diff --git a/server/etcdmain/config_test.go b/server/etcdmain/config_test.go
index dd46f2949310..2008ca76b7d4 100644
--- a/server/etcdmain/config_test.go
+++ b/server/etcdmain/config_test.go
@@ -733,9 +733,11 @@ func TestConfigFileDeprecatedOptions(t *testing.T) {
 			// Note: experimental-warning-unary-request-duration deprecation is handled
 			// through a separate mechanism in embed.Config
 			if tc.configFileYAML.ExperimentalWarningUnaryRequestDuration != 0 {
-				assert.Equal(t, cfg.ec.WarningUnaryRequestDuration,
+				assert.Equalf(t, cfg.ec.WarningUnaryRequestDuration,
 					tc.configFileYAML.ExperimentalWarningUnaryRequestDuration,
-					"experimental warning duration should match")
+					"experimental warning duration mismatch - expected: %v, got: %v",
+					tc.configFileYAML.ExperimentalWarningUnaryRequestDuration,
+					cfg.ec.WarningUnaryRequestDuration)
 			}
 		})
 	}