I did not understand your point about master/slave switch. This time I took backup with 2.3.9 on PS 5.6 master server with --history option:
xtrabackup --defaults-file=/home/shahriyar.rzaev/sandboxes/rsandbox_Percona-Server-5_6_36/master/my.sandbox.cnf --history --user=msandbox --password='msandbox' --target-dir=/home/shahriyar.rzaev/backup_dir/ps_5.6_master/full/2017-08-02_08-41-18 --backup --host=127.0.0.1 --port=23901 --encrypt=AES256 --encrypt-key='VVTBwgM4UhwkTTV98fhuj+D1zyWoA89K' --encrypt-threads=4 --encrypt-chunk-size=65536 --stream="xbstream" > /home/shahriyar.rzaev/backup_dir/ps_5.6_master/full/2017-08-02_08-41-18/full_backup.stream
And I did it twice:
> select count(*) from xtrabackup_history; +----------+ | count(*) | +----------+ | 2 | +----------+ 1 row in set (0.00 sec)
So the history is there.
Still could not reproduce.
I did not understand your point about master/slave switch.
This time I took backup with 2.3.9 on PS 5.6 master server with --history option:
xtrabackup --defaults- file=/home/ shahriyar. rzaev/sandboxes /rsandbox_ Percona- Server- 5_6_36/ master/ my.sandbox. cnf --history --user=msandbox --password= 'msandbox' --target- dir=/home/ shahriyar. rzaev/backup_ dir/ps_ 5.6_master/ full/2017- 08-02_08- 41-18 --backup --host=127.0.0.1 --port=23901 --encrypt=AES256 --encrypt- key='VVTBwgM4Uh wkTTV98fhuj+ D1zyWoA89K' --encrypt-threads=4 --encrypt- chunk-size= 65536 --stream="xbstream" > /home/shahriyar .rzaev/ backup_ dir/ps_ 5.6_master/ full/2017- 08-02_08- 41-18/full_ backup. stream
And I did it twice:
> select count(*) from xtrabackup_history;
+----------+
| count(*) |
+----------+
| 2 |
+----------+
1 row in set (0.00 sec)
So the history is there.
Still could not reproduce.