go.d smartctl: do scan only once on startup if interval is 0 (#18144)

5 files changed, 13 insertions, 8 deletions

diff --git a/src/go/plugin/go.d/modules/smartctl/collect.go b/src/go/plugin/go.d/modules/smartctl/collect.go
index e8f8357d68..35585db62f 100644
--- a/src/go/plugin/go.d/modules/smartctl/collect.go
+++ b/src/go/plugin/go.d/modules/smartctl/collect.go
@@ -164,7 +164,7 @@ func (s *Smartctl) collectSmartDevice(mx map[string]int64, dev *smartDevice) {
 }
 
 func (s *Smartctl) isTimeToScan(now time.Time) bool {
-	return now.After(s.lastScanTime.Add(s.ScanEvery.Duration()))
+	return s.ScanEvery.Duration().Seconds() != 0 && now.After(s.lastScanTime.Add(s.ScanEvery.Duration()))
 }
 
 func (s *Smartctl) isTimeToPollDevices(now time.Time) bool {
diff --git a/src/go/plugin/go.d/modules/smartctl/config_schema.json b/src/go/plugin/go.d/modules/smartctl/config_schema.json
index e03f8081da..afe7ce1a9f 100644
--- a/src/go/plugin/go.d/modules/smartctl/config_schema.json
+++ b/src/go/plugin/go.d/modules/smartctl/config_schema.json
@@ -20,7 +20,7 @@
       },
       "scan_every": {
         "title": "Scan interval",
-        "description": "Interval for discovering new devices using `smartctl --scan`, measured in seconds.",
+        "description": "Interval for discovering new devices using `smartctl --scan`, measured in seconds. Set to 0 to scan devices only once on startup.",
         "type": "number",
         "minimum": 1,
         "default": 900
diff --git a/src/go/plugin/go.d/modules/smartctl/metadata.yaml b/src/go/plugin/go.d/modules/smartctl/metadata.yaml
index 0b54f69fbe..9293c25419 100644
--- a/src/go/plugin/go.d/modules/smartctl/metadata.yaml
+++ b/src/go/plugin/go.d/modules/smartctl/metadata.yaml
@@ -97,7 +97,7 @@ modules:
               default_value: 5
               required: false
             - name: scan_every
-              description: interval for discovering new devices using `smartctl --scan`, measured in seconds.
+              description: interval for discovering new devices using `smartctl --scan`, measured in seconds. Set to 0 to scan devices only once on startup.
               default_value: 900
               required: false
             - name: poll_devices_every
diff --git a/src/go/plugin/go.d/modules/smartctl/scan.go b/src/go/plugin/go.d/modules/smartctl/scan.go
index e4291be4f9..06c8cdcb7f 100644
--- a/src/go/plugin/go.d/modules/smartctl/scan.go
+++ b/src/go/plugin/go.d/modules/smartctl/scan.go
@@ -53,11 +53,15 @@ func (s *Smartctl) scanDevices() (map[string]*scanDevice, error) {
 			// Accurate device type information is crucial because we use the `--device` option to gather data.
 			// Using the wrong type can lead to issues.
 			// For example, using 'scsi' for 'sat' devices prevents `smartctl` from issuing the necessary ATA commands.
-			resp, _ := s.exec.deviceInfo(dev.name, dev.typ, s.NoCheckPowerMode)
-			if resp != nil && isExitStatusHasBit(resp, 2) {
-				correctType := "sat"
-				s.Debugf("changing device '%s' type '%s' -> '%s'", dev.name, dev.typ, correctType)
-				dev.typ = correctType
+			d := scanDevice{name: dev.name, typ: "sat"}
+			if _, ok := s.scannedDevices[d.key()]; ok {
+				dev.typ = "sat"
+			} else {
+				resp, _ := s.exec.deviceInfo(dev.name, dev.typ, s.NoCheckPowerMode)
+				if resp != nil && isExitStatusHasBit(resp, 2) {
+					s.Debugf("changing device '%s' type 'scsi' -> 'sat'", dev.name)
+					dev.typ = "sat"
+				}
 			}
 		}
 
diff --git a/src/go/plugin/go.d/modules/smartctl/smartctl.go b/src/go/plugin/go.d/modules/smartctl/smartctl.go
index 1ea1a8fbaf..0ba0491794 100644
--- a/src/go/plugin/go.d/modules/smartctl/smartctl.go
+++ b/src/go/plugin/go.d/modules/smartctl/smartctl.go
@@ -38,6 +38,7 @@ func New() *Smartctl {
 			DeviceSelector:   "*",
 		},
 		charts:      &module.Charts{},
+		forceScan:   true,
 		deviceSr:    matcher.TRUE(),
 		seenDevices: make(map[string]bool),
 	}