Some info about ib_logfile0 and ib_logfile1

MySQL & MariaDB Percona XtraBackup
1

Hello everyone,

I’m new to this backup and sorry if the question is dumb. After executing the backup command:

innobackupex --user=xxxx --password=xxxxxxx /var/lib/mysql_backup

it ended up with: innobackupex: completed OK!

so far so good, but i looked at the folder’s size and it was 355 MB , but earlier backups are 4,1 GB. When i opened them they had these two files: ib_logfile0 and ib_logfile1, which are missing in the new backup folder.

Can you explain me what are these and why are they missing in the new backup folder?

2

The log files will be missing until you prepare the backup.
The size still seems very small - do you have very large log files?

3

This is what’s in the folder of the previous backup that was created:

4.0K backup-my.cnf
58M ibdata1
2.1G ib_logfile0
2.1G ib_logfile1
1.0M mysql
212K performance_schema
7.1M radius
27M xbench
4.0K xtrabackup_binary
4.0K xtrabackup_binlog_pos_innodb
4.0K xtrabackup_checkpoints
2.0M xtrabackup_logfile

And this is the latest:

4.0K backup-my.cnf
59M ibdata1
1.1M mysql
212K performance_schema
260M radius
3.7M radmin
26M xbench
4.0K xtrabackup_binary
4.0K xtrabackup_checkpoints
7.3M xtrabackup_logfile

So the missing files are ib_logfile0, ib_logfile1 and xtrabackup_binlog_pos_innodb. By logfiles, which logs do you mean exactly?
So after preparing the backup i’ll have ib_logfiles? But what about xtrabackup_binlog_pos_innodb? In the history command I can’t find how the previous backup was created. It was over a year ago and there is no one working here from that period to ask them.

4

Percona has an easy to follow guide on taking, preparing, and restoring a full backup:

[url]Percona XtraBackup

The files you are missing will be created once you run the apply-log step to prepare the backup prior to restore.

5

I followed the guide, but it says nothing about these ib_logfiles or I’ve missed it. Anyway, I understood when and how they are created. Thank you for the help.

6

The guide is really just meant to show you how to create, prepare,and restore a backup with as little detail / complication as possible to get you going. If you are curious for more details, there is a ton of extra information in the Xtrabackup/Innobackupex documentation you could spend all day reading if interested. But that might put you to sleep at some point. :wink: