MDEV-24097: galera[_3nodes] suite tests in MTR sporadically fails

This is the first part of the fixes for MDEV-24097. This commit contains the fixes for instability when testing Galera and when restarting nodes quickly: 1) Protection against a "stuck" old SST process during the execution of the new SST (after restarting the node) is now implemented for mariabackup / xtrabackup, which should help to avoid almost all conflicts due to the use of the same ports - both during testing with mtr, so and when restarting nodes quickly in a production environment. 2) Added more protection to scripts against unexpected return of the rc != 0 (in the commands for deleting temporary files, etc). 3) Added protection against unexpected crashes during binlog transfer (in SST scripts for rsync). 4) Spaces and some special characters in binlog filenames shouldn't be a problem now (at the script level). 5) Daemon process termination tracking has been made more robust against crashes due to unexpected termination of the previous SST process while new scripts are running. 6) Reading ssl encryption parameters has been moved from specific SST scripts to a common wsrep_sst_common.sh script, which allows unified error handling, unified diagnostics and simplifies script revisions in the future. 7) Improved diagnostics of errors related to the use of openssl. 8) Corrections have been made for xtrabackup-v2 (both in tests and in the script code) that restore the work of xtrabackup with updated versions of innodb. 9) Fixed some tests for galera_3nodes, although the complete solution for the problem of starting three nodes at the same time on fast machines will be done in a separate commit. No additional tests are required as this commit fixes problems with existing tests.

MDEV-24097: galera[_3nodes] suite tests in MTR sporadically fails
This is the first part of the fixes for MDEV-24097. This commit contains the fixes for instability when testing Galera and when restarting nodes quickly: 1) Protection against a "stuck" old SST process during the execution of the new SST (after restarting the node) is now implemented for mariabackup / xtrabackup, which should help to avoid almost all conflicts due to the use of the same ports - both during testing with mtr, so and when restarting nodes quickly in a production environment. 2) Added more protection to scripts against unexpected return of the rc != 0 (in the commands for deleting temporary files, etc). 3) Added protection against unexpected crashes during binlog transfer (in SST scripts for rsync). 4) Spaces and some special characters in binlog filenames shouldn't be a problem now (at the script level). 5) Daemon process termination tracking has been made more robust against crashes due to unexpected termination of the previous SST process while new scripts are running. 6) Reading ssl encryption parameters has been moved from specific SST scripts to a common wsrep_sst_common.sh script, which allows unified error handling, unified diagnostics and simplifies script revisions in the future. 7) Improved diagnostics of errors related to the use of openssl. 8) Corrections have been made for xtrabackup-v2 (both in tests and in the script code) that restore the work of xtrabackup with updated versions of innodb. 9) Fixed some tests for galera_3nodes, although the complete solution for the problem of starting three nodes at the same time on fast machines will be done in a separate commit. No additional tests are required as this commit fixes problems with existing tests.
b5cbe506 · Julius Goryavsky · 12087d67 · b5cbe506 · b5cbe506 · b5cbe506
Commit b5cbe506 authored Dec 23, 2021 by Julius Goryavsky
14 changed files
--- a/mysql-test/suite/galera/disabled.def
+++ b/mysql-test/suite/galera/disabled.def
@@ -28,5 +28,3 @@ query_cache: MDEV-15805 Test failure on galera.query_cache
 versioning_trx_id: MDEV-18590: galera.versioning_trx_id: Test failure: mysqltest: Result content mismatch
 galera_wsrep_provider_unset_set: wsrep_provider is read-only for security reasons
 pxc-421: wsrep_provider is read-only for security reasons
-galera_sst_xtrabackup-v2: Test fails due to innodb issues
-galera_sst_xtrabackup-v2_data_dir: Test fails due to innodb issues
--- a/mysql-test/suite/galera/r/galera_sst_xtrabackup-v2_data_dir.result
+++ b/mysql-test/suite/galera/r/galera_sst_xtrabackup-v2_data_dir.result
+connection node_1;
+connection node_2;
 Performing State Transfer on a server that has been shut down cleanly and restarted
+connection node_1;
 CREATE TABLE t1 (f1 CHAR(255)) ENGINE=InnoDB;
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
@@ -8,6 +11,7 @@ INSERT INTO t1 VALUES ('node1_committed_before');
 INSERT INTO t1 VALUES ('node1_committed_before');
 INSERT INTO t1 VALUES ('node1_committed_before');
 COMMIT;
+connection node_2;
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
 INSERT INTO t1 VALUES ('node2_committed_before');
@@ -17,6 +21,7 @@ INSERT INTO t1 VALUES ('node2_committed_before');
 INSERT INTO t1 VALUES ('node2_committed_before');
 COMMIT;
 Shutting down server ...
+connection node_1;
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
 INSERT INTO t1 VALUES ('node1_committed_during');
@@ -31,6 +36,7 @@ INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
+connect node_1a_galera_st_shutdown_slave, 127.0.0.1, root, , test, $NODE_MYPORT_1;
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
@@ -38,6 +44,7 @@ INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
+connection node_2;
 Starting server ...
