-2018, 02:42 PM

Quote:

I guess that if I plug the SD card in first it will get mounted as sda1, then the second device, the HD, will mount as sda2?

No, the second "device" would be sdb or sdc or something else, depending upon how many devices are attached. The sda is the device and sda1 is the partition on the device.

Keith Hedger · 03-19-2018, 02:48 PM

use uuid's to identify the drives they dont change

schneidz · 03-19-2018, 02:55 PM

Code:

[schneidz@hyper womens-health-challenge]$ lsblk -f -e 11 | awk '/swap/ {print $1}'
└─sda6

michaelk · 03-19-2018, 03:22 PM

One autonomous method would be to plug the drives into the Pi before you power it up. An @boot cron job would check to see if the both the card reader and drive was plugged and then copy the files.

Code:

lsblk -f -e 11 | grep EOS_DIGITAL | awk '{PRINT $1}'

Maybe a typo but PRINT should be print.

Code:

lsblk -f -e 11 | grep EOS_DIGITAL | awk 'print $1}'

Entropy1024 · 03-19-2018, 03:25 PM

Quote:

Originally Posted by schneidz

Code:

[schneidz@hyper womens-health-challenge]$ lsblk -f -e 11 | awk '/swap/ {print $1}'
└─sda6

That still returns nothing for me. What does the swap do?

michaelk · 03-19-2018, 03:34 PM

awk will search for the string between the / /.

Code:

lsblk -l -f -e 11  awk '/EOS_DIGITAL/ {print $1}'