[SOLVED] Persistence lose all data after restart

[AnnaM (Anna)]

Dear Community, I am using a fresh installation of OpenHabian (3.0.0) on my Raspberry Pi 2 Model B.
First of all I used the default persistence to build up a chart. This is working fine until I restart the raspberry. After the restart my chart is empty.

Then I decideed to migrate my old rrd4j.persist file which worked in OH2. Also with this config my chart is working but only unfortentally until the restart. What is wrong with my configuration? Could anybody help me?

This is my current config:

Strategies 
{
   everyMinute	: "0 * * * * ?"
   //everyHour    : "0 0 * * * ?"
   //everyDay     : "0 0 0 * * ?"
   default = everyChange
}

Items {
       DHT22_Temperature, DHT22_Humidity : strategy = everyMinute, everyChange
}

[rlkoshak (Rich Koshak)]

Do you have zram active and enabled?

[AnnaM (Anna)]

Hi Rich,

thank you for your answer.
Oh, okay: zram is enabled by default in the new version of openhabian. I din’t know that. But how can I persist all values after a restart or a power cut or failure?

ZRAM status

This article is to track and document the current status of the ZRAM feature in openHABian. I’ll update it if there’s significant news. What is ZRAM and how does it work ? The ZRAM config utility for swap, directory & log is an OS enhancement for IoT / maker projects for reducing SD, NAND and eMMC block wear caused by write operations such as logging and persistence in openHAB. It uses compression to minimise precious memory footprint and extremely infrequent write outs and near RAM speed wor…

In this thread they are talking about Amanda to save the persistance files. How can I do that and is it the right way to do?

ZRAM status

Yes but that’ll stop OH so I would avoid that, too. Combine ZRAM with backup (Amanda in openHABian) to save the files on ZRAM of interest (persistence), the rest is irrelevant so no real loss when you lose them. No, OH cache is no longer on ZRAM (presuming you use a recent definition of ZRAM dirs in ztab, see openHABian config).

[MOS]

i sloved this for me, with disable and enable the zram in openhabian-config.

[rlkoshak (Rich Koshak)]

I can’t tell you the right way to go o what to change. Amanda is the backups service that comes with openHABian so I’m sure you should be able to follow the documentation on openHABian to install and configure it. You could disable ZRAM but you’ll lose the benefits that provdes. You might be able to use symbolic links to move the rrd4j files outside of zram but I don’t know if that will work with zram.

Any advice from Markus is going to trump anything I have to say on the matter.

[AnnaM (Anna)]

After I deactivated ZRAM and activated it again, it now works without any problems. According to Markus Storm, some bugs were probably responsible for the error, which have now been fixed afterwards.