diff --git a/entrypoint.sh b/entrypoint.sh
index c4ff3ae..3b01fff 100755
--- a/entrypoint.sh
+++ b/entrypoint.sh
@@ -32,7 +32,7 @@ if [ -n "$RCON_PASSWORD" ]; then
   echo "set sv_rconpassword $RCON_PASSWORD" >> /srv/server.cfg
 fi
 
-UPDATE_MASTER=${UPDATE_MASTER:-true}
+UPDATE_MASTER=${UPDATE_MASTER:-"true"}
 echo "set sv_updatemaster $UPDATE_MASTER" >> /srv/server.cfg
 
 # As of Zandrodum 3.0.0 we have to use `+addbot` instead using server.cfg