It is a common good practice to extend data safety by having additional measures apart from regular data backups, such as delayed slaves and binary log backups. These two options provide the ability to restore the data to any given point in time, or just revert from some bad accidents. These methods have their limitations of course: delayed slaves only help if a deadly mistake is noticed fast enough, while full point-in-time recovery (PITR) requires the last full backup and binary …[Read more]
I recently wrote a blog post describing a different way of doing Point-In-Time Recovery (PITR). If you want to know the step by step, please visit the mentioned blog post. Here is a quick summary of the approach:
- Restore the backup on the desired server
- Create a fake master
- Copy all relevant binlogs to the fake master
- Configure server from the first step as a slave from a fake master
In addition to the above steps, there is a similar approach …[Read more]
Join Percona’s, Technical Services Manager, Jervin Real as he presents Lock, Stock and Backup: Data Guaranteed on Wednesday, August 16, 2017 at 7:00 am PDT / 10:00 am EDT (UTC-7).
Backups are crucial in a world where data is digital and uptime is revenue. Environments are no longer bound to traditional data centers, and span multiple cloud providers and many heterogeneous environments. We need bulletproof backups and impeccable recovery processes. This talk aims to answer …[Read more]
Data corruption! It can happen. Maybe because of a bug or storage problem that you didn’t expect, or MySQL crashes when a page checksum’s result is different from what it expected. Either way, corrupted data can and does occur. What do you do then?
Let’s look at the following example and see what can be done when you face this situation.
We have some valuable data:
> select * from t limit 4; +---+--------+ | i | c | +---+--------+ | 1 | Miguel | | 2 | Angel | | 3 | Miguel | | 4 | Angel | +---+--------+ > select count(*) from t; +----------+ | count(*) | +----------+ | 2097152 | +----------+
One day the query you usually run fails and your application stops working. Even worse, it causes the crash already mentioned:
> select * from t where i=2097151; ERROR 2006 (HY000): MySQL server has gone away
Usually this is the point when panic starts. The error log …[Read more]
January 23, 2014 By Severalnines
Thanks to everyone who attended this week’s webinar; if you missed the sessions or would like to watch the webinar again and browse through the slides, they are now available online.
Special thanks to Seppo Jaakola from Codership, the creators of Galera Cluster, for walking us through the various scenarios of Galera recovery.
Webinar topics discussed:
- Redundancy models for Galera, NDB and MongoDB / TokuMX
- Failover & Recovery (Automatic vs Manual)
- Zooming into Galera recovery procedures
- Split brains in multi-datacenter setups
Watch the replay: