OH3 Basic installation / external SD Card not recordnized

I’m running since several years now OH on my PI system.
Meanwhile on version 3.3 stable.
So far I was cloning every time the SDCard external, with the need to shutdown the system.
Now I shaw, that it is possible to due an external backup direct on a connect SD Reader with an addtional SD card.
But it seems the that the external SD Card is not recordniced from the system.

With: sudo fdisk -l
I only get this;

Device Boot Start End Sectors Size Id Type
/dev/mmcblk0p1 8192 532479 524288 256M c W95 FAT32 (LBA)
/dev/mmcblk0p2 532480 31116287 30583808 14.6G 83 Linux

with: dmesg
I get this
[ 4.217836] usb 1-1.2: New USB device found, idVendor=8564, idProduct=4000, bcdDevice= 0.37
[ 4.220888] usb 1-1.2: New USB device strings: Mfr=3, Product=4, SerialNumber=5
[ 4.222447] usb 1-1.2: Product: Transcend
[ 4.223943] usb 1-1.2: Manufacturer: TS-RDF5
[ 4.225441] usb 1-1.2: SerialNumber: 000000000039
[ 4.227916] usb-storage 1-1.2:1.0: USB Mass Storage device detected
[ 4.230551] scsi host0: usb-storage 1-1.2:1.0
[ 4.282036] systemd[1]: Set hostname to .
[ 4.784458] usb 1-1.1.1: new high-speed USB device number 5 using dwc_otg
[ 4.914953] usb 1-1.1.1: New USB device found, idVendor=0424, idProduct=7800, bcdDevice= 3.00
[ 4.917823] usb 1-1.1.1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[ 5.185170] systemd[1]: /lib/systemd/system/nmbd.service:9: PIDFile= references path below legacy directory /var/run/, updating /var/run/samba/nmbd.pid → /run/samba/nmbd.pid; please update the unit file accordingly.

Which show me, that Cardreader itself is there…

Any idea for me?

It is not strictly an OH question, but you may use “sudo lsblk” before and after inserting a SDcard. It will show you the device name even if there is no partiion defined on the card:

sudo lsblk
sda      8:0    0 223,6G  0 disk 
├─sda1   8:1    0   256M  0 part /boot
└─sda2   8:2    0 223,3G  0 part /
sdc      8:32   1  14,9G  0 disk 

“sdc” in my example is an empty SDcard. You will notice that there is no information about a mount point at the end of the entry, whereas sda1 and sda2 as partition entries have this information.

I suspect that existing partitions on the external SDcard would be mounted in /run/media/, but I did not test that.

Thanks Stefan for the answer.

Here are the screenshort from the different status:

  • PI without USB Reader inserted:
mmcblk0     179:0    0 29.7G  0 disk
├─mmcblk0p1 179:1    0  256M  0 part /boot
└─mmcblk0p2 179:2    0 14.6G  0 part /

With USB Reader inserted, and without SD Card inserted:

mmcblk0     179:0    0 29.7G  0 disk
├─mmcblk0p1 179:1    0  256M  0 part /boot
└─mmcblk0p2 179:2    0 14.6G  0 part /

Final, With USB Reader inserted, and with SD Card inserted:

mmcblk0     179:0    0 29.7G  0 disk
├─mmcblk0p1 179:1    0  256M  0 part /boot
└─mmcblk0p2 179:2    0 14.6G  0 part /

The SD card itself what is used, is 1:1 clone from the “internal” SD Card"

So far…


When the USB Reader is inserted/plugged in it will NOT show with lsblk as this command only shows the status of block devices (=media).
When the SDcard is inserted into the USB Reader and you do not see additional output I see two reasons:

  1. The USB reader is incompatible with the SD card (e.g. it cannot handle a SD card with the capacity you use, check the documentation of the USB reader for this).
  2. The cloning of the SD card was unsuccessfull and there are no partitions on the cloned SD card.

In both cases I recommend to plug the USB reader into another computer and check if the partitions on the SD card are shown with this USB reader.

Thanks for the Tipp Stefan,

but this I have alread testet before with two other SD CARD Reader.
Also the SDCARD itself is nicely booting when I put the into the internal SD Card Slot in the Pi.

Any other ideas? Have you done any thing in the e.g. /etc/fstab or etc to add the USB Reader? Is there an additional package needed für USB SD CARD usage, which is not be default in the OH3.3 Imaage installation?


Hi Jochen,

I did nothing to make my card reader do what it should do. No additional packages were installed, no configuration was added or amended.

My answers are based on a standard Raspberry Pi OS, whereas your statement

lets me assume your OS might be OpenHABian? If so, I cannot really help as I do not use openHABian myself and have no knowledge how the OS part has been amended by the openHABian maintainers. Your best way forward may be an additional tag “openhabian” for this thread so someone with the needed expertise can have a look.

Thanks Stefan.
I have added all the tags.

Has someone an idea?