From 0afd03e5eb31d88155142241ae2fdaf35502cce5 Mon Sep 17 00:00:00 2001
From: Sveta Smirnova <sveta.smirnova@percona.com>
Date: Thu, 22 Jan 2026 19:29:40 +0300
Subject: [PATCH] PT-2220 - pt-heartbeat's --check-read-only option behaves
 strangely

- Created fix and test case
---
 bin/pt-heartbeat         |   4 +-
 t/pt-heartbeat/pt-2220.t | 123 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 125 insertions(+), 2 deletions(-)
 create mode 100644 t/pt-heartbeat/pt-2220.t

diff --git a/bin/pt-heartbeat b/bin/pt-heartbeat
index e178eeae..46461353 100755
--- a/bin/pt-heartbeat
+++ b/bin/pt-heartbeat
@@ -6793,8 +6793,8 @@ sub main {
 
 sub server_is_readonly {
    my ($dbh) = @_;
-   my ( $is_read_only ) = $dbh->selectrow_array(q{SELECT @@global.read_only});
-   if ( $is_read_only ) {
+   my ( $is_read_only, $is_super_read_only ) = $dbh->selectrow_array(q{SELECT @@global.read_only, @@global.super_read_only});
+   if ( $is_read_only and not $is_super_read_only ) {
       my ( $privs ) = eval { $dbh->selectrow_array(q{SHOW GRANTS}) };
       if ( $privs && $privs =~ /\b(?:ALL|SUPER)\b/ ) {
          $is_read_only = undef;
diff --git a/t/pt-heartbeat/pt-2220.t b/t/pt-heartbeat/pt-2220.t
new file mode 100644
index 00000000..c50bfb10
--- /dev/null
+++ b/t/pt-heartbeat/pt-2220.t
@@ -0,0 +1,123 @@
+#!/usr/bin/env perl
+
+BEGIN {
+   die "The PERCONA_TOOLKIT_BRANCH environment variable is not set.\n"
+      unless $ENV{PERCONA_TOOLKIT_BRANCH} && -d $ENV{PERCONA_TOOLKIT_BRANCH};
+   unshift @INC, "$ENV{PERCONA_TOOLKIT_BRANCH}/lib";
+};
+
+use strict;
+use warnings FATAL => 'all';
+use English qw(-no_match_vars);
+use Test::More;
+use Data::Dumper;
+
+use PerconaTest;
+use Sandbox;
+require "$trunk/bin/pt-heartbeat";
+
+my $dp  = new DSNParser(opts=>$dsn_opts);
+my $sb  = new Sandbox(basedir => '/tmp', DSNParser => $dp);
+my $dbh = $sb->get_dbh_for('source');
+
+if ( !$dbh ) {
+   plan skip_all => 'Cannot connect to sandbox source';
+}
+elsif ( $sandbox_version lt '8.0' ) {
+   plan skip_all => "Requires MySQL 8.0 or newer";
+}
+
+$sb->create_dbs($dbh, ['test']);
+
+my ($output, $exit_code);
+my $cnf       = '/tmp/12345/my.sandbox.cnf';
+my $cmd       = "$trunk/bin/pt-heartbeat -F $cnf ";
+
+$dbh->do('drop table if exists test.heartbeat');
+$dbh->do(q{CREATE TABLE test.heartbeat (
+             id int NOT NULL PRIMARY KEY,
+             ts datetime NOT NULL
+          ) ENGINE=MEMORY});
+$sb->wait_for_replicas;
+
+$sb->do_as_root('source', 'SET GLOBAL read_only=0, super_read_only=0');
+
+($output, $exit_code) = full_output(
+   sub { pt_heartbeat::main("F=$cnf,h=127.1,P=12345",
+      qw(-D test --check-read-only --update --utc --run-time=5)
+   ) },
+   stderr => 1,
+);
+
+is(
+   $exit_code,
+   0,
+   "pt-heartbeat exited with 0 with read_only=0, super_read_only=0"
+) or diag($exit_code);
+
+is(
+   $output,
+   '',
+   "Nothing printed with read_only=0, super_read_only=0"
+) or diag($output);
+
+$sb->do_as_root('source', 'SET GLOBAL read_only=1, super_read_only=0');
+
+($output, $exit_code) = full_output(
+   sub { pt_heartbeat::main("F=$cnf,h=127.1,P=12345",
+      qw(-D test --check-read-only --update --utc --run-time=5)
+   ) },
+   stderr => 1,
+);
+
+is(
+   $exit_code,
+   0,
+   "pt-heartbeat exited with 0 with read_only=1, super_read_only=0"
+) or diag($exit_code);
+
+is(
+   $output,
+   '',
+   "Nothing printed with read_only=1, super_read_only=0"
+) or diag($output);
+
+$sb->do_as_root('source', 'SET GLOBAL super_read_only=1');
+
+($output, $exit_code) = full_output(
+   sub { pt_heartbeat::main("F=$cnf,h=127.1,P=12345",
+      qw(-D test --check-read-only --update --utc --run-time=5)
+   ) },
+   stderr => 1,
+);
+
+is(
+   $exit_code,
+   0,
+   "pt-heartbeat exited with 0 with read_only=1, super_read_only=1"
+) or diag($exit_code);
+
+is(
+   $output,
+   '',
+   "Nothing printed with read_only=1, super_read_only=1"
+) or diag($output);
+
+unlike(
+   $output,
+   qr/The MySQL server is running with the --super-read-only option so it cannot execute this statement/,
+   "No error printed with read_only=1, super_read_only=1"
+) or diag($output);
+
+$sb->do_as_root('source', 'SET GLOBAL read_only=0, super_read_only=0');
+
+# #############################################################################
+# Done.
+# #############################################################################
+$sb->do_as_root('source', 'SET GLOBAL read_only=0, super_read_only=0');
+
+$sb->wipe_clean($dbh);
+ok($sb->ok(), "Sandbox servers") or BAIL_OUT(__FILE__ . " broke the sandbox");
+
+done_testing;
+exit;