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
@@ -47,6 +54,7 @@ INSERT INTO t1 VALUES ('node2_committed_after');
 INSERT INTO t1 VALUES ('node2_committed_after');
 INSERT INTO t1 VALUES ('node2_committed_after');
 COMMIT;
+connection node_1;
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
@@ -61,6 +69,7 @@ INSERT INTO t1 VALUES ('node1_committed_after');
 INSERT INTO t1 VALUES ('node1_committed_after');
 INSERT INTO t1 VALUES ('node1_committed_after');
 COMMIT;
+connection node_1a_galera_st_shutdown_slave;
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
@@ -75,6 +84,7 @@ COUNT(*) = 0
 1
 COMMIT;
 SET AUTOCOMMIT=ON;
+connection node_1;
 SELECT COUNT(*) = 35 FROM t1;
 COUNT(*) = 35
 1
@@ -86,6 +96,7 @@ COMMIT;
 SET AUTOCOMMIT=ON;
 Performing State Transfer on a server that starts from a clean var directory
 This is accomplished by shutting down node #2 and removing its var directory before restarting it
+connection node_1;
 CREATE TABLE t1 (f1 CHAR(255)) ENGINE=InnoDB;
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
@@ -95,6 +106,7 @@ INSERT INTO t1 VALUES ('node1_committed_before');
 INSERT INTO t1 VALUES ('node1_committed_before');
 INSERT INTO t1 VALUES ('node1_committed_before');
 COMMIT;
+connection node_2;
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
 INSERT INTO t1 VALUES ('node2_committed_before');
@@ -104,6 +116,7 @@ INSERT INTO t1 VALUES ('node2_committed_before');
 INSERT INTO t1 VALUES ('node2_committed_before');
 COMMIT;
 Shutting down server ...
+connection node_1;
 Cleaning var directory ...
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
@@ -119,6 +132,7 @@ INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
+connect node_1a_galera_st_clean_slave, 127.0.0.1, root, , test, $NODE_MYPORT_1;
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
@@ -126,6 +140,7 @@ INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
+connection node_2;
 Starting server ...
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
@@ -135,6 +150,7 @@ INSERT INTO t1 VALUES ('node2_committed_after');
 INSERT INTO t1 VALUES ('node2_committed_after');
 INSERT INTO t1 VALUES ('node2_committed_after');
 COMMIT;
+connection node_1;
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
@@ -149,6 +165,7 @@ INSERT INTO t1 VALUES ('node1_committed_after');
 INSERT INTO t1 VALUES ('node1_committed_after');
 INSERT INTO t1 VALUES ('node1_committed_after');
 COMMIT;
+connection node_1a_galera_st_clean_slave;
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
@@ -163,6 +180,7 @@ COUNT(*) = 0
 1
 COMMIT;
 SET AUTOCOMMIT=ON;
+connection node_1;
 SELECT COUNT(*) = 35 FROM t1;
 COUNT(*) = 35
 1
@@ -173,6 +191,7 @@ DROP TABLE t1;
 COMMIT;
 SET AUTOCOMMIT=ON;
 Performing State Transfer on a server that has been killed and restarted
+connection node_1;
 CREATE TABLE t1 (f1 CHAR(255)) ENGINE=InnoDB;
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
@@ -182,6 +201,7 @@ INSERT INTO t1 VALUES ('node1_committed_before');
 INSERT INTO t1 VALUES ('node1_committed_before');
 INSERT INTO t1 VALUES ('node1_committed_before');
 COMMIT;
+connection node_2;
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
 INSERT INTO t1 VALUES ('node2_committed_before');
@@ -191,6 +211,7 @@ INSERT INTO t1 VALUES ('node2_committed_before');
 INSERT INTO t1 VALUES ('node2_committed_before');
 COMMIT;
 Killing server ...
+connection node_1;
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
 INSERT INTO t1 VALUES ('node1_committed_during');
@@ -205,6 +226,7 @@ INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
+connect node_1a_galera_st_kill_slave, 127.0.0.1, root, , test, $NODE_MYPORT_1;
 SET AUTOCOMMIT=OFF;
 START TRANSACTION;
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
@@ -212,6 +234,7 @@ INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
+connection node_2;
 Performing --wsrep-recover ...
 Starting server ...
 Using --wsrep-start-position when starting mysqld ...
@@ -223,6 +246,7 @@ INSERT INTO t1 VALUES ('node2_committed_after');
 INSERT INTO t1 VALUES ('node2_committed_after');
 INSERT INTO t1 VALUES ('node2_committed_after');
 COMMIT;
+connection node_1;
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
 INSERT INTO t1 VALUES ('node1_to_be_committed_after');
@@ -237,6 +261,7 @@ INSERT INTO t1 VALUES ('node1_committed_after');
 INSERT INTO t1 VALUES ('node1_committed_after');
 INSERT INTO t1 VALUES ('node1_committed_after');
 COMMIT;
+connection node_1a_galera_st_kill_slave;
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
 INSERT INTO t1 VALUES ('node1_to_be_rollbacked_after');
@@ -251,6 +276,7 @@ COUNT(*) = 0
 1
 COMMIT;
 SET AUTOCOMMIT=ON;
+connection node_1;
 SELECT COUNT(*) = 35 FROM t1;
 COUNT(*) = 35
 1

--- a/mysql-test/suite/galera/t/galera_autoinc_sst_xtrabackup.cnf
+++ b/mysql-test/suite/galera/t/galera_autoinc_sst_xtrabackup.cnf
@@ -4,6 +4,7 @@
 wsrep_sst_method=xtrabackup-v2
 wsrep_sst_auth="root:"
 innodb_safe_truncate=OFF
+# innodb_undo_logs=1
 [mysqld.1]
 wsrep_provider_options='base_port=@mysqld.1.#galera_port;gcache.size=1;pc.ignore_sb=true'

--- a/mysql-test/suite/galera/t/galera_ist_xtrabackup-v2.cnf
+++ b/mysql-test/suite/galera/t/galera_ist_xtrabackup-v2.cnf
@@ -4,6 +4,7 @@
 wsrep_sst_method=xtrabackup-v2
 wsrep_sst_auth=root:
 innodb_safe_truncate=OFF
+innodb_undo_logs=1
 [mysqld.1]
 wsrep_provider_options='base_port=@mysqld.1.#galera_port;pc.ignore_sb=true'

--- a/mysql-test/suite/galera/t/galera_sst_xtrabackup-v2-options.cnf
+++ b/mysql-test/suite/galera/t/galera_sst_xtrabackup-v2-options.cnf
@@ -5,6 +5,7 @@ wsrep_sst_method=xtrabackup-v2
 wsrep_sst_auth="root:"
 wsrep_debug=ON
 innodb_safe_truncate=OFF
+innodb_undo_logs=1
 [xtrabackup]
 backup-locks

--- a/mysql-test/suite/galera/t/galera_sst_xtrabackup-v2.cnf
+++ b/mysql-test/suite/galera/t/galera_sst_xtrabackup-v2.cnf
@@ -5,6 +5,7 @@ wsrep_sst_method=xtrabackup-v2
 wsrep_sst_auth="root:"
 wsrep_debug=ON
 innodb_safe_truncate=OFF
+innodb_undo_logs=1
 [mysqld.1]
 wsrep_provider_options='base_port=@mysqld.1.#galera_port;gcache.size=1;pc.ignore_sb=true'

--- a/mysql-test/suite/galera/t/galera_sst_xtrabackup-v2_data_dir.cnf
+++ b/mysql-test/suite/galera/t/galera_sst_xtrabackup-v2_data_dir.cnf
@@ -5,6 +5,7 @@ wsrep_sst_method=xtrabackup-v2
 wsrep_sst_auth="root:"
 wsrep_debug=ON
 innodb_safe_truncate=OFF
+innodb_undo_logs=1
 [mysqld.1]
 wsrep_provider_options='base_port=@mysqld.1.#galera_port;gcache.size=1;pc.ignore_sb=true'

--- a/mysql-test/suite/galera/t/galera_sst_xtrabackup-v2_encrypt_with_key.cnf
+++ b/mysql-test/suite/galera/t/galera_sst_xtrabackup-v2_encrypt_with_key.cnf
@@ -5,6 +5,7 @@ wsrep_sst_method=xtrabackup-v2
 wsrep_sst_auth="root:"
 wsrep_debug=ON
 innodb_safe_truncate=OFF
+innodb_undo_logs=1
 [SST]
 tkey=@ENV.MYSQL_TEST_DIR/std_data/cakey.pem

--- a/mysql-test/suite/galera_3nodes/r/galera_ist_gcache_rollover.result
+++ b/mysql-test/suite/galera_3nodes/r/galera_ist_gcache_rollover.result
@@ -6,10 +6,10 @@ CREATE TABLE t1 (f1 INTEGER PRIMARY KEY);
 INSERT INTO t1 VALUES (01), (02), (03), (04), (05);
 connection node_2;
 Unloading wsrep provider ...
-SET GLOBAL wsrep_provider = 'none';
+SET GLOBAL wsrep_cluster_address = '';
 connection node_3;
 Unloading wsrep provider ...
-SET GLOBAL wsrep_provider = 'none';
+SET GLOBAL wsrep_cluster_address = '';
 connection node_1;
 INSERT INTO t1 VALUES (11), (12), (13), (14), (15);
 INSERT INTO t1 VALUES (21), (22), (23), (24), (25);

--- a/mysql-test/suite/galera_3nodes/t/galera_ist_gcache_rollover.test
+++ b/mysql-test/suite/galera_3nodes/t/galera_ist_gcache_rollover.test
@@ -29,9 +29,11 @@ INSERT INTO t1 VALUES (01), (02), (03), (04), (05);
 # Disconnect nodes #2 and #3
 --connection node_2
+--let $wsrep_cluster_address_orig2 = `select @@wsrep_cluster_address`
 --source suite/galera/include/galera_stop_replication.inc
 --connection node_3
+--let $wsrep_cluster_address_orig3 = `select @@wsrep_cluster_address`
 --source suite/galera/include/galera_stop_replication.inc
 --connection node_1
@@ -51,8 +53,8 @@ INSERT INTO t1 VALUES (21), (22), (23), (24), (25);
 # ... and restart providers to force IST
 --connection node_2
 --disable_query_log
--eval SET GLOBAL wsrep_provider = '$wsrep_provider_orig';
+SET GLOBAL wsrep_cluster_address='';
--eval SET GLOBAL wsrep_cluster_address = '$wsrep_cluster_address_orig';
+--eval SET GLOBAL wsrep_cluster_address = '$wsrep_cluster_address_orig2';
 --enable_query_log
 --connection node_1
@@ -60,8 +62,8 @@ INSERT INTO t1 VALUES (31), (32), (33), (34), (35);
 --connection node_3
 --disable_query_log
--eval SET GLOBAL wsrep_provider = '$wsrep_provider_orig';
+SET GLOBAL wsrep_cluster_address='';
--eval SET GLOBAL wsrep_cluster_address = '$wsrep_cluster_address_orig';
+--eval SET GLOBAL wsrep_cluster_address = '$wsrep_cluster_address_orig3';
 --enable_query_log
 --connection node_1

--- a/scripts/wsrep_sst_common.sh
+++ b/scripts/wsrep_sst_common.sh
@@ -17,7 +17,7 @@
 # This is a common command line parser to be sourced by other SST scripts
-set -u
+set -ue
 # Setting the path for some utilities on CentOS
 export PATH="$PATH:/usr/sbin:/usr/bin:/sbin:/bin"
@@ -879,9 +879,9 @@ fi
 wsrep_cleanup_progress_file()
 {
-    [ -n "$SST_PROGRESS_FILE" -a \
+    if [ -n "$SST_PROGRESS_FILE" -a -f "$SST_PROGRESS_FILE" ]; then
-      -f "$SST_PROGRESS_FILE" ] && \
+        rm -f "$SST_PROGRESS_FILE" 2>/dev/null || :
-      rm -f "$SST_PROGRESS_FILE" 2>/dev/null || :
+    fi
 }
 wsrep_check_program()
@@ -897,13 +897,10 @@ wsrep_check_program()
 wsrep_check_programs()
 {
    local ret=0
+    while [ $# -gt 0 ]; do
-    while [ $# -gt 0 ]
-    do
        wsrep_check_program "$1" || ret=$?
