The latest from the MySQL community

There will be a MySQL & Friends Devroom at the FOSDEM 2015 this year.And surprisingly my talk - not sure you can call 15 min a talk  - had been accepted. (There are other accepted talks of course.) 
It will be a dense talk about Docker/MySQL/Galera :)
We are (at least me) are going to have fun \o/ Erkan
I hope there will be an official announcement too.  

January 5, 2015 By Severalnines

Cloud storage is hot. Dropbox, Apple iCloud, Google Drive, Microsoft SkyDrive and Amazon Cloud Drive all offer cloud sharing platforms where you can store documents in the cloud and access them from all your devices. For enterprises who require full control, ownCloud is an open source solution that allows files to be stored on-premises and/or a backend cloud. 

In this blog post, we’ll show you how to deploy a high availability setup using ownCloud Community Edition. We will need to set up redundancy in each of the following layers:

• file storage
• web server
• database server
• load balancer

We will use five servers. ownCloud will run on three separate servers with MySQL Galera Cluster 5.6 and GlusterFS running on RHEL 6.5 64bit. ownCloud supports GlusterFS as primary storage. ClusterControl will be co-located …

State Snapshot Transfer (SST) is used in Percona XtraDB Cluster (PXC) when a new node joins the cluster or to resync a failed node if Incremental State Transfer (IST) is no longer available. SST is triggered automatically but there is no magic: If it is not configured properly, it will not work and new nodes will never be able to join the cluster. Let’s have a look at a few classic issues.

Port for SST is not open

The donor and the joiner communicate on port 4444, and if the port is closed on one side, SST will always fail.

You will see in the error log of the donor that SST is started:

[...]
141223 16:08:48 [Note] WSREP: Node 2 