mariabackup hangs at FLUSH TABLES WITH READ LOCK when Node is wsrep_desync

MariaDB [(none)]> set global wsrep_desync=1;

Query OK, 0 rows affected (0.001 sec)

MariaDB [(none)]> flush tables with read lock;

Query OK, 0 rows affected (0.000 sec)

mariabackup --backup -u root -p1 --target-dir=/var/mariadb/backup/B1

180418 14:01:52 Connecting to MySQL server host: localhost, user: root, password: set, port: not set, socket: not set

Using server version 10.3.6-MariaDB

mariabackup based on MariaDB server 10.3.6-MariaDB Linux (x86_64)

mariabackup: uses posix_fadvise().

mariabackup: cd to /var/lib/mysql/

mariabackup: open files limit requested 0, set to 1024

mariabackup: using the following InnoDB configuration:

mariabackup:   innodb_data_home_dir = .

mariabackup:   innodb_data_file_path = ibdata1:12M:autoextend

mariabackup:   innodb_log_group_home_dir = ./

2018-04-18 14:01:52 0 [Note] InnoDB: Number of pools: 1

mariabackup: Generating a list of tablespaces

2018-04-18 14:01:52 0 [Warning] InnoDB: Allocated tablespace ID 154 for fi/people, old maximum was 0

2018-04-18 14:01:52 0 [Warning] InnoDB: Open files 60 exceeds the limit 18446744073709551615

180418 14:01:52 >> log scanned up to (48213433987)

180418 14:01:52 [01] Copying ./ibdata1 to /var/mariadb/backup/B1/ibdata1

2018-04-18 14:01:53 0 [Warning] InnoDB: Open files 61 exceeds the limit 18446744073709551615

180418 14:01:53 >> log scanned up to (48213433987)

180418 14:01:54 [01]        ...done

180418 14:01:54 [01] Copying ./fi/people.ibd to /var/mariadb/backup/B1/fi/people.ibd

180418 14:01:54 [01]        ...done

~~~~~

180418 14:44:08 [01] Copying ./tpcc/ORDER_LINE.ibd to /var/mariadb/backup/B1/tpcc/ORDER_LINE.ibd

180418 14:44:09 [01]        ...done

180418 14:44:09 [01] Copying ./tpcc/STOCK.ibd to /var/mariadb/backup/B1/tpcc/STOCK.ibd

180418 14:44:11 [01]        ...done

180418 14:44:11 [01] Copying ./tpcc/WAREHOUSE.ibd to /var/mariadb/backup/B1/tpcc/WAREHOUSE.ibd

180418 14:44:11 [01]        ...done

180418 14:44:11 Executing FLUSH NO_WRITE_TO_BINLOG TABLES...

180418 14:44:11 Executing FLUSH TABLES WITH READ LOCK...

MariaDB [(none)]> show processlist ;

|  88 | root        | localhost | NULL | Query   |     0 | Init                     | show processlist            |                                              0.000 |

| 120 | root        | localhost | NULL | Sleep   |  2386 |                          | NULL                        |                                              0.000 |

| 125 | root        | localhost | NULL | Query   |  1345 | Init                     | FLUSH TABLES WITH READ LOCK |                                              0.000 |

+-----+-------------+-----------+------+---------+-------+--------------------------+-----------------------------+                                          ----------+

73 rows in set (0.000 sec)