# Validating backup & restore procedure

**URL:** <https://forums.percona.com/t/validating-backup-restore-procedure/5148>\
**Category:** Percona XtraBackup\
**Created:** [October 13, 2016, 10:41am UTC](https://forums.percona.com/t/validating-backup-restore-procedure/5148 "2016-10-13T10:41:10Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![mjuszczak](https://avatars.discourse-cdn.com/v4/letter/m/919ad9/32.png) [@mjuszczak](https://forums.percona.com/u/mjuszczak)\
**Post date:** [October 13, 2016, 10:41am UTC](https://forums.percona.com/t/validating-backup-restore-procedure/5148/1 "2016-10-13T10:41:10Z")

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We are looking to validate our restore procedure from an xbstream-based backup, because it doesn’t seem to be well documented, and we’re having some corruption issues during our test restores.

The backup configuration is:  
[INDENT][xtrabackup]  
compress  
compress-threads=4  
host=localhost  
user=backup  
password=backuppass  
target\_dir=/data/backups

[xtrabackup\_decompress\_decrypt]  
decompress  
decompress-threads=4[/INDENT]

The backup is taken with:  
[INDENT]xtrabackup --backup --stream=xbstream \> /data/backups/2016-09-26\_01-54-10.xbstream  
[/INDENT]  
The backup is then restored with these commands:

[INDENT]$ sudo service mysql stop

# Extract the backup to /tmp/restore

$ mkdir -p /tmp/restore  
$ xbstream -x -v -C /tmp/restore \< /data/backups/2016-09-26\_01-54-10.xbstream

# Decompress the backup files, remove compressed versions

$ pushd /tmp/restore  
$ for i in `find . -iname "*\.qp"`; do qpress -do $i \> $(dirname $i)/$(basename $i .qp) && rm -f $i; done  
$ popd

# Move the backup files to back to datadir

$ sudo rsync -avzh /tmp/restore/ /data/mysql/  
$ sudo chown -R mysql: /data/mysql  
$ sudo service mysql start

# if all goes well, delete /tmp/restore

$ rm -rf /tmp/restore/  
[/INDENT]  
[INDENT] [/INDENT]  
However, we’re getting some ibdata1/log file position mismatch errors and MySQL is not starting (restoring to same server): [INDENT]Oct 13 14:25:27 test mysqld: 2016-10-13 14:25:27 140163571337152 [Note] InnoDB: The log sequence numbers 770055386153 and 770055386153 in ibdata files do not match the log sequence number 1144662140864 in the ib\_logfiles!  
Oct 13 14:25:27 test mysqld: 2016-10-13 14:25:27 140163571337152 [Note] InnoDB: Database was not shutdown normally!  
Oct 13 14:25:27 test mysqld: 2016-10-13 14:25:27 140163571337152 [Note] InnoDB: Starting crash recovery.  
Oct 13 14:25:27 test mysqld: 2016-10-13 14:25:27 140163571337152 [Note] InnoDB: Reading tablespace information from the .ibd files…  
Oct 13 14:25:27 test mysqld: 2016-10-13 14:25:27 140163571337152 [Note] InnoDB: Restoring possible half-written data pages  
Oct 13 14:25:27 test mysqld: 2016-10-13 14:25:27 140163571337152 [Note] InnoDB: from the doublewrite buffer…  
Oct 13 14:25:27 test mysqld: InnoDB: Error: trying to access page number 3636950279 in space 0,  
Oct 13 14:25:27 test mysqld: InnoDB: space name ./ibdata1,  
Oct 13 14:25:27 test mysqld: InnoDB: which is outside the tablespace bounds.  
Oct 13 14:25:27 test mysqld: InnoDB: Byte offset 0, len 16384, i/o type 10.  
Oct 13 14:25:27 test mysqld: InnoDB: If you get this error at mysqld startup, please check that  
Oct 13 14:25:27 test mysqld: InnoDB: your my.cnf matches the ibdata files that you have in the  
Oct 13 14:25:27 test mysqld: InnoDB: MySQL server.[/INDENT]  
Does anyone have any ideas on whether the restore procedure we’re using is valid? Thanks, Matt