        shift
    done
    return $ret
 }
@@ -1028,11 +1025,11 @@ check_sockets_utils()
 #
 check_port()
 {
-    local pid="$1"
+    local pid="${1:-0}"
    local port="$2"
    local utils="$3"
-    [ -z "$pid" ] || [ $pid -eq 0 ] && pid='[0-9]+'
+    [ $pid -le 0 ] && pid='[0-9]+'
    local rc=1
@@ -1070,14 +1067,20 @@ check_for_dhparams()
    if [ ! -r "$ssl_dhparams" ]; then
        get_openssl
        if [ -n "$OPENSSL_BINARY" ]; then
-            wsrep_log_info "Could not find dhparams file, creating $ssl_dhparams"
+            wsrep_log_info \
-            if ! "$OPENSSL_BINARY" dhparam -out "$ssl_dhparams" 2048 >/dev/null 2>&1
+                "Could not find dhparams file, creating $ssl_dhparams"
-            then
+            local bug=0
+            local errmsg
+            errmsg=$("$OPENSSL_BINARY" \
+                         dhparam -out "$ssl_dhparams" 2048 2>&1) || bug=1
+            if [ $bug -ne 0 ]; then
+                wsrep_log_info "run: \"$OPENSSL_BINARY\" dhparam -out \"$ssl_dhparams\" 2048"
+                wsrep_log_info "output: $errmsg"
                wsrep_log_error "******** ERROR *****************************************"
                wsrep_log_error "* Could not create the dhparams.pem file with OpenSSL. *"
                wsrep_log_error "********************************************************"
                ssl_dhparams=""
-             fi
+            fi
        else
            # Rollback: if openssl is not installed, then use
            # the default parameters:
@@ -1099,17 +1102,9 @@ verify_ca_matches_cert()
    local ca="$2"
    local cap="$3"
-    # If the openssl utility is not installed, then
-    # we will not do this certificate check:
-    get_openssl
-    if [ -z "$OPENSSL_BINARY" ]; then
-        wsrep_log_info "openssl utility not found"
-        return
-    fi
    local readable=1; [ ! -r "$cert" ] && readable=0
-    [ -n "$ca"  ] &&  [ ! -r "$ca"   ] && readable=0
+         [ -n "$ca"  -a ! -r "$ca"   ] && readable=0
-    [ -n "$cap" ] &&  [ ! -r "$cap"  ] && readable=0
+         [ -n "$cap" -a ! -r "$cap"  ] && readable=0
    if [ $readable -eq 0 ]; then
        wsrep_log_error \
@@ -1117,12 +1112,20 @@ verify_ca_matches_cert()
        exit 22
    fi
+    # If the openssl utility is not installed, then
+    # we will not do this certificate check:
+    get_openssl
+    if [ -z "$OPENSSL_BINARY" ]; then
+        wsrep_log_info "openssl utility not found"
+        return
+    fi
    local not_match=0
    local errmsg
    errmsg=$("$OPENSSL_BINARY" verify -verbose \
-                               ${ca:+ -CAfile} ${ca:+ "$ca"} \
+                 ${ca:+ -CAfile} ${ca:+ "$ca"} \
-                               ${cap:+ -CApath} ${cap:+ "$cap"} \
+                 ${cap:+ -CApath} ${cap:+ "$cap"} \
-                               "$cert" 2>&1) || not_match=1
+                 "$cert" 2>&1) || not_match=1
    if [ $not_match -eq 1 ]; then
        wsrep_log_info "run: \"$OPENSSL_BINARY\" verify -verbose${ca:+ -CAfile \"$ca\"}${cap:+ -CApath \"$cap\"} \"$cert\""
@@ -1158,6 +1161,7 @@ verify_cert_matches_key()
    # If the diff utility is not installed, then
    # we will not do this certificate check:
    if [ -z "$(commandex diff)" ]; then
+        wsrep_log_info "diff utility not found"
        return
    fi
@@ -1165,6 +1169,7 @@ verify_cert_matches_key()
    # we will not do this certificate check:
    get_openssl
    if [ -z "$OPENSSL_BINARY" ]; then
+        wsrep_log_info "openssl utility not found"
        return
    fi
@@ -1253,18 +1258,18 @@ check_pid()
 {
    local pid_file="$1"
    if [ -r "$pid_file" ]; then
-        local pid=$(cat "$pid_file" 2>/dev/null)
+        local pid=$(cat "$pid_file" 2>/dev/null || :)
        if [ -n "$pid" ]; then
-            if [ $pid -ne 0 ]; then
+            if [ $pid -gt 0 ]; then
-                if ps -p "$pid" >/dev/null 2>&1; then
+                if ps -p $pid >/dev/null 2>&1; then
                    CHECK_PID=$pid
                    return 0
                fi
            fi
        fi
        local remove=${2:-0}
-        if [ $remove -eq 1 ]; then
+        if [ $remove -ne 0 ]; then
-            rm -f "$pid_file"
+            rm -f "$pid_file" || :
        fi
    fi
    CHECK_PID=0
@@ -1289,25 +1294,25 @@ cleanup_pid()
    local pid_file="${2:-}"
    local config="${3:-}"
-    if [ $pid -ne 0 ]; then
+    if [ $pid -gt 0 ]; then
        if ps -p $pid >/dev/null 2>&1; then
            if kill $pid >/dev/null 2>&1; then
                sleep 0.5
                local round=0
                local force=0
                while ps -p $pid >/dev/null 2>&1; do
-                   sleep 1
+                    sleep 1
-                   round=$(( round+1 ))
+                    round=$(( round+1 ))
-                   if [ $round -eq 16 ]; then
+                    if [ $round -eq 16 ]; then
-                       if [ $force -eq 0 ]; then
+                        if [ $force -eq 0 ]; then
-                           round=8
+                            round=8
-                           force=1
+                            force=1
-                           kill -9 $pid >/dev/null 2>&1
+                            kill -9 $pid >/dev/null 2>&1 || :
