Incremental Backups Failing

Hello, everyone -

I have a situation where xtrabackup fails to create an incremental backup from time to time, however it seems to be random and intermittent. I have been unable to figure out what happens to cause the backups to fail.

A tail of the log file entry for the error looks like this:

IMPORTANT: Please check that the backup run completes successfully.
At the end of a successful backup run innobackupex
prints “completed OK!”.

innobackupex: Using mysql Ver 14.14 Distrib 5.5.25, for Linux (x86_64) using re
adline 5.1
innobackupex: Using mysql server version Copyright © 2000, 2011, Oracle and/or
its affiliates. All rights reserved.

innobackupex: Created backup directory /data/backups/incremental/04
130315 04:00:09 innobackupex: Starting mysql with options: --password=xxxxxxxx
–user=‘bkpuser’ --unbuffered –
130315 04:00:09 innobackupex: Connected to database with mysql child process (p
130315 04:00:11 innobackupex: Connection to database server closed

130315 04:00:11 innobackupex: Starting ibbackup with command: xtrabackup_55 --defaults-group=“mysqld” --backup --suspend-at-end --target-dir=/data/backups/incremental/04 --incremental-basedir=’/data/backups/incremental/03’ --parallel=4
innobackupex: Waiting for ibbackup (pid=24908) to suspend
innobackupex: Suspend file ‘/data/backups/incremental/04/xtrabackup_suspended’

xtrabackup: Error: cannot open /data/backups/incremental/03/xtrabackup_checkpoints
xtrabackup: error: failed to read metadata from /data/backups/incremental/03/xtrabackup_checkpoints
innobackupex: Error: ibbackup child process has died at /usr/bin/innobackupex line 374.

  • ‘[’ 2 -eq 0 ‘]’
  • echo ‘\nIncremental Backup failed at 04\n’
    \nIncremental Backup failed at 04\n
  • echo -e 'Incremental Backup failed at 04: ’
  • mail -s ‘Please check the status log.’ <email_address> – -r bkpuser@localhost
  • ‘[’ 0 -eq 1 ‘]’
  • exit 1

So, to me, it looks like the most important part of all that is:

xtrabackup: Error: cannot open /data/backups/incremental/03/xtrabackup_checkpoints
xtrabackup: error: failed to read metadata from /data/backups/incremental/03/xtrabackup_checkpoints

I have worked with the system administrator for this system and he was unable to find any indication of a problem in the storage subsystem indicating that it had gone off line or gone into a read only state or anything like that.

Has anyone had any similar experiences?

This seems to happen on all of the servers I manage where xtrabackup is installed, from time to time.

Most of the time, xtrabackup runs just fine. Unfortunately, this is ‘not good enough’. :frowning:

Any and all hints, guidance, suggestions, etc. are greatly appreciated!

/David C.

P.S. Incremental hourly backups continue to fail until the next full backup happens at 2:00AM - then the incrementals are able to find the metadata again and they pick back up.

P.P.S. I have uploaded the script that is executed to manage the backups. I am not the author, nor am I very talented with scripting. But if anyone who is talented would like to have a look, there you go. I did remove an email address and replaced it with but that’s the only change from what’s running.

System Information:

xtrabackup --version
xtrabackup version 2.0.1 for Percona Server 5.1.59 unknown-linux-gnu (x86_64) (revision id: 446)

uname -a
Linux 2.6.32-220.17.1.el6.x86_64 #1 SMP Wed May 16 00:01:37 BST 2012 x86_64 x86_64 x86_64 GNU/Linux

CentOS release 6.2 (Final)

df -h
Filesystem Size Used Avail Use% Mounted on
34G 2.7G 29G 9% /
tmpfs 5.9G 0 5.9G 0% /dev/shm
/dev/sda1 485M 68M 392M 15% /boot
/dev/sdb1 394G 238G 137G 64% /data

free -m
total used free shared buffers cached
Mem: 11912 9850 2062 0 2 26
-/+ buffers/cache: 9820 2092
Swap: 6015 784 5231

Does anyone have any ideas at all? Even if someone has a 'feeling' that it could be a problem somewhere would be great. The problem is still happening and we still don't have any more information. Thank you very much for your consideration. /David C.