# How to Monitor X questions

**URL:** <https://community.netdata.cloud/t/how-to-monitor-x-questions/3297>\
**Category:** Help\
**Created:** [September 19, 2022, 1:51pm UTC](https://community.netdata.cloud/t/how-to-monitor-x-questions/3297 "2022-09-19T13:51:57Z")\
**Posts on this page:** 9\
**Page:** 1

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**Author:** ![Christopher\_Akritid1](https://yyz1.discourse-cdn.com/flex029/user_avatar/community.netdata.cloud/christopher_akritid1/32/419_2.png) [@Christopher\_Akritid1](https://community.netdata.cloud/u/Christopher_Akritid1)\
**Post date:** [September 19, 2022, 1:51pm UTC](https://community.netdata.cloud/t/how-to-monitor-x-questions/3297/1 "2022-09-19T13:51:58Z")

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Received this from a user today and most questions are common enough to warrant a public answer:

Q: How to monitor and alert for endpoints e.g when no request is made to [http://localhost:1234](http://localhost:1234/), or if the address gets a 400 or 500 status error page.

A: With the [HTTP Check collector](https://learn.netdata.cloud/docs/agent/collectors/go.d.plugin/modules/httpcheck).

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Q: How to monitor for dns or urls e.g when a url [example.com](http://example.com/) does not serve its requested application.

A: With the [DNS Query Collector](https://learn.netdata.cloud/docs/agent/collectors/go.d.plugin/modules/dnsquery).

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Q: How to monitor for a running container to trigger alert when the container stops or dies

I don’t see us having anything really good in this area. I found how to [alert on specific virtual network interfaces](https://github.com/netdata/netdata/issues/1163#issuecomment-283031649), a suggestion to use `last_collected_sec` of any collector [here](https://community.netdata.cloud/t/alert-for-another-docker-container-crash/887), and a different though useful alert called [docker\_unhealthy\_containers](https://community.netdata.cloud/t/docker-unhealthy-containers/1975). The problem seems to be the proper detection of a crash, as opposed to a normal termination. The only suggestion to distinguish this I’ve seen is [here](https://community.netdata.cloud/t/alert-for-another-docker-container-crash/887/4). We will discuss what we can do with @ilyam8

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Q: How to monitor if a systemd service stops.

A: We now have a decent [systemd units collector](https://learn.netdata.cloud/docs/agent/collectors/go.d.plugin/modules/systemdunits), which I suggest configuring to specifically monitor each service you want. This used to produce problematic charts on the cloud, but thanks to @ilyam8 they are now easier to understand (still on the nightlies, it will be in the next stable version too). We already have alerts for the `failed` state and it’s easy to add more for the `inactive` state as well (copy / paste the entire list and change `$failed` to `$inactive` plus the names).

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**Author:** ![andrewm4894](https://yyz1.discourse-cdn.com/flex029/user_avatar/community.netdata.cloud/andrewm4894/32/125_2.png) [@andrewm4894](https://community.netdata.cloud/u/andrewm4894)\
**Post date:** [September 19, 2022, 7:05pm UTC](https://community.netdata.cloud/t/how-to-monitor-x-questions/3297/2 "2022-09-19T19:05:28Z")

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I wonder if we should build an FAQ page like this in the docs somewhere?

Or maybe search in here is enough but could be nice to have a list somewhere in learn maybe.

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**Author:** ![dare](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@dare](https://community.netdata.cloud/u/dare)\
**Post date:** [September 20, 2022, 10:19am UTC](https://community.netdata.cloud/t/how-to-monitor-x-questions/3297/3 "2022-09-20T10:19:43Z")

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Informative. Thank you.

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<div class="post-metadata">

**Author:** ![Christopher\_Akritid1](https://yyz1.discourse-cdn.com/flex029/user_avatar/community.netdata.cloud/christopher_akritid1/32/419_2.png) [@Christopher\_Akritid1](https://community.netdata.cloud/u/Christopher_Akritid1)\
**Post date:** [September 20, 2022, 1:01pm UTC](https://community.netdata.cloud/t/how-to-monitor-x-questions/3297/4 "2022-09-20T13:01:09Z")

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Q: How to monitor SSL certificate expirations

A: Via the [x509 certificate collector](https://learn.netdata.cloud/docs/agent/collectors/go.d.plugin/modules/x509check).

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<div class="post-metadata">

**Author:** ![dare](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@dare](https://community.netdata.cloud/u/dare)\
**Post date:** [September 21, 2022, 2:51am UTC](https://community.netdata.cloud/t/how-to-monitor-x-questions/3297/5 "2022-09-21T02:51:35Z")

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Hi @Christopher_Akritid1  
Thank you for this. Please, how do I see this in the dashboard after configuring from the collector in the machine. I have tried restarting the Netdata service (sudo systemctl restart netdata), but it still is not showing in any of the dashboard.

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<div class="post-metadata">

**Author:** ![Christopher\_Akritid1](https://yyz1.discourse-cdn.com/flex029/user_avatar/community.netdata.cloud/christopher_akritid1/32/419_2.png) [@Christopher\_Akritid1](https://community.netdata.cloud/u/Christopher_Akritid1)\
**Post date:** [September 21, 2022, 2:01pm UTC](https://community.netdata.cloud/t/how-to-monitor-x-questions/3297/6 "2022-09-21T14:01:24Z")

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If it’s not showing up after changing the config file for these standard collectors, it almost always means there’s an error with that configuration and we can look into that in a different thread. Depending on the type of error, you may see something useful in `/var/log/netdata/error.log`.

It generally helps to run the collector in debug mode, when you have issues, so you don’t restart netdata and wait. Instructions on how to debug are in every collector’s documentation page.

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<div class="post-metadata">

**Author:** ![dare](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@dare](https://community.netdata.cloud/u/dare)\
**Post date:** [September 23, 2022, 4:04pm UTC](https://community.netdata.cloud/t/how-to-monitor-x-questions/3297/7 "2022-09-23T16:04:56Z")

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Thanks. I have checked. Could not find nothing. But still not showing the dashboard.

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<div class="post-metadata">

**Author:** ![Christopher\_Akritid1](https://yyz1.discourse-cdn.com/flex029/user_avatar/community.netdata.cloud/christopher_akritid1/32/419_2.png) [@Christopher\_Akritid1](https://community.netdata.cloud/u/Christopher_Akritid1)\
**Post date:** [September 23, 2022, 6:49pm UTC](https://community.netdata.cloud/t/how-to-monitor-x-questions/3297/8 "2022-09-23T18:49:32Z")

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Please create a new discussion with the config and the output of the debug command.

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<div class="post-metadata">

**Author:** ![Christopher\_Akritid1](https://yyz1.discourse-cdn.com/flex029/user_avatar/community.netdata.cloud/christopher_akritid1/32/419_2.png) [@Christopher\_Akritid1](https://community.netdata.cloud/u/Christopher_Akritid1)\
**Post date:** [December 16, 2022, 10:30am UTC](https://community.netdata.cloud/t/how-to-monitor-x-questions/3297/9 "2022-12-16T10:30:17Z")

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How to be alerted when a node goes offline

In Netdata Cloud open your personal settings from the button on the bottom left. Under the tab “Notifications” select to receive “All alerts and unreachable” for the rooms that contain the nodes you want to be notified about. You will receive emails when the nodes in those rooms are disconnected from/reconnected to the cloud.

 ![image](https://canada1.discourse-cdn.com/flex029/uploads/netdata2/original/2X/a/a635537d68c8eb2052ce2bbf8b560d4f1a81c07b.png)