-                           sleep 0.5
+                            sleep 0.5
-                       else
+                        else
-                           return 1
+                            return 1
-                       fi
+                        fi
-                   fi
+                    fi
                done
            elif ps -p $pid >/dev/null 2>&1; then
                wsrep_log_warning "Unable to kill PID=$pid ($pid_file)"
@@ -1316,8 +1321,8 @@ cleanup_pid()
        fi
    fi
-    [ -n "$pid_file" ] && [ -f "$pid_file" ] && rm -f "$pid_file"
+    [ -n "$pid_file" -a -f "$pid_file" ] && rm -f "$pid_file" || :
-    [ -n "$config" ]   && [ -f "$config" ]   && rm -f "$config"
+    [ -n "$config" -a -f "$config" ] && rm -f "$config" || :
    return 0
 }
@@ -1339,3 +1344,46 @@ get_proc()
        fi
    fi
 }
+check_server_ssl_config()
+{
+    # backward-compatible behavior:
+    tcert=$(parse_cnf 'sst' 'tca')
+    tcap=$(parse_cnf 'sst' 'tcapath')
+    tpem=$(parse_cnf 'sst' 'tcert')
+    tkey=$(parse_cnf 'sst' 'tkey')
+    # reading new ssl configuration options:
+    local tcert2=$(parse_cnf "$encgroups" 'ssl-ca')
+    local tcap2=$(parse_cnf "$encgroups" 'ssl-capath')
+    local tpem2=$(parse_cnf "$encgroups" 'ssl-cert')
+    local tkey2=$(parse_cnf "$encgroups" 'ssl-key')
+    # if there are no old options, then we take new ones:
+    if [ -z "$tcert" -a -z "$tcap" -a -z "$tpem" -a -z "$tkey" ]; then
+        tcert="$tcert2"
+        tcap="$tcap2"
+        tpem="$tpem2"
+        tkey="$tkey2"
+    # checking for presence of the new-style SSL configuration:
+    elif [ -n "$tcert2" -o -n "$tcap2" -o -n "$tpem2" -o -n "$tkey2" ]; then
+        if [ "$tcert" != "$tcert2" -o \
+             "$tcap"  != "$tcap2"  -o \
+             "$tpem"  != "$tpem2"  -o \
+             "$tkey"  != "$tkey2" ]
+        then
+            wsrep_log_info \
+               "new ssl configuration options (ssl-ca[path], ssl-cert" \
+               "and ssl-key) are ignored by SST due to presence" \
+               "of the tca[path], tcert and/or tkey in the [sst] section"
+        fi
+    fi
+    if [ -n "$tcert" ]; then
+        tcert=$(trim_string "$tcert")
+        if [ "${tcert%/}" != "$tcert" -o -d "$tcert" ]; then
+            tcap="$tcert"
+            tcert=""
+        fi
+    fi
+    if [ -n "$tcap" ]; then
+        tcap=$(trim_string "$tcap")
+    fi
+}
--- a/scripts/wsrep_sst_mariabackup.sh
+++ b/scripts/wsrep_sst_mariabackup.sh
@@ -30,7 +30,6 @@ eformat=""
 ekey=""
 ekeyfile=""
 encrypt=0
-ecode=0
 ssyslog=""
 ssystag=""
 BACKUP_PID=""
@@ -465,49 +464,6 @@ adjust_progress()
 encgroups='--mysqld|sst|xtrabackup'
-check_server_ssl_config()
-{
-    # backward-compatible behavior:
-    tcert=$(parse_cnf 'sst' 'tca')
-    tcap=$(parse_cnf 'sst' 'tcapath')
-    tpem=$(parse_cnf 'sst' 'tcert')
-    tkey=$(parse_cnf 'sst' 'tkey')
-    # reading new ssl configuration options:
-    local tcert2=$(parse_cnf "$encgroups" 'ssl-ca')
-    local tcap2=$(parse_cnf "$encgroups" 'ssl-capath')
-    local tpem2=$(parse_cnf "$encgroups" 'ssl-cert')
-    local tkey2=$(parse_cnf "$encgroups" 'ssl-key')
-    # if there are no old options, then we take new ones:
-    if [ -z "$tcert" -a -z "$tcap" -a -z "$tpem" -a -z "$tkey" ]; then
-        tcert="$tcert2"
-        tcap="$tcap2"
-        tpem="$tpem2"
-        tkey="$tkey2"
-    # checking for presence of the new-style SSL configuration:
-    elif [ -n "$tcert2" -o -n "$tcap2" -o -n "$tpem2" -o -n "$tkey2" ]; then
-        if [ "$tcert" != "$tcert2" -o \
-             "$tcap"  != "$tcap2"  -o \
-             "$tpem"  != "$tpem2"  -o \
-             "$tkey"  != "$tkey2" ]
-        then
-            wsrep_log_info \
-               "new ssl configuration options (ssl-ca[path], ssl-cert" \
-               "and ssl-key) are ignored by SST due to presence" \
-               "of the tca[path], tcert and/or tkey in the [sst] section"
-        fi
-    fi
-    if [ -n "$tcert" ]; then
-        tcert=$(trim_string "$tcert")
-        if [ "${tcert%/}" != "$tcert" ] || [ -d "$tcert" ]; then
-            tcap="$tcert"
-            tcert=""
-        fi
-    fi
-    if [ -n "$tcap" ]; then
-        tcap=$(trim_string "$tcap")
-    fi
-}
 read_cnf()
 {
    sfmt=$(parse_cnf sst streamfmt 'mbstream')
@@ -647,7 +603,7 @@ cleanup_at_exit()
                cleanup_pid $CHECK_PID "$BACKUP_PID"
            fi
        fi
-        [ -f "$DATA/$IST_FILE" ] && rm -f "$DATA/$IST_FILE"
+        [ -f "$DATA/$IST_FILE" ] && rm -f "$DATA/$IST_FILE" || :
    fi
    if [ -n "$progress" -a -p "$progress" ]; then
@@ -658,27 +614,31 @@ cleanup_at_exit()
    wsrep_log_info "Cleaning up temporary directories"
    if [ "$WSREP_SST_OPT_ROLE" = 'joiner' ]; then
-        if [ -n "$STATDIR" ]; then
+        [ -n "$STATDIR" -a -d "$STATDIR" ] && rm -rf "$STATDIR" || :
-           [ -d "$STATDIR" ] && rm -rf "$STATDIR"
-        fi
    else
        [ -n "$xtmpdir" -a -d "$xtmpdir" ] && rm -rf "$xtmpdir" || :
        [ -n "$itmpdir" -a -d "$itmpdir" ] && rm -rf "$itmpdir" || :
    fi
    # Final cleanup
-    pgid=$(ps -o pgid= $$ | grep -o '[0-9]*')
+    pgid=$(ps -o pgid= $$ 2>/dev/null | grep -o '[0-9]*' || :)
