Netdata Community

Questions about Reachability notifications and logging to disk

I am new to using Netdata. At the moment I only have it installed on a Raspberry Pi, after stumbling across a guide on installing it. I plan to learn more about it before installing it on cloud instances.

Are there continuous writes to the SD card from Netdata running on the RasPi, or is all data sent to the cloud?

If there are constant writes being made to the SD card, I would like to reduce this as much as possible or have the logging done in RAM and written to disk (SD card) occasionally (using something like log2ram).

Also, I keep in getting reachability notification, saying that the connection is lost and then a couple of minutes later saying that the connection has been re-established. Is it possible to have this only occur if the connection is lost for more than x seconds, so I don’t keep in getting them?

Is it normal for a home internet connection to have these issues? It is a 60/10 VDSL connection which is normally stable as far as I know.


The netdata default storage engine is memory mode = dbengine. With dbengine, disk writes are compressed, happen in batches of large sequential I/O requests that bypass the OS filesystem cache and are throttled so as to minimize interference with the system. Those writes are magnetic media friendly because they are large and sequential, and also NAND Flash friendly because there is minimal write amplification.

If you are not interested in keeping history on disk you can try using the memory exlusive storage engines, such as memory mode = ram.

I will let somebody else answer about the reachability notification.

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Hey @eggbean welcome to the forums!

Thanks @Markos_Fountoulakis for this little write-up on how our dbengine behaves in sdcards, I am sure it’s super interesting to. a lot of raspberry pi fans and IoT professionals.

@eggbean can you be a bit more specific about the reachability notification? How are you getting that notification? I think the speed for the connection stability is not the issue, since I am assuming that you are using WIFI, which can have weak signal depending on how the sender and the receiver are put in relation to the space around them.

Again, welcome to our community :slight_smile: Make sure to stick around!

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Thanks for the replies. I’m late in replying as I did not notice the notification email amongst the deluge of emails I am getting from netdata. I have had to disable audible notifications sounds on all my devices as it’s driving me nuts.

I am getting around 30 emails a day saying: is unreachable

Netdata Cloud is not able to reach the node

…alternating with ones saying that it is reachable again.

It has a wired connection to the router/switch. I’m not using wifi. I have no reason to believe that the RasPi is actually losing an internet connection. I have set a corn job to run a script every minute to email me if there are any ping failures, to check if there is anything strange going on.

How can I disable this alert, or preferably, only have it alert when there has been no connection for x minutes?

@eggbean we will soon ship alarm and reachability notifications via email.
Currently to disable these, you need to add a “key : value” pair “alarm-notifications-management : true” in your browser local storage.

For example in Chrome -> Developer Tools -> Application -> Local Storage -> Staging -> add a “key : value” pair “alarm-notifications-management : true”.

Then go to Profile/Notifications and set your personal email notification configuration as you wish . If you are an admin you can go to Manage Space/Notifications and disable email notifications for all users in the Space.

Hey Manos,

This doesn’t sound right. Is it a bug that we are aware that @eggbean is seeing a feature that we have yet to ship?

@eggbean sorry for this experience, it sounds really frustrating to receive so many unwarranted emails. We will get to the bottom of this. Thanks for your patience :v:

@OdysLam We shipped the feature too early by mistake and we rolled back now. The controls to manage the configuration in the UI remained under a feature flag. Now we rolled back and disabled email notifications for now. @eggbean apologies for the inconvenience

That’s a relief. But I tried updating the agent but I am still getting the emails. What do I need to do?

bash <(curl -Ss
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It hasn’t to do with the Agent, but with Netdata Cloud. I would expect that today you should stop receiving those emails, as we roll back the release.

I will ping the engineers to verify, cc @Leonidas_Vrachnis

Thanks for the patience @eggbean.

Okay thanks. The emails stopped arriving today. How come I seem to be the only person who got mailbombed?

@eggbean fyi we shipped the feature of alarm notifications via email. More notifications integrations will be delivered next year. Enjoy! and sorry for the inconvenience caused.