Add flag to avoid lock file

sorintlab · Feb 26, 2021 · 2d0b8e5 · 2d0b8e5
1 parent dabfce5
commit 2d0b8e5
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Showing 17 changed files with 44 additions and 34 deletions.
diff --git a/cmd/keeper/cmd/keeper.go b/cmd/keeper/cmd/keeper.go
@@ -115,6 +115,7 @@ type config struct {
 
 	canBeMaster             bool
 	canBeSynchronousReplica bool
+	disableDataDirLocking   bool
 }
 
 var cfg config
@@ -142,6 +143,7 @@ func init() {
 
 	CmdKeeper.PersistentFlags().BoolVar(&cfg.canBeMaster, "can-be-master", true, "prevent keeper from being elected as master")
 	CmdKeeper.PersistentFlags().BoolVar(&cfg.canBeSynchronousReplica, "can-be-synchronous-replica", true, "prevent keeper from being chosen as synchronous replica")
+	CmdKeeper.PersistentFlags().BoolVar(&cfg.disableDataDirLocking, "disable-data-dir-locking", false, "disable locking on data dir. Warning! It'll cause data corruptions if two keepers are concurrently running with the same data dir.")
 
 	if err := CmdKeeper.PersistentFlags().MarkDeprecated("id", "please use --uid"); err != nil {
 		log.Fatal(err)
@@ -2032,26 +2034,29 @@ func keeper(c *cobra.Command, args []string) {
 	// Open (and create if needed) the lock file.
 	// There is no need to clean up this file since we don't use the file as an actual lock. We get a lock
 	// on the file. So the lock get released when our process stops (or log.Fatalfs).
-	lockFileName := filepath.Join(cfg.dataDir, "lock")
-	lockFile, err := os.OpenFile(lockFileName, os.O_RDWR|os.O_CREATE, 0644)
-	if err != nil {
-		log.Fatalf("cannot take exclusive lock on data dir %q: %v", lockFileName, err)
-	}
+	var lockFile *os.File
+	if !cfg.disableDataDirLocking {
+		lockFileName := filepath.Join(cfg.dataDir, "lock")
+		lockFile, err = os.OpenFile(lockFileName, os.O_RDWR|os.O_CREATE, 0644)
+		if err != nil {
+			log.Fatalf("cannot take exclusive lock on data dir %q: %v", lockFileName, err)
+		}
 
-	// Get a lock on our lock file.
-	ft := &syscall.Flock_t{
-		Type:   syscall.F_WRLCK,
-		Whence: int16(io.SeekStart),
-		Start:  0,
-		Len:    0, // Entire file.
-	}
+		// Get a lock on our lock file.
+		ft := &syscall.Flock_t{
+			Type:   syscall.F_WRLCK,
+			Whence: int16(io.SeekStart),
+			Start:  0,
+			Len:    0, // Entire file.
+		}
 
-	err = syscall.FcntlFlock(lockFile.Fd(), syscall.F_SETLK, ft)
-	if err != nil {
-		log.Fatalf("cannot take exclusive lock on data dir %q: %v", lockFileName, err)
-	}
+		err = syscall.FcntlFlock(lockFile.Fd(), syscall.F_SETLK, ft)
+		if err != nil {
+			log.Fatalf("cannot take exclusive lock on data dir %q: %v", lockFileName, err)
+		}
 
-	log.Infow("exclusive lock on data dir taken")
+		log.Infow("exclusive lock on data dir taken")
+	}
 
 	if cfg.uid != "" {
 		if !pg.IsValidReplSlotName(cfg.uid) {
@@ -2084,5 +2089,7 @@ func keeper(c *cobra.Command, args []string) {
 
