l: add monitoring config

3 files changed, 390 insertions, 0 deletions

diff --git a/lass/2configs/monitoring/alert-rules.nix b/lass/2configs/monitoring/alert-rules.nix
new file mode 100644
index 00000000..eae2569f
--- /dev/null
+++ b/lass/2configs/monitoring/alert-rules.nix
@@ -0,0 +1,208 @@
+# inspiration from https://github.com/Mic92/dotfiles/blob/master/nixos/eva/modules/prometheus/alert-rules.nix
+{ lib }:
+
+lib.mapAttrsToList
+  (name: opts: {
+    alert = name;
+    expr = opts.condition;
+    for = opts.time or "2m";
+    labels = { };
+    annotations.description = opts.description;
+  })
+  ({
+    prometheus_too_many_restarts = {
+      condition = ''changes(process_start_time_seconds{job=~"prometheus|pushgateway|alertmanager|telegraf"}[15m]) > 2'';
+      description = "Prometheus has restarted more than twice in the last 15 minutes. It might be crashlooping.";
+    };
+
+    alert_manager_config_not_synced = {
+      condition = ''count(count_values("config_hash", alertmanager_config_hash)) > 1'';
+      description = "Configurations of AlertManager cluster instances are out of sync.";
+    };
+
+    prometheus_not_connected_to_alertmanager = {
+      condition = "prometheus_notifications_alertmanagers_discovered < 1";
+      description = "Prometheus cannot connect the alertmanager\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}";
+    };
+
+    prometheus_rule_evaluation_failures = {
+      condition = "increase(prometheus_rule_evaluation_failures_total[3m]) > 0";
+      description = "Prometheus encountered {{ $value }} rule evaluation failures, leading to potentially ignored alerts.\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}";
+    };
+
+    prometheus_template_expansion_failures = {
+      condition = "increase(prometheus_template_text_expansion_failures_total[3m]) > 0";
+      time = "0m";
+      description = "Prometheus encountered {{ $value }} template text expansion failures\n  VALUE = {{ $value }}\n  LABELS = {{ $labels }}";
+    };
+
+    promtail_request_errors = {
+      condition = ''100 * sum(rate(promtail_request_duration_seconds_count{status_code=~"5..|failed"}[1m])) by (namespace, job, route, instance) / sum(rate(promtail_request_duration_seconds_count[1m])) by (namespace, job, route, instance) > 10'';
+      time = "15m";
+      description = ''{{ $labels.job }} {{ $labels.route }} is experiencing {{ printf "%.2f" $value }}% errors.'';
+    };
+
+    promtail_file_lagging = {
+      condition = ''abs(promtail_file_bytes_total - promtail_read_bytes_total) > 1e6'';
+      time = "15m";
+      description = ''{{ $labels.instance }} {{ $labels.job }} {{ $labels.path }} has been lagging by more than 1MB for more than 15m.'';
+    };
+
+    filesystem_full_80percent = {
+      condition = ''disk_used_percent{mode!="ro"} >= 95'';
+      time = "10m";
+      description = "{{$labels.instance}} device {{$labels.device}} on {{$labels.path}} got less than 20% space left on its filesystem.";
+    };
+
+    filesystem_full_krebs = {
+      condition = ''disk_used_percent{mode!="ro", org="krebs"} >= 95'';
+      time = "10m";
+      description = "{{$labels.instance}} device {{$labels.device}} on {{$labels.path}} got less than 5% space left on its filesystem.";
+    };
+
+    filesystem_inodes_full = {
+      condition = ''disk_inodes_free / disk_inodes_total < 0.10'';
+      time = "10m";
+      description = "{{$labels.instance}} device {{$labels.device}} on {{$labels.path}} got less than 10% inodes left on its filesystem.";
+    };
+
+    daily_task_not_run = {
+      # give 6 hours grace period
+      condition = ''time() - task_last_run{state="ok",frequency="daily"} > (24 + 6) * 60 * 60'';
+      description = "{{$labels.host}}: {{$labels.name}} was not run in the last 24h";
+    };
+
+    daily_task_failed = {
+      condition = ''task_last_run{state="fail"}'';
+      description = "{{$labels.host}}: {{$labels.name}} failed to run";
+    };
+
+    swap_using_30percent = {
+      condition = "mem_swap_total - (mem_swap_cached + mem_swap_free) > mem_swap_total * 0.3";
