diff --git a/concourse/scripts/pr.ent.bash b/concourse/scripts/pr.ent.bash
index ac5ff907c97..000a76555ca 100755
--- a/concourse/scripts/pr.ent.bash
+++ b/concourse/scripts/pr.ent.bash
@@ -228,7 +228,7 @@ mc rb ${minio_server_alias}/txlog-${bucket_name} --force
 set -e
 
 echo "running mono_main,mono_basic"
-./mtr --clean-txlog-bucket-restart --suite=mono_main,mono_basic --testcase-timeout=30 --bootstrap-defaults-file=$WORKSPACE/eloqsql_pr/concourse/scripts/mtr_bootstrap.cnf
+./mtr --clean-txlog-bucket-restart --suite=mono_main,mono_basic --testcase-timeout=30 --max-connect-retries=1000 --bootstrap-defaults-file=$WORKSPACE/eloqsql_pr/concourse/scripts/mtr_bootstrap.cnf
 
 # Clean up minio buckets
 echo "cleaning minio buckets"
diff --git a/data_substrate b/data_substrate
index 195439fa0cf..cdf9e929c4a 160000
--- a/data_substrate
+++ b/data_substrate
@@ -1 +1 @@
-Subproject commit 195439fa0cf60aa337b275ba85b13a0e05059f14
+Subproject commit cdf9e929c4a5a0f8bb308fb960bf58f52f10efab
diff --git a/mysql-test/mariadb-test-run.pl b/mysql-test/mariadb-test-run.pl
index 1f0fc55f885..cb3283d0be3 100755
--- a/mysql-test/mariadb-test-run.pl
+++ b/mysql-test/mariadb-test-run.pl
@@ -296,6 +296,7 @@ END
 our $opt_check_testcases= 1;
 my $opt_mark_progress;
 my $opt_max_connections;
+my $opt_max_connect_retries;
 our $opt_report_times= 0;
 
 my $opt_sleep;
@@ -1211,6 +1212,7 @@ sub command_line_setup {
              'stop-file=s'              => \$opt_stop_file,
              'stop-keep-alive=i'        => \$opt_stop_keep_alive,
 	     'max-connections=i'        => \$opt_max_connections,
+	     'max-connect-retries=i'    => \$opt_max_connect_retries,
 	     'report-times'             => \$opt_report_times,
 	     'result-file'              => \$opt_resfile,
 	     'stress=s'                 => \$opt_stress,
@@ -5644,6 +5646,10 @@ ($$$)
   mtr_add_arg($args, "--test-file=%s", "include/check-testcase.test");
   mtr_add_arg($args, "--verbose");
 
+  if ( $opt_max_connect_retries ) {
+    mtr_add_arg($args, "--max-connect-retries=%d", $opt_max_connect_retries);
+  }
+
   if ( $mode eq "before" )
   {
     mtr_add_arg($args, "--record");
@@ -5739,6 +5745,10 @@ ($)
     mtr_add_arg($args, "--max-connections=%d", $opt_max_connections);
   }
 
+  if ( $opt_max_connect_retries ) {
+    mtr_add_arg($args, "--max-connect-retries=%d", $opt_max_connect_retries);
+  }
+
   if ( $opt_embedded_server )
   {
 
@@ -6106,6 +6116,7 @@ ($)
   timediff              With --timestamp, also print time passed since
                         *previous* test started
   max-connections=N     Max number of open connection to server in mysqltest
+  max-connect-retries=N Max connection attempts in mysqltest (default 500)
   report-times          Report how much time has been spent on different
                         phases of test execution.
   stress=ARGS           Run stress test, providing options to