 	<-end
 
-	lockFile.Close()
+	if !cfg.disableDataDirLocking {
+		lockFile.Close()
+	}
 }
diff --git a/doc/commands/stolon-keeper.md b/doc/commands/stolon-keeper.md
@@ -13,8 +13,11 @@ stolon-keeper [flags]
 ### Options
 
 ```
+      --can-be-master                   prevent keeper from being elected as master (default true)
+      --can-be-synchronous-replica      prevent keeper from being chosen as synchronous replica (default true)
       --cluster-name string             cluster name
       --data-dir string                 data directory
+      --disable-data-dir-locking        disable locking on data dir. Warning! It'll cause data corruptions if two keepers are concurrently running with the same data dir.
   -h, --help                            help for stolon-keeper
       --kube-resource-kind string       the k8s resource kind to be used to store stolon clusterdata and do sentinel leader election (only "configmap" is currently supported)
       --log-color                       enable color in log output (default if attached to a terminal)
@@ -44,4 +47,4 @@ stolon-keeper [flags]
       --uid string                      keeper uid (must be unique in the cluster and can contain only lower-case letters, numbers and the underscore character). If not provided a random uid will be generated.
 ```
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolon-proxy.md b/doc/commands/stolon-proxy.md
@@ -35,4 +35,4 @@ stolon-proxy [flags]
       --tcp-keepalive-interval int      set tcp keepalive interval (seconds)
 ```
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolon-sentinel.md b/doc/commands/stolon-sentinel.md
@@ -30,4 +30,4 @@ stolon-sentinel [flags]
       --store-timeout duration          store request timeout (default 5s)
 ```
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl.md b/doc/commands/stolonctl.md
@@ -44,4 +44,4 @@ stolonctl [flags]
 * [stolonctl update](stolonctl_update.md)	 - Update a cluster specification
 * [stolonctl version](stolonctl_version.md)	 - Display the version
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl_clusterdata.md b/doc/commands/stolonctl_clusterdata.md
@@ -38,4 +38,4 @@ Manage current cluster data
 * [stolonctl clusterdata read](stolonctl_clusterdata_read.md)	 - Retrieve the current cluster data
 * [stolonctl clusterdata write](stolonctl_clusterdata_write.md)	 - Write cluster data
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl_clusterdata_read.md b/doc/commands/stolonctl_clusterdata_read.md
@@ -41,4 +41,4 @@ stolonctl clusterdata read [flags]
 
 * [stolonctl clusterdata](stolonctl_clusterdata.md)	 - Manage current cluster data
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl_clusterdata_write.md b/doc/commands/stolonctl_clusterdata_write.md
@@ -42,4 +42,4 @@ stolonctl clusterdata write [flags]
 
 * [stolonctl clusterdata](stolonctl_clusterdata.md)	 - Manage current cluster data
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl_failkeeper.md b/doc/commands/stolonctl_failkeeper.md
@@ -40,4 +40,4 @@ stolonctl failkeeper [keeper uid] [flags]
 
 * [stolonctl](stolonctl.md)	 - stolon command line client
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl_init.md b/doc/commands/stolonctl_init.md
@@ -42,4 +42,4 @@ stolonctl init [flags]
 
 * [stolonctl](stolonctl.md)	 - stolon command line client
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl_promote.md b/doc/commands/stolonctl_promote.md
@@ -41,4 +41,4 @@ stolonctl promote [flags]
 
 * [stolonctl](stolonctl.md)	 - stolon command line client
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl_register.md b/doc/commands/stolonctl_register.md
@@ -51,4 +51,4 @@ stolonctl register [flags]
 
 * [stolonctl](stolonctl.md)	 - stolon command line client
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl_removekeeper.md b/doc/commands/stolonctl_removekeeper.md
@@ -40,4 +40,4 @@ stolonctl removekeeper [keeper uid] [flags]
 
 * [stolonctl](stolonctl.md)	 - stolon command line client
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl_spec.md b/doc/commands/stolonctl_spec.md
@@ -41,4 +41,4 @@ stolonctl spec [flags]
 
 * [stolonctl](stolonctl.md)	 - stolon command line client
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl_status.md b/doc/commands/stolonctl_status.md
@@ -41,4 +41,4 @@ stolonctl status [flags]
 
 * [stolonctl](stolonctl.md)	 - stolon command line client
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl_update.md b/doc/commands/stolonctl_update.md
@@ -42,4 +42,4 @@ stolonctl update [flags]
 
 * [stolonctl](stolonctl.md)	 - stolon command line client
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021
diff --git a/doc/commands/stolonctl_version.md b/doc/commands/stolonctl_version.md
@@ -40,4 +40,4 @@ stolonctl version [flags]
 
 * [stolonctl](stolonctl.md)	 - stolon command line client
 
-###### Auto generated by spf13/cobra on 6-Mar-2020
+###### Auto generated by spf13/cobra on 24-Feb-2021