    # This means no setsid done in mysqld.
    # We don't want to kill mysqld here otherwise.
-    if [ $$ -eq $pgid ]; then
+    if [ -n "$pgid" ]; then
-        # This means a signal was delivered to the process.
+        if [ $$ -eq $pgid ]; then
-        # So, more cleanup.
+            # This means a signal was delivered to the process.
-        if [ $estatus -ge 128 ]; then
+            # So, more cleanup.
-            kill -KILL -- -$$ || :
+            if [ $estatus -ge 128 ]; then
+                kill -KILL -- -$$ || :
+            fi
        fi
    fi
+    if [ -n "${SST_PID:-}" ]; then
+        [ -f "$SST_PID" ] && rm -f "$SST_PID" || :
+    fi
    exit $estatus
 }
@@ -967,7 +927,7 @@ setup_commands()
    fi
    INNOAPPLY="$BACKUP_BIN --prepare$disver$recovery${iapts:+ }$iapts$INNOEXTRA --target-dir='$DATA' --datadir='$DATA'$mysqld_args $INNOAPPLY"
    INNOMOVE="$BACKUP_BIN$WSREP_SST_OPT_CONF --move-back$disver${impts:+ }$impts --force-non-empty-directories --target-dir='$DATA' --datadir='${TDATA:-$DATA}' $INNOMOVE"
-    INNOBACKUP="$BACKUP_BIN$WSREP_SST_OPT_CONF --backup$disver${iopts:+ }$iopts $tmpopts$INNOEXTRA --galera-info --stream=$sfmt --target-dir='$itmpdir' --datadir='$DATA'$mysqld_args $INNOBACKUP"
+    INNOBACKUP="$BACKUP_BIN$WSREP_SST_OPT_CONF --backup$disver${iopts:+ }$iopts$tmpopts$INNOEXTRA --galera-info --stream=$sfmt --target-dir='$itmpdir' --datadir='$DATA'$mysqld_args $INNOBACKUP"
 }
 get_stream
@@ -995,7 +955,7 @@ then
        fi
        wsrep_log_info "Using '$xtmpdir' as mariabackup temporary directory"
-        tmpopts="--tmpdir='$xtmpdir'"
+        tmpopts=" --tmpdir='$xtmpdir'"
        itmpdir="$(mktemp -d)"
        wsrep_log_info "Using '$itmpdir' as mariabackup working directory"
@@ -1161,10 +1121,23 @@ then
        impts="--parallel=$backup_threads${impts:+ }$impts"
    fi
-    stagemsg='Joiner-Recv'
+    SST_PID="$WSREP_SST_OPT_DATA/wsrep_sst.pid"
+    # give some time for previous SST to complete:
+    check_round=0
+    while check_pid "$SST_PID" 0; do
+        wsrep_log_info "previous SST is not completed, waiting for it to exit"
+        check_round=$(( check_round + 1 ))
+        if [ $check_round -eq 10 ]; then
+            wsrep_log_error "previous SST script still running."
