System migration to USB disk

I would like to migrate the OpenHAB system on a Raspberry Pi (3) to an external USB. I imagine that a USB stick would have the same degradation problems as an sdcard. Is a regular 2.5" SSD (which seem available in a minimum size of 120GB) the best solution?

I moved mine to a 240GB SD that I had from an old laptop.with a USB case. No hard drive issues (yet).

Thanks. How have you powered the SSD and interfaced to the Pi (data and power connections)?

I bought this.

The ‚Move Root to USB‘ script (openHAB-config) will enable 1A power delivery for USB. Normaly thats enough for a SSD + external enclosure. If not than you need an external power supply.
Keep in mind that your raspi needs enough power to run stable. The offical raspi power supply delivers enough power for raspi & external SSD, other power supplies might cheap out…

I suspect your question is another instance of the XY problem.
If you want to avoid SD wearout problems, have a look at ZRAM, part of openHABian.

Thanks, I did consider ZRAM. Looking through some earlier threads it should be OK provided a controlled shutdown is executed? Are there any other benefits to using ZRAM?

See this thread.
It’s compressing RAM, speeding up some of the applications. It’s for free, it’s standard HW etc much of which an SSD is not.

My SSD was both because it was an old laptop drive I already possessed.

It’s not standard to equip a RPi with an SSD. Non standard does not mean it does not work but that you are for the most part on your own should you run into trouble.

It is USB connected just like the SD card is.

The internal SD reader is not USB connected and it clearly requires a number of manual config steps to boot from anything that’s USB-connected so this is non standard in the sense I used that term above.

Thanks for your inputs. So it sounds like I should use ZRAM and set up a backup. Would a USB drive attached to a router (the Pi is connected to the router via a switch by Cat6) be OK to use as a target for the backup (this could be a USB stick or a SSD)? I have a NAS but it’s not always switched on. I plan to use the Amanda backup after reading through documentation on setting it up (please bear with me I’m on a learning curve here).

One other thing, I have a Pi B+ with 1GB memory and a new Pi 4 with 4GB. Before I get into too much development will the B+ be OK to run with going forward for OpenHAB/home automation? I had planned to use the Pi 4 for another project and also read somewhere it does not work well with the Aeotec Z-stick Gen 5 Z-wave controller.


The Pi 4 has a non-standard USB port issue that was not discovered until after release. The workaround for using that USB stick is to plug it into a USB hub connected to the Pi.

If you manage to mount that to the Pi running OH, yes.

A Pi 1 ? That I would not start with as it has just 1 lame CPU core. Any Pi 2 or newer is fine.

Raspberry Pi Model B Rev 2

I’m experiencing issues with access to the Github repository using 30 System Settings / 38 Use zram (BETA).

When I am asked for a username and password to access the repository, what should I enter please?

Create your own Github account

OK, thanks. That seems not the problem:

remote: Repository not found.
fatal: repository ‘’ not found
/opt/openhabian/functions/zram.bash: line 15: cd: /tmp/openhabian.AYv8ygDDfz: No such file or directory
/bin/sh: 0: Can’t open ./
Failed to start zram-config.service: Unit zram-config.service not found.

I’m using PuTTY on Windows 10 to access the Pi.

I am guessing @mstormi reorganized his repos.