diff --git a/app/vminsert/netstorage/netstorage.go b/app/vminsert/netstorage/netstorage.go
index 9f32e4eea6..e2600f8be6 100644
--- a/app/vminsert/netstorage/netstorage.go
+++ b/app/vminsert/netstorage/netstorage.go
@@ -808,9 +808,22 @@ func (sn *storageNode) checkReadOnlyMode() {
 		atomic.StoreUint32(&sn.isReadOnly, 0)
 		return
 	}
-	if !errors.Is(err, errStorageReadOnly) {
-		logger.Errorf("cannot check storage readonly mode for -storageNode=%q: %s", sn.dialer.Addr(), err)
+	if errors.Is(err, errStorageReadOnly) {
+		// The storage remains in read-only mode
+		return
 	}
+
+	// There was an error when sending nil buf to the storage.
+	logger.Errorf("cannot check storage readonly mode for -storageNode=%q: %s", sn.dialer.Addr(), err)
+
+	// Mark the connection to the storage as broken.
+	if err = sn.bc.Close(); err != nil {
+		cannotCloseStorageNodeConnLogger.Warnf("cannot close connection to storageNode %q: %s", sn.dialer.Addr(), err)
+	}
+	sn.bc = nil
+	atomic.StoreUint32(&sn.broken, 1)
+	sn.brCond.Broadcast()
+	sn.connectionErrors.Inc()
 }
 
 var (
diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index 7c4568b423..bccb5bc868 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -15,6 +15,8 @@ The following tip changes can be tested by building VictoriaMetrics components f
 
 ## v1.87.x long-time support release (LTS)
 
+* BUGFIX: [vminsert](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html): properly close broken vmstorage connection during [read-only state](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html#readonly-mode) checks at `vmstorage`. Previously it wasn't properly closed, which prevents restoring `vmstorage` node from read-only mode. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4870).
+
 ## [v1.87.8](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.87.8)
 
 Released at 2023-09-01