+            exit 114 # EALREADY
+        fi
+        sleep 1
+    done
+    echo $$ > "$SST_PID"
-    sencrypted=1
+    stagemsg='Joiner-Recv'
-    nthreads=1
    MODULE="xtrabackup_sst"
@@ -1208,7 +1181,7 @@ then
    fi
    get_keys
-    if [ $encrypt -eq 1 -a $sencrypted -eq 1 ]; then
+    if [ $encrypt -eq 1 ]; then
        strmcmd="$ecmd | $strmcmd"
    fi
@@ -1263,12 +1236,14 @@ then
        if [ -n "$WSREP_SST_OPT_BINLOG" ]; then
            binlog_dir=$(dirname "$WSREP_SST_OPT_BINLOG")
-            cd "$binlog_dir"
+            if [ -d "$binlog_dir" ]; then
-            wsrep_log_info "Cleaning the binlog directory $binlog_dir as well"
+                cd "$binlog_dir"
-            rm -fv "$WSREP_SST_OPT_BINLOG".[0-9]* 1>&2 \+ || :
+                wsrep_log_info "Cleaning the binlog directory $binlog_dir as well"
-            [ -f "$WSREP_SST_OPT_BINLOG_INDEX" ] && \
+                rm -fv "$WSREP_SST_OPT_BINLOG".[0-9]* 1>&2 \+ || :
-                rm -fv "$WSREP_SST_OPT_BINLOG_INDEX" 1>&2 \+ || :
+                [ -f "$WSREP_SST_OPT_BINLOG_INDEX" ] && \
-            cd "$OLD_PWD"
+                    rm -fv "$WSREP_SST_OPT_BINLOG_INDEX" 1>&2 \+
+                cd "$OLD_PWD"
+            fi
        fi
        TDATA="$DATA"
@@ -1285,7 +1260,7 @@ then
        fi
        # Compact backups are not supported by mariabackup
-        if grep -q -F 'compact = 1' "$DATA/xtrabackup_checkpoints"; then
+        if grep -qw -F 'compact = 1' "$DATA/xtrabackup_checkpoints"; then
            wsrep_log_info "Index compaction detected"
            wsrel_log_error "Compact backups are not supported by mariabackup"
            exit 2

--- a/scripts/wsrep_sst_rsync.sh
+++ b/scripts/wsrep_sst_rsync.sh
--- a/scripts/wsrep_sst_xtrabackup-v2.sh
+++ b/scripts/wsrep_sst_xtrabackup-v2.sh
@@ -31,7 +31,6 @@ eformat=""
 ekey=""
 ekeyfile=""
 encrypt=0
-ecode=0
 ssyslog=""
 ssystag=""
 BACKUP_PID=""
@@ -160,7 +159,7 @@ get_keys()
        return
    fi
-    wsrep_log_info "Key based encryption enabled in my.cnf - supported only from Xtrabackup 2.1.4"
+    wsrep_log_info "Key based encryption enabled in my.cnf"
    if [ -z "$ealgo" ]; then
        wsrep_log_error "FATAL: Encryption algorithm empty from my.cnf, bailing out"
@@ -470,49 +469,6 @@ adjust_progress()
 encgroups='--mysqld|sst|xtrabackup'
-check_server_ssl_config()
-{
-    # backward-compatible behavior:
-    tcert=$(parse_cnf 'sst' 'tca')
-    tcap=$(parse_cnf 'sst' 'tcapath')
-    tpem=$(parse_cnf 'sst' 'tcert')
-    tkey=$(parse_cnf 'sst' 'tkey')
-    # reading new ssl configuration options:
-    local tcert2=$(parse_cnf "$encgroups" 'ssl-ca')
-    local tcap2=$(parse_cnf "$encgroups" 'ssl-capath')
-    local tpem2=$(parse_cnf "$encgroups" 'ssl-cert')
-    local tkey2=$(parse_cnf "$encgroups" 'ssl-key')
-    # if there are no old options, then we take new ones:
-    if [ -z "$tcert" -a -z "$tcap" -a -z "$tpem" -a -z "$tkey" ]; then
-        tcert="$tcert2"
-        tcap="$tcap2"
-        tpem="$tpem2"
-        tkey="$tkey2"
-    # checking for presence of the new-style SSL configuration:
-    elif [ -n "$tcert2" -o -n "$tcap2" -o -n "$tpem2" -o -n "$tkey2" ]; then
-        if [ "$tcert" != "$tcert2" -o \
-             "$tcap"  != "$tcap2"  -o \
-             "$tpem"  != "$tpem2"  -o \
-             "$tkey"  != "$tkey2" ]
-        then
-            wsrep_log_info \
-               "new ssl configuration options (ssl-ca[path], ssl-cert" \
-               "and ssl-key) are ignored by SST due to presence" \
-               "of the tca[path], tcert and/or tkey in the [sst] section"
-        fi
-    fi
-    if [ -n "$tcert" ]; then
-        tcert=$(trim_string "$tcert")
-        if [ "${tcert%/}" != "$tcert" ] || [ -d "$tcert" ]; then
-            tcap="$tcert"
-            tcert=""
-        fi
-    fi
-    if [ -n "$tcap" ]; then
-        tcap=$(trim_string "$tcap")
-    fi
-}
 read_cnf()
 {
    sfmt=$(parse_cnf sst streamfmt 'xbstream')
@@ -659,7 +615,7 @@ cleanup_at_exit()
                cleanup_pid $CHECK_PID "$BACKUP_PID"
            fi
        fi
-        [ -f "$DATA/$IST_FILE" ] && rm -f "$DATA/$IST_FILE"
+        [ -f "$DATA/$IST_FILE" ] && rm -f "$DATA/$IST_FILE" || :
    fi
    if [ -n "$progress" -a -p "$progress" ]; then
@@ -670,27 +626,31 @@ cleanup_at_exit()
    wsrep_log_info "Cleaning up temporary directories"
    if [ "$WSREP_SST_OPT_ROLE" = 'joiner' ]; then
-        if [ -n "$STATDIR" ]; then
+        [ -n "$STATDIR" -a -d "$STATDIR" ] && rm -rf "$STATDIR" || :
-           [ -d "$STATDIR" ] && rm -rf "$STATDIR"
-        fi
    else
        [ -n "$xtmpdir" -a -d "$xtmpdir" ] && rm -rf "$xtmpdir" || :
        [ -n "$itmpdir" -a -d "$itmpdir" ] && rm -rf "$itmpdir" || :
    fi
    # Final cleanup
-    pgid=$(ps -o pgid= $$ | grep -o '[0-9]*')
+    pgid=$(ps -o pgid= $$ 2>/dev/null | grep -o '[0-9]*' || :)
    # This means no setsid done in mysqld.
    # We don't want to kill mysqld here otherwise.
-    if [ $$ -eq $pgid ]; then
+    if [ -n "$pgid" ]; then
-        # This means a signal was delivered to the process.
+        if [ $$ -eq $pgid ]; then
-        # So, more cleanup.
+            # This means a signal was delivered to the process.
