common/headless: basic monitoring on by default

1 files changed, 40 insertions, 0 deletions

diff --git a/common/monitoring.nix b/common/monitoring.nix
new file mode 100644
index 0000000..e5f111c
--- /dev/null
+++ b/common/monitoring.nix
@@ -0,0 +1,40 @@
+{ config, lib, pkgs, ... }:
+
+{
+  # includes mail address, which includes ntfy token
+  sops.secrets."monit/mail".sopsFile = ../secrets/common.yaml;
+
+  services.monit = {
+    enable = true;
+
+    config = ''
+      include /run/secrets/monit/mail
+
+      set daemon 120 with start delay 60
+      set mailserver
+          ping.stuebinm.eu
+          port 2525
+
+      set httpd port 2812 address localhost
+          allow localhost
+
+      check filesystem root with path /
+            if space usage > 80% then alert
+            if inode usage > 80% then alert
+
+      check process sshd with pidfile /var/run/sshd.pid
+            start program  "${pkgs.systemd}/bin/systemctl start sshd"
+            stop program  "${pkgs.systemd}/bin/systemctl stop sshd"
+            if failed port 22 protocol ssh for 2 cycles then restart
+
+      check program is-system-running path ${pkgs.systemd}/bin/systemctl is-system-running
+            if status != 0 then alert
+
+      set mail-format {
+        subject: ${config.networking.hostName}/$SERVICE: $EVENT
+        message: Action: $ACTION $SERVICE: $DESCRIPTION.
+      ($DATE)
+      }
+    '';
+  };
+}