content: uptime monitoring

src/content/blog/hosting-comments-on-github-for-static-websites.md

@@ -16,7 +16,7 @@ description: >
 ## 2022 Update
 
 It has been a long time since I written this post and while I was remaking my
-website with a new stack I have been looking at what's available today. Many
+website with a new stack, I have been looking at what's available today. Many
 people had similar ideas with some clever solutions.
 
 <mark>[Giscus](https://giscus.app/) is the one that caught my eye and it's what

src/content/blog/uptime-monitoring-for-openwrt-and-unraid-cron.md

@@ -0,0 +1,81 @@
+---
+issue: 15
+
+author: Daniele Salvagni
+title: 'Uptime monitoring for OpenWrt and Unraid'
+pubDate: 'Nov 13, 2024'
+emoji: 🤖
+
+description: >
+  Using Uptime Kuma with Push URL to monitor the uptime of the internet
+  connectivity of OpenWrt routers and Unraid systems.
+---
+
+I have been using [Uptime Kuma](https://github.com/louislam/uptime-kuma) for
+quite some to monitor some services, and I wanted to add the following health
+checks:
+
+- Internet connectivity for some isolated networks (with OpenWrt routers)
+- Uptime of my Unraid server
+
+I tend to use Push monitoring whenever I can, as it doesn't need to accept
+ingress connections for private networks, and it does involve less moving parts.
+The easiest way would be to setup a simple **cron** on both systems.
+
+## OpenWrt Push Monitor
+
+You will need **ssh** access to your OpenWrt router. If you don't, you should
+generate a new key pair with the command:
+
+```sh
+ssh-keygen -t rsa
+```
+
+You can then set your public key through your router's
+[LuCI](https://openwrt.org/docs/guide-user/luci/start) web interface, by
+appending its content in _System → Administration_.
+
+You will then be able to ssh as root using:
+
+```sh
+ssh -oHostKeyAlgorithms=+ssh-rsa -i '<public_key_path>' root@<router_ip>
+```
+
+With that out of the way, let's add a simple `cron` to call our Push URL every
+minute. To edit your crontab, run `crontab -e` and then add the following line:
+
+```sh
+* * * * * wget --spider "https://<your_push_url>" >/dev/null 2>&1*
+```
+
+There should be a EOL character on the last line of the crontab file, just leave
+an empty line at the end to be sure. Now restart the cron service in order for
+the changes to take effect:
+
+```sh
+service cron restart
+```
+
+This will keep calling the Push URL every minute.
+
+## Unraid Push Monitor
+
+Adding a push monitor to Unraid is similar, but we will use a plugin instead of
+the command line, otherwise any changes won't be persisted between reboots.
+
+1. Install the
+   [CA Uer Scripts](https://forums.unraid.net/topic/48286-plugin-ca-user-scripts/)
+   plugin if you haven't already
+2. Go to _Settings → User Scripts → Add New Script_
+3. Edit the script by adding
+   `wget --spider "https://<your_push_url>" >/dev/null 2>&1*`
+4. Set the schedule as _Custom_, and type `* * * * *` to call the URL every
+   minute
+
+## Bonus: Other devices
+
+I also wanted to monitor internet connectivity on a router which doesn't support
+OpenWRT. In this case, I opted for a simple sketch I put together on a M5Atom
+ESP32 device which connects to the Wi-Fi network and repeatedly call the Push
+URL, and as the modem has an USB port, I am powering the ESP32 directly from
+there.