Backport 1.6.3: replication: Don't write request coutners on DR Secon…

…dary nodes (#10936) (#10970)

* replication: Don't write request coutners on DR Secondary nodes (#10936)

* Add changelog

* Update 10970.txt

changelog/10970.txt

@@ -0,0 +1,4 @@
+```release-note:bug
+replication (enterprise): Don't write request count data on DR Secondaries.
+Fixes DR Secondaries becoming out of sync approximately every 30s.
+```

vault/core_metrics.go

@@ -15,8 +15,18 @@ import (
 
 func (c *Core) metricsLoop(stopCh chan struct{}) {
 	emitTimer := time.Tick(time.Second)
-	writeTimer := time.Tick(c.counters.syncInterval)
+
 	identityCountTimer := time.Tick(time.Minute * 10)
+	// Only emit on active node of cluster that is not a DR cecondary.
+	if standby, _ := c.Standby(); standby || c.IsDRSecondary() {
+		identityCountTimer = nil
+	}
+
+	writeTimer := time.Tick(c.counters.syncInterval)
+	// Do not process the writeTimer on DR Secondary nodes
+	if c.IsDRSecondary() {
+		writeTimer = nil
+	}
 
 	// This loop covers
 	// vault.expire.num_leases
@@ -68,11 +78,6 @@ func (c *Core) metricsLoop(stopCh chan struct{}) {
 			}
 			c.stateLock.RUnlock()
 		case <-identityCountTimer:
-			// Only emit on active node of cluster that is not a DR cecondary.
-			if standby, _ := c.Standby(); standby || c.IsDRSecondary() {
-				break
-			}
-
 			// TODO: this can be replaced by the identity gauge counter; we need to
 			// sum across all namespaces.
 			go func() {