diff --git a/.env.production.sample b/.env.production.sample
index e022a84059c3f2ee598d2317c2517cfb0af4732c..91fcce6ac4568bf1193ea56db6af9e54cc85d8b9 100644
--- a/.env.production.sample
+++ b/.env.production.sample
@@ -1,5 +1,6 @@
 # Service dependencies
 # You may set REDIS_URL instead for more advanced options
+# You may also set REDIS_NAMESPACE to share Redis between multiple Mastodon servers
 REDIS_HOST=redis
 REDIS_PORT=6379
 # You may set DATABASE_URL instead for more advanced options