Does Zram stop SDCard failure when using InfluxDB and Grafana

  • Platform information:
    • Hardware: Raspberry Pi 3B+ with POE
    • OS: Openhabian
    • Java Runtime Environment: Latest with Openhabian
    • openHAB version: 3.3

Just started looking at using Openhabian install. I’ve used InfluxDB and Grafana on a Raspberry Pi 3B+ in the past and suffered SDCard burnout after a couple of months of use with my IOT system. Currently running both on a standard desktop/hard disk with no further problems.

Openhabian comes with InfluxDB and Grafana included. Does the Zram use in Openhabian reduce the SDCard burnout problems with using InfluxDB/Grafana on a Raspberry Pi ?? I note using an SSD to run Openhabian is discouraged, this would be one solution to the SDCard burnout problem.

I don’t want to go down this route again if I’m just going to have the SDCard fail in a couple of months and have to rebuild the system again. Any user experience with Openhabian running InfluxDB/Grafana on a Raspberry Pi would be much appreciated.

Many thanks
PaulM

Fix:

Sd cards will always burn out. It’s just a question of when. Switch to a sata HDD/SSD. (The ssd is overkill though.)

You can run I+G on ZRAM but make sure you have enough memory 1G probably isn’t enough. IIRC the openhabian menu installs them on ZRAM by default but please check yourself.

Not exactly. It’s discouraged to migrate the system and boot off SSD but you can well use them for additional storage.

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Many thanks for the replies.

I knew there may be a problem with SDCard burnout and ran InfluxDB with the database moved onto a USB memory stick, but that didn’t seem to help, the SDCard still failed in a short time.

I have a 2Gb RPi4 I can use if openhabian does indeed install InfluxDB and Grafana to use the ZRAM. I’d still like to hear from anyone who has been running Influx and Grafana successfully this way for more than a couple of months before I try it please ?

Regards
PaulM

It is just my opinion and I know this is not really welcome here, but I am running OH on a SSD since more than 1,5 years without any troubles on my RPi4.

The SSD was from our server which was replaced after about 30.000 hours usage, I think it has about 120GB in size.
If you are good in maths you could calculate how much hours it has now :wink:

I checked the wear sometime ago but cannot remember the syntax.
No indication on any wear.

But thats is of course just my personal impression …

The issue isn’t that it can’t be done. The issue is that openHABian doesn’t support it. If you use openHABian, then move everything to an SSD, you are no longer running openHABian. And yet, most users who do this sort of thing want the same level of support as if they were running openHABian still.

If you want to deviate from openHABian, that’s fine. But you’ll have to support yourself. That’s the point. It’s not a technical reason.

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I never understood what the reason in reality is.
I always read it is not supported but no explanation why.

For me it was the best solution ever to avoid the wear out of the SD cards.
Especially on the RPi4 which offers it out of the box.

It’s as Rich says, just take the original, literal meaning of “supported” and you’ll get there:
it means there need to be people to spend their spare time to maintain, test and validate openHABian and to support people that have questions or problems.
And it’s out of the question that it’s their decision what they want to support.
There does not have to be a (written) explanation around for that.

That being said, there also is a technical rationale. Read on here:

The internal one or the stick ? USB sticks are the exact same tech as SD flash mem so this was to be expected. Read on here.
You have to be careful in moving as running databases will affect many areas of the system, e.g. system logging and swap space so you can still easily trash your internal SD that way.

It was the SDCard that failed, the USB memory was, and still is, fine.

I have a couple of 120Gb SSDs so I’m tempted to just bite the bullet and move openhabian to an RPi4 booting from an SSD and see how it goes. My main aim is to shut down my desktop servers and use Raspberry Pis simply to reduce the 24/7 power consumption. Every little helps as they say !!

Reading the article referred to above it states …

‘What openHABian offers today, i.e. the combo of ZRAM and SD mirroring, provides results superior to what you obtain from moving to an SSD, it’s cheaper and requires less efforts.’

What exactly is ‘SD mirroring’ ? I run several systems, e.g. XigmaNAS, that boot from a USB memory stick and run from a RAM Disk, like a ‘live linux’ OS does. Is that what is meant by ‘SD mirroring’, which would be better than moving to an SSD, and would avoid the SDCard burnout caused by Influx/Grafana, but obviously requires much more RAM.

PaulM

RTFM please.

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Sorry, my mistake, I didn’t realise it was referring to the backup process.

It isn’t.