Domoticz

Hello the forum,
I have search the topics but could not find something convaincing.
Sorry if my request is not at the right place.
I am running domoticz latest release on a RPI3B and it's fine for the moment, but I would like to use this RPI for a new job.
Doing so, I would like to upgrade for a more powerfull model for domoticz.
5B is really too much in my opinion. I am more considering a 4B but I am a little bit lost regarding the model to choose between 1, 2, 4 ou 8 Gb.
My sensors are quite simple. I have some switches and relays, mostly on Dingtian boards (3 of them), a z-wave controler with some door sensors and power plug sockets, some temperature sensors. All this is growing slowly but surely.
Is the amount of RAM significant for domoticz and if yes, what is the minimum required ? Which model do you recommand ?
Second question, is there a topic describing the process to migrate from a 3B to a 4B ? Is a simple transfert of the SD card OK ?
Thanks for your replies.
Michel

You can check your current memory usage on your 3B using the Domoticz motherboard sensor hardware gateway. You will see Domoticz is not using a lot of memory.

You can buy whatever RPi 4. Better invest in a small SSD harddisk to prevent SD card wear and failures.

Just an SD card transfer will not work. You have to install a new OS on your new RPi. For transfer data the Domoticz database (file domotic.db) is important and will have all important data.

If you have external scripts running you also need to copy them over. The same for python plugins, they also need to be reinstalled on the new RPi. Dzvents, blocky, Lua scripts are normally stored in the database so no need to copy them.

Thanks waltervl for your answer.
I understand that any RPI4 will do the job. Although it is useless, I will probably opt for a mid-range, say a 4 GB, just for future recycling.
I know that running Domoticz on an SD card is not good in the long term (I had a bad experience last year with the complete loss of my piface cards). Since then, I take an .img of the card after each major change which allows me to quickly restore my Domoticz environment in case of a problem.
However, I am seriously thinking about equipping the RPI4 with a small SSD to improve the MTBF of my system.
Thanks for the summary description of the migration process. What about Docker and MQTT? Is it necessary to reinstall them or are they included in the database?

Docker and MQTT are not part of Domoticz so need to be installed again.

My experience:
I transferred to RPI4 and bookworm.
After the initial setup and copying the domoticz directory to a domoticz.bak directory I dus s Nee install of domoticz and to my surprise the new install used the 'old' domoticz.db.
So without inserting the old dB in the new directory everything worked like before.
I'm using heavy duty SD cards, about the same price as the usual. You have to order these from SanDisk.

Thanks to both of you.
OK for docker and MQTT, I had suspected it was necessary to reinstall them.
Althought the SD cards I have are of good quality, it reduces the risks but does not prevent against failure. That is why I do regular .img of all of them (I have an other Rasp running pi-hole) just to be able to create a new one on the go in case of breakdown.