From b882d2b7c7b4262dcb41ee0d47a87ecd2a1c4f51 Mon Sep 17 00:00:00 2001
From: johncming <johncming@yahoo.com>
Date: Sat, 6 Nov 2021 17:41:06 +0800
Subject: [PATCH] tsdb/wal: Avoid writing closed channel. (#9566)

Signed-off-by: johncming <johncming@yahoo.com>
---
 tsdb/wal/wal.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tsdb/wal/wal.go b/tsdb/wal/wal.go
index 872e83a4d..b2d370914 100644
--- a/tsdb/wal/wal.go
+++ b/tsdb/wal/wal.go
@@ -472,6 +472,10 @@ func (w *WAL) NextSegment() error {
 
 // nextSegment creates the next segment and closes the previous one.
 func (w *WAL) nextSegment() error {
+	if w.closed {
+		return errors.New("wal is closed")
+	}
+
 	// Only flush the current page if it actually holds data.
 	if w.page.alloc > 0 {
 		if err := w.flushPage(true); err != nil {