From 032c6e12c36b87c83a5c793b77e1e1d4fd3a7bfa Mon Sep 17 00:00:00 2001
From: Chengxiong Ruan <chengxiongruan@gmail.com>
Date: Wed, 12 Jul 2023 17:21:17 -0700
Subject: [PATCH] sql: stablize TestValidateMixedVersionElements test

Informs: #106612

Release note: None
---
 pkg/sql/schemachanger/sctest/cumulative.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pkg/sql/schemachanger/sctest/cumulative.go b/pkg/sql/schemachanger/sctest/cumulative.go
index 7ddfbbd18fc3..e6c25740d337 100644
--- a/pkg/sql/schemachanger/sctest/cumulative.go
+++ b/pkg/sql/schemachanger/sctest/cumulative.go
@@ -1709,6 +1709,10 @@ func ValidateMixedVersionElements(t *testing.T, path string, newCluster NewMixed
 						},
 					}, true /*down level*/)
 					tdb := sqlutils.MakeSQLRunner(db)
+					// Use shorter liveness heartbeat interval and longer liveness ttl to
+					// avoid errors caused by refused connections.
+					tdb.Exec(t, `SET CLUSTER SETTING server.sqlliveness.heartbeat = '1s'`)
+					tdb.Exec(t, `SET CLUSTER SETTING server.sqlliveness.ttl = '120s'`)
 
 					// Wait for the schema changer job to hit desired stage, pause the job,
 					// perform a cluster upgrade, and resume the job.