blog.lazkani.io-20200902-historical/posts/monitoring/simple-cron-monitoring-with-healthchecks.org

#+BEGIN_COMMENT
.. title: Simple cron monitoring with HealthChecks
.. date: 2020-02-09
.. slug: simple-cron-monitoring-with-healthchecks
.. updated: 2020-02-09
.. status: published
.. tags: monitoring, healthchecks, cron
.. category: monitoring
.. authors: Elia el Lazkani
.. description: Ever needed to monitor simple things ? Well, HealthChecks seems perfect for that.
.. type: text
#+END_COMMENT

In a previous post entitled "{{% doc %}}automating-borg{{% /doc %}}", I showed you how you can automate your *borg* backups with *borgmatic*.

After I started using *borgmatic* for my backups and hooked it to a /cron/ running every 2 hours, I got interested into knowing what's happening to my backups at all times.

My experience comes handy in here, I know I need a monitoring system. I also know that traditional monitoring systems are too complex for my use case.

I need something simple. I need something I can deploy myself.

{{{TEASER_END}}}

* Choosing a monitoring system
I already know I don't want a traditional monitoring system like /nagios/ or /sensu/ or /prometheus/. It is not needed, it's an overkill.

I went through the list of hooks that *borgmatic* offers out of the box and checked each project.

I came across [[https://healthchecks.io/][HealthChecks]].

* HealthChecks
The [[https://healthchecks.io/][HealthChecks]] project works in a simple manner.
It simply offers syou an endpoint which you need to ping within a certain period, otherwise you get paged.

It has a lot of integrations from simple emails to other third party services that will call or message you or even trigger push notifications to your phone.

In my case, a simple email is enough. After all, they are simply backups and if they failed now, they will work when cron runs again in 2 hours.

* Deploy
Let's create a docker-compose service configuration that looks like the
following:

#+BEGIN_SRC yaml
healthchecks:
  container_name: healthchecks
  image: linuxserver/healthchecks:v1.12.0-ls48
  restart: unless-stopped
  ports:
    - "127.0.0.1:8000:8000"
  volumes:
    - "./healthchecks/data:/config"
  environment:
    PUID: "5000"
    PGID: "5000"
    SECRET_KEY: "super-secret-key"
    ALLOWED_HOSTS: '["*"]'
    DEBUG: "False"
    DEFAULT_FROM_EMAIL: "noreply@healthchecks.example.com"
    USE_PAYMENTS: "False"
    REGISTRATION_OPEN: "False"
    EMAIL_HOST: "smtp.example.com"
    EMAIL_PORT: "587"
    EMAIL_HOST_USER: "smtp@healthchecks.example.com"
    EMAIL_HOST_PASSWORD: "super-secret-password"
    EMAIL_USE_TLS: "True"
    SITE_ROOT: "https://healthchecks.example.com"
    SITE_NAME: "HealthChecks"
    MASTER_BADGE_LABEL: "HealthChecks"
    PING_ENDPOINT: "https://healthchecks.example.com/ping/"
    PING_EMAIL_DOMAIN: "healthchecks.example.com"
    TWILIO_ACCOUNT: "None"
    TWILIO_AUTH: "None"
    TWILIO_FROM: "None"
    PD_VENDOR_KEY: "None"
    TRELLO_APP_KEY: "None"
#+END_SRC

This will create a docker container exposing it locally on =127.0.0.1:8000=.
Let's point nginx to it and expose it using something similar to the following.

#+BEGIN_EXAMPLE
server {
    listen   443 ssl;
    server_name  healthchecks.example.com;

    ssl_certificate /path/to/the/fullchain.pem;
    ssl_certificate_key /path/to/the/privkey.pem;

    location / {
        proxy_pass http://127.0.0.1:8000;

        add_header X-Frame-Options SAMEORIGIN;
        add_header X-XSS-Protection "1; mode=block";
        proxy_redirect off;
        proxy_buffering off;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header X-Forwarded-Port $server_port;
        proxy_read_timeout 90;
    }

}
#+END_EXAMPLE

This should do nicely.

* Usage
Now it's a simple matter of creating a checks.


#+BEGIN_EXPORT html
<a class="reference" href="/images/simple-cron-monitoring-with-healthchecks/borgbackup-healthchecks.png" alt="HealthChecks monitoring for BorgBackup" algin="center">
<img src="/images/simple-cron-monitoring-with-healthchecks/borgbackup-healthchecks.thumbnail.png">
#+END_EXPORT
#+BEGIN_EXPORT html
</a>
#+END_EXPORT

This will give you a link that looks like the following

#+BEGIN_EXAMPLE
https://healthchecks.example.com/ping/84b2a834-02f5-524f-4c27-a2f24562b219
#+END_EXAMPLE

Let's feed it to *borgmatic*.

#+BEGIN_SRC yaml
hooks:
  healthchecks: https://healthchecks.example.com/ping/84b2a834-02f5-524f-4c27-a2f24562b219
#+END_SRC

After you configure the *borgmatic* hook to keep /HealthChecks/ in the know of what's going on.
We can take a look at the log to see what happened and when.

#+BEGIN_EXPORT html
<a class="reference" href="/images/simple-cron-monitoring-with-healthchecks/borgbackup-healthchecks-logs.png" alt="HealthChecks monitoring log for BorgBackup" algin="center">
<img src="/images/simple-cron-monitoring-with-healthchecks/borgbackup-healthchecks-logs.thumbnail.png">
#+END_EXPORT
#+BEGIN_EXPORT html
</a>
#+END_EXPORT


* Conclusion
As we saw in the blog post, now I am always in the know about my backups.
If my backup fails, I get an email to notify me of a failure.
I can also monitor how much time it takes my backups to run.
This is a very important feature for me to have.

The question of deploying one's own monitoring system is a personal choice.
After all, one can use free third party services if they would like.
The correct answer though is to always monitor.