Galera/Percona XtraDB Cluster (PXC) for MySQL is a hot thing right now and some users jump right in without enough testing. Consequently, they’re more likely to either suffer failure or issues that prevent them from moving forward. If you are thinking of migrating your workload to Percona XtraDB Cluster, make sure to go through these basics.

log_slave_updates is REQUIRED

You need to have log_slave_updates enabled on the cluster node acting as async slave for replicated events from the async master to be applied to the other nodes, that is if you have more than one PXC node. This is because before Galera can create writesets for the replicated events, binlog events must be generated for the transactions first. Under …

April 26, 2013 By Severalnines

This post shows you how to move from a single instance Drupal/MySQL to a multi-server environment. A well designed multi-server deployment not only allows Drupal to scale, but will also enhance redundancy by removing single points of failure. Components used are Apache, PHP, csync2, lsyncd, Keepalived, HAproxy, MySQL Galera Cluster and ClusterControl.

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Below are the slides from my last talk at this Percona Live Worldwide MySQL Conference. The idea for this talk was proposed by my co-presenter Massimo Brignoli and goes back to a debate on this topic that went through the MySQL blogosphere during last Autumn - which in itself was sparked by an outstanding retrospective published about a MySQL failure at Github.

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One of the first things we do when preparing a client’s infrastructure for Galera deployment is see whether their schema is suitable.

• Avoiding quirks and edge cases, we can say that Galera simply requires all tables to be InnoDB and also have a PRIMARY KEY (obviously having a PK in InnoDB is important anyway, for InnoDB-internal reasons).
• We want to know about FULLTEXT indexes. With recent InnoDB versions also supporting FULLTEXT we need to check not just whether a table has such an index, but actually which engine it is.
• Spatial indexes. While both InnoDB and MyISAM can deal with spatial datatypes (POINT, GEOMETRY, etc), only MyISAM has the spatial indexes.

Naturally, checking a schema in the server is more effective than going through other sources and possibly missing bits. On the downside, the only viable way to get this info out of MariaDB is INFORMATION_SCHEMA, but because of the way …

Good morning Percona Live visitors! Attached to this post you can find a spreadsheet (both LibreOffice or Excel, as you prefer) that you can use towards the end of my tutorial. I've also attached the slides so you can download a copy of them.

We were delighted last week to find out that we’d been named one of the ‘2013 Top 100 Europe’ winning companies by the Red Herring editorial team. Congratulations to all companies involved!

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We were delighted last week to find out that we’d been named one of the ‘2013 Top 100 Europe’ winning companies by the Red Herring editorial team. Congratulations to all companies involved!

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I wanted to do some experimentation with Percona XtraDB Cluster (Galera) and I didn't want to use virtual machines. I'm already using MySQL Sandbox for many other projects so that's the natural choice.

I've downloaded the tarball for Percona XtraDB Cluster 5.5.29 and I've extracted it to ~/opt/mysql/5.5.29-pxc.

Then I've installed 3 nodes:
make_sandbox 5.5.29-pxc -- --sandbox_port 4551 \
--sandbox_directory msb_5_5_29-pxc01 

make_sandbox 5.5.29-pxc -- --sandbox_port 4552 \
--sandbox_directory msb_5_5_29-pxc02 

make_sandbox 5.5.29-pxc -- --sandbox_port 4553 \
--sandbox_directory msb_5_5_29-pxc03 

But when I try to start a node this error happens:
130327 14:21:03 [Note] WSREP: wsrep_load(): loading provider library '/home/dvee
den/mysql/5.5.29-pxc/lib/libgalera_smm.so'
130327 14:21:03 [ERROR] WSREP: wsrep_load(): …

As alway with new technology there is always different approaches regarding the adoption. You can try to use the bleeding edge features or start with a very standard configuration. My personal advise to new users is to start with the most basic configuration.

This allow you to get familiar with the fundamentals : - how [...]

After some final testing and polishing, the MariaDB project and Codership are pleased to announce the release of MariaDB Galera Cluster 5.5.29. This is a Stable (GA) release. MariaDB Galera Cluster links:

• Release Notes
• Changelog
• Downloads
• APT and YUM …