---------- ERROR OUTPUT from mariabackup ----------
181230 00:00:12 Connecting to MySQL server host: localhost, user: bckadmin, password: set, port: not set, socket: /some_socket.sock
Using server version 10.3.11-MariaDB-log
/usr/bin/mariabackup based on MariaDB server 10.3.11-MariaDB Linux (x86_64)
incremental backup from 196297514728 is enabled.
mariabackup: uses posix_fadvise().
mariabackup: cd to /some_path_1
mariabackup: open files limit requested 4096, set to 4096
mariabackup: using the following InnoDB configuration:
mariabackup: innodb_data_home_dir = /some_path_1
mariabackup: innodb_data_file_path = ibdata1:64M;ibdata2:64M:autoextend
mariabackup: innodb_log_group_home_dir = /some_path_1
2018-12-30 00:00:12 0x7fced22098c0 InnoDB: Using Linux native AIO
2018-12-30 0:00:12 0 [Note] InnoDB: Number of pools: 1
mariabackup: Generating a list of tablespaces
2018-12-30 0:00:12 0 [Warning] InnoDB: Allocated tablespace ID 338 for some_table, old maximum was 0
mariabackup: Error: xtrabackup_copy_logfile() failed.
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See also https://support.mariadb.com/view.php?id=24908.