+      time = "30m";
+      description = "{{$labels.host}} is using 30% of its swap space for at least 30 minutes.";
+    };
+
+    systemd_service_failed = {
+      condition = ''systemd_units_active_code{name!~"nixpkgs-update-.*.service"} == 3'';
+      description = "{{$labels.host}} failed to (re)start service {{$labels.name}}.";
+    };
+
+    service_not_running = {
+      condition = ''systemd_units_active_code{name=~"teamspeak3-server.service|tt-rss.service", sub!="running"}'';
+      description = "{{$labels.host}} should have a running {{$labels.name}}.";
+    };
+
+    nfs_export_not_present = {
+      condition = "nfs_export_present == 0";
+      time = "1h";
+      description = "{{$labels.host}} cannot reach nfs export [{{$labels.server}}]:{{$labels.path}}";
+    };
+
+    ram_using_90percent = {
+      condition = "mem_buffered + mem_free + mem_cached < mem_total * 0.1";
+      time = "1h";
+      description = "{{$labels.host}} is using at least 90% of its RAM for at least 1 hour.";
+    };
+    load15 = {
+      condition = ''system_load15 / system_n_cpus{org!="nix-community"} >= 2.0'';
+      time = "10m";
+      description = "{{$labels.host}} is running with load15 > 1 for at least 5 minutes: {{$value}}";
+    };
+    reboot = {
+      condition = "system_uptime < 300";
+      description = "{{$labels.host}} just rebooted.";
+    };
+    uptime = {
+      # too scared to upgrade matchbox
+      condition = ''system_uptime {host!~"^(matchbox|grandalf)$"} > 2592000'';
+      description = "Uptime monster: {{$labels.host}} has been up for more than 30 days.";
+    };
+    telegraf_down = {
+      condition = ''min(up{job=~"telegraf",type!='mobile'}) by (source, job, instance, org) == 0'';
+      time = "3m";
+      description = "{{$labels.instance}}: {{$labels.job}} telegraf exporter from {{$labels.source}} is down.";
+    };
+    ping = {
+      condition = "ping_result_code{type!='mobile'} != 0";
+      description = "{{$labels.url}}: ping from {{$labels.instance}} has failed!";
+    };
+    ping_high_latency = {
+      condition = "ping_average_response_ms{type!='mobile'} > 5000";
+      description = "{{$labels.instance}}: ping probe from {{$labels.source}} is encountering high latency!";
+    };
+    http = {
+      condition = "http_response_result_code != 0";
+      description = "{{$labels.server}} : http request failed from {{$labels.instance}}: {{$labels.result}}!";
+    };
+    http_match_failed = {
+      condition = "http_response_response_string_match == 0";
+      description = "{{$labels.server}} : http body not as expected; status code: {{$labels.status_code}}!";
+    };
+    dns_query = {
+      condition = "dns_query_result_code != 0";
+      description = "{{$labels.domain}} : could retrieve A record {{$labels.instance}} from server {{$labels.server}}: {{$labels.result}}!";
+    };
+    secure_dns_query = {
+      condition = "secure_dns_state != 0";
+      description = "{{$labels.domain}} : could retrieve A record {{$labels.instance}} from server {{$labels.server}}: {{$labels.result}} for protocol {{$labels.protocol}}!";
+    };
+    connection_failed = {
+      condition = "net_response_result_code != 0";
+      description = "{{$labels.server}}: connection to {{$labels.port}}({{$labels.protocol}}) failed from {{$labels.instance}}";
+    };
+    healthchecks = {
+      condition = "hc_check_up == 0";
+      description = "{{$labels.instance}}: healtcheck {{$labels.job}} fails!";
+    };
+    cert_expiry = {
+      condition = "x509_cert_expiry < 7*24*3600";
+      description = "{{$labels.instance}}: The TLS certificate from {{$labels.source}} will expire in less than 7 days: {{$value}}s";
+    };
+
+    postfix_queue_length = {
+      condition = "avg_over_time(postfix_queue_length[1h]) > 10";
+      description = "{{$labels.instance}}: postfix mail queue has undelivered {{$value}} items";
+    };
+
+    zfs_errors = {
+      condition = "zfs_arcstats_l2_io_error + zfs_dmu_tx_error + zfs_arcstats_l2_writes_error > 0";
+      description = "{{$labels.instance}} reports: {{$value}} ZFS IO errors.";
+    };
+
+    # ignore devices that disabled S.M.A.R.T (example if attached via USB)
+    smart_errors = {
+      condition = ''smart_device_health_ok{enabled!="Disabled"} != 1'';
+      description = "{{$labels.instance}}: S.M.A.R.T reports: {{$labels.device}} ({{$labels.model}}) has errors.";
+    };
+
+    oom_kills = {
+      condition = "increase(kernel_vmstat_oom_kill[5m]) > 0";
+      description = "{{$labels.instance}}: OOM kill detected";
+    };
+
+    unusual_disk_read_latency = {
+      condition = "rate(diskio_read_time[1m]) / rate(diskio_reads[1m]) > 0.1 and rate(diskio_reads[1m]) > 0";
+      description = "{{$labels.instance}}: Disk latency is growing (read operations > 100ms)\n";
+    };
+
+    unusual_disk_write_latency = {
+      condition = "rate(diskio_write_time[1m]) / rate(diskio_write[1m]) > 0.1 and rate(diskio_write[1m]) > 0";
+      description = "{{$labels.instance}}: Disk latency is growing (write operations > 100ms)\n";
+    };
+
+    host_memory_under_memory_pressure = {
+      condition = "rate(node_vmstat_pgmajfault[1m]) > 1000";
+      description = "{{$labels.instance}}: The node is under heavy memory pressure. High rate of major page faults: {{$value}}";
+    };
+
+    ext4_errors = {
+      condition = "ext4_errors_value > 0";
+      description = "{{$labels.instance}}: ext4 has reported {{$value}} I/O errors: check /sys/fs/ext4/*/errors_count";
+    };
+
+    alerts_silences_changed = {
+      condition = ''abs(delta(alertmanager_silences{state="active"}[1h])) >= 1'';
+      description = "alertmanager: number of active silences has changed: {{$value}}";
+    };
+  })
diff --git a/lass/2configs/monitoring/prometheus.nix b/lass/2configs/monitoring/prometheus.nix
new file mode 100644
index 00000000..ba32c62a
--- /dev/null
+++ b/lass/2configs/monitoring/prometheus.nix
@@ -0,0 +1,110 @@
+{ config, lib, pkgs, ... }:
+{
+  #prometheus
+  krebs.iptables = {
+    enable = true;
+    tables.filter.INPUT.rules = [
+      { predicate = "-i retiolum -p tcp --dport 80"; target = "ACCEPT"; } # nginx
+      # { predicate = "-i retiolum -p tcp --dport 3012"; target = "ACCEPT"; } # grafana
+      # { predicate = "-i retiolum -p tcp --dport 9093"; target = "ACCEPT"; } # alertmanager
+      # { predicate = "-i retiolum -p tcp --dport 9223"; target = "ACCEPT"; } # alertmanager
+    ];
+  };
+
+  services.nginx = {
+    enable = true;
+    virtualHosts = {
+      "prometheus.lass.r" = {
+        locations."/".proxyPass = "http://localhost:9090";
+      };
+      "alert.lass.r" = {
+        locations."/".proxyPass = "http://localhost:9093";
+      };
+      "grafana.lass.r" = {
+        locations."/".proxyPass = "http://localhost:3012";
+      };
+    };
+  };
+
+  services.grafana = {
+    enable = true;
+    addr = "0.0.0.0";
+    port = 3012;
+    auth.anonymous = {
+      enable = true;
+      org_role = "Admin";
+    };
+  };
+  services.prometheus = {
+    enable = true;
+    ruleFiles = [
+      (pkgs.writeText "prometheus-rules.yml" (builtins.toJSON {
+        groups = [{
+          name = "alerting-rules";
+          rules = import ./alert-rules.nix { inherit lib; };
+        }];
+      }))
+    ];
+    scrapeConfigs = [
+      {
+        job_name = "telegraf";
+        scrape_interval = "60s";
+        metrics_path = "/metrics";
+        static_configs = [
+          {
+            targets = [
+              "prism.r:9273"
+              "dishfire.r:9273"
+              "yellow.r:9273"
+            ];
+          }
+        ];
+      }
+    ];
+    alertmanagers = [
+      { scheme = "http";
+        path_prefix = "/";
+        static_configs = [ { targets = [ "localhost:9093" ]; } ];
+      }
+    ];
+    alertmanager = {
+      enable = true;
+      webExternalUrl = "https://alert.lass.r";
+      listenAddress = "[::1]";
+      configuration = {
+        global = {
+          # The smarthost and SMTP sender used for mail notifications.
+          smtp_smarthost = "localhost:587";
+          smtp_from = "alertmanager@alert.lass.r";
+          # smtp_auth_username = "alertmanager@thalheim.io";
+          # smtp_auth_password = "$SMTP_PASSWORD";
+        };
+        route = {
+          receiver = "default";
+          routes = [
+            {
+              group_by = [ "host" ];
+              group_wait = "30s";
+              group_interval = "2m";
+              repeat_interval = "2h";
+              receiver = "all";
+            }
+          ];
+        };
+        receivers = [
+          {
+            name = "all";
+            webhook_configs = [{
+              url = "http://127.0.0.1:9223/";
+              max_alerts = 5;
+            }];
+          }
+          {
+            name = "default";
+          }
+        ];
+      };
+    };
+  };
+
+}
diff --git a/lass/2configs/monitoring/telegraf.nix b/lass/2configs/monitoring/telegraf.nix
new file mode 100644
index 00000000..5258b87e
--- /dev/null
+++ b/lass/2configs/monitoring/telegraf.nix
@@ -0,0 +1,72 @@
+{ config, lib, pkgs, ... }:
+let
+  isVM = lib.any (mod: mod == "xen-blkfront" || mod == "virtio_console") config.boot.initrd.kernelModules;
+in {
+
+  krebs.iptables.tables.filter.INPUT.rules = [
+    { predicate = "-i retiolum -p tcp --dport 9273"; target = "ACCEPT"; }
+  ];
+
+  systemd.services.telegraf.path = [ pkgs.nvme-cli ];
+
+  services.telegraf = {
+    enable = true;
+    extraConfig = {
+      agent.interval = "60s";
+      inputs = {
+        http_response = [
+          { urls = [
+              "http://localhost:8080/about/health/"
+          ]; }
+        ];
+        prometheus.metric_version = 2;
+        kernel_vmstat = { };
+        # smart = lib.mkIf (!isVM) {
+        #   path = pkgs.writeShellScript "smartctl" ''
+        #     exec /run/wrappers/bin/sudo ${pkgs.smartmontools}/bin/smartctl "$@"
+        #   '';
+        # };
+        system = { };
+        mem = { };
+        file = [{
+          data_format = "influx";
+          file_tag = "name";
+          files = [ "/var/log/telegraf/*" ];
+        }] ++ lib.optional (lib.any (fs: fs == "ext4") config.boot.supportedFilesystems) {
+          name_override = "ext4_errors";
+          files = [ "/sys/fs/ext4/*/errors_count" ];
+          data_format = "value";
+        };
+        exec = lib.optionalAttrs (lib.any (fs: fs == "zfs") config.boot.supportedFilesystems) {
+          ## Commands array
+          commands = [
+            (pkgs.writeScript "zpool-health" ''
+              #!${pkgs.gawk}/bin/awk -f
+              BEGIN {
+                while ("${pkgs.zfs}/bin/zpool status" | getline) {
+                  if ($1 ~ /pool:/) { printf "zpool_status,name=%s ", $2 }
+                  if ($1 ~ /state:/) { printf " state=\"%s\",", $2 }
+                  if ($1 ~ /errors:/) {
+                    if (index($2, "No")) printf "errors=0i\n"; else printf "errors=%di\n", $2
+                  }
+                }
+              }
+            '')
+          ];
+          data_format = "influx";
+        };
+        systemd_units = { };
+        swap = { };
+        disk.tagdrop = {
+          fstype = [ "tmpfs" "ramfs" "devtmpfs" "devfs" "iso9660" "overlay" "aufs" "squashfs" ];
+          device = [ "rpc_pipefs" "lxcfs" "nsfs" "borgfs" ];
+        };
+        diskio = { };
+      };
+      outputs.prometheus_client = {
+        listen = ":9273";
+        metric_version = 2;
+      };
+    };
+  };
+}