-        if [ $estatus -ge 128 ]; then
+            # So, more cleanup.
-            kill -KILL -- -$$ || :
+            if [ $estatus -ge 128 ]; then
+                kill -KILL -- -$$ || :
+            fi
        fi
    fi
+    if [ -n "${SST_PID:-}" ]; then
+        [ -f "$SST_PID" ] && rm -f "$SST_PID" || :
+    fi
    exit $estatus
 }
@@ -862,7 +822,7 @@ monitor_process()
    done
 }
-# check the version, we require XB-2.4 to ensure that we can pass the
+# check the version, we require XB-2.3.5 to ensure that we can pass the
 # datadir via the command-line option
 XB_REQUIRED_VERSION="2.3.5"
@@ -992,13 +952,13 @@ setup_commands()
    if [ -n "$INNODB_FORCE_RECOVERY" ]; then
        recovery=" --innodb-force-recovery=$INNODB_FORCE_RECOVERY"
    fi
-    INNOAPPLY="$BACKUP_BIN$disver$recovery${iapts:+ }$iapts$INNOEXTRA --apply-log $rebuildcmd '$DATA' $INNOAPPLY"
+    INNOAPPLY="$BACKUP_BIN$disver$recovery${iapts:+ }$iapts$INNOEXTRA --apply-log${rebuildcmd:+ }$rebuildcmd --datadir='$DATA' '$DATA' $INNOAPPLY"
-    INNOMOVE="$BACKUP_BIN$WSREP_SST_OPT_CONF --move-back$disver${impts:+ }$impts --force-non-empty-directories '$DATA' $INNOMOVE"
+    INNOMOVE="$BACKUP_BIN$WSREP_SST_OPT_CONF --move-back$disver${impts:+ }$impts --force-non-empty-directories --datadir='${TDATA:-$DATA}' '$DATA' $INNOMOVE"
    local sfmt_work="$sfmt"
    if [ "$sfmt" = 'mbstream' ]; then
        sfmt_work='xbstream'
    fi
-    INNOBACKUP="$BACKUP_BIN$WSREP_SST_OPT_CONF$disver${iopts:+ }$iopts $tmpopts$INNOEXTRA --galera-info --stream=$sfmt_work '$itmpdir' $INNOBACKUP"
+    INNOBACKUP="$BACKUP_BIN$WSREP_SST_OPT_CONF$disver${iopts:+ }$iopts$tmpopts$INNOEXTRA --galera-info --stream=$sfmt_work --datadir='$DATA' '$itmpdir' $INNOBACKUP"
 }
 get_stream
@@ -1026,7 +986,7 @@ then
        fi
        wsrep_log_info "Using '$xtmpdir' as xtrabackup temporary directory"
-        tmpopts="--tmpdir='$xtmpdir'"
+        tmpopts=" --tmpdir='$xtmpdir'"
        itmpdir="$(mktemp -d)"
        wsrep_log_info "Using '$itmpdir' as xtrabackup working directory"
@@ -1192,10 +1152,23 @@ then
        impts="--parallel=$backup_threads${impts:+ }$impts"
    fi
-    stagemsg='Joiner-Recv'
+    SST_PID="$WSREP_SST_OPT_DATA/wsrep_sst.pid"
+    # give some time for previous SST to complete:
+    check_round=0
+    while check_pid "$SST_PID" 0; do
+        wsrep_log_info "previous SST is not completed, waiting for it to exit"
+        check_round=$(( check_round + 1 ))
+        if [ $check_round -eq 10 ]; then
+            wsrep_log_error "previous SST script still running."
+            exit 114 # EALREADY
+        fi
+        sleep 1
+    done
+    echo $$ > "$SST_PID"
-    sencrypted=1
+    stagemsg='Joiner-Recv'
-    nthreads=1
    MODULE="xtrabackup_sst"
@@ -1239,7 +1212,7 @@ then
    fi
    get_keys
-    if [ $encrypt -eq 1 -a $sencrypted -eq 1 ]; then
+    if [ $encrypt -eq 1 ]; then
        strmcmd="$ecmd | $strmcmd"
    fi
@@ -1294,12 +1267,14 @@ then
        if [ -n "$WSREP_SST_OPT_BINLOG" ]; then
            binlog_dir=$(dirname "$WSREP_SST_OPT_BINLOG")
-            cd "$binlog_dir"
+            if [ -d "$binlog_dir" ]; then
-            wsrep_log_info "Cleaning the binlog directory $binlog_dir as well"
+                cd "$binlog_dir"
-            rm -fv "$WSREP_SST_OPT_BINLOG".[0-9]* 1>&2 \+ || :
+                wsrep_log_info "Cleaning the binlog directory $binlog_dir as well"
-            [ -f "$WSREP_SST_OPT_BINLOG_INDEX" ] && \
+                rm -fv "$WSREP_SST_OPT_BINLOG".[0-9]* 1>&2 \+ || :
-                rm -fv "$WSREP_SST_OPT_BINLOG_INDEX" 1>&2 \+ || :
+                [ -f "$WSREP_SST_OPT_BINLOG_INDEX" ] && \
-            cd "$OLD_PWD"
+                    rm -fv "$WSREP_SST_OPT_BINLOG_INDEX" 1>&2 \+
+                cd "$OLD_PWD"
+            fi
        fi
        TDATA="$DATA"
@@ -1316,7 +1291,7 @@ then
        fi
        # Rebuild indexes for compact backups
-        if grep -q -F 'compact = 1' "$DATA/xtrabackup_checkpoints"; then
+        if grep -qw -F 'compact = 1' "$DATA/xtrabackup_checkpoints"; then
            wsrep_log_info "Index compaction detected"
            get_proc
            nthreads=$(parse_cnf "$encgroups" 'rebuild-threads' $nproc)