MySQL Enterprise Backup User's Guide (Version 8.0.39)
The InnoDB-related data files that are backed up include the ibdata* files (which represent the system tablespace and possibly the data for some user tables), any .ibd files (which contains data from user tables created with the file-per-table setting enabled), and the data extracted from the ib_logfile* files (the redo log information representing changes that occur while the backup is running), which is stored in a new backup file ibbackup_logfile.
If you use the compressed backup feature, the
.ibd
files are renamed in their compressed
form to .ibz files.
The backed-up files, as they are originally copied, form a
raw backup that requires
further processing. The apply
step (either as part of a
copy-back-and-apply-log
command or a
backup-and-apply-log
command, or as
a separate apply-log
command)
updates the backed-up files based on the changes recorded in the
ibbackup_logfile
file. At this point, the
data corresponds to a single point in time.
To avoid concurrency issues during backups of busy databases,
you can use the --only-innodb
option to back up only InnoDB tables and the associated data.