bicep: set up mysql/mariadb

hosts/bicep/configuration.nix

@@ -6,6 +6,7 @@
     ../../base.nix
     ./services/nginx
 
+    ./services/mysql.nix
     ./services/postgres.nix
 
     ./services/matrix

hosts/bicep/services/mysql.nix

@@ -0,0 +1,19 @@
+{ pkgs, config, ... }:
+{
+  services.mysql = {
+    enable = true;
+    dataDir = "/data/mysql";
+    package = pkgs.mariadb;
+    settings = {
+      mysqld = {
+        # PVV allows a lot of connections at the same time
+        max_connect_errors = 10000;
+      };
+    };
+  };
+
+  services.mysqlBackup = {
+    enable = true;
+    location = "/var/lib/mysql/backups";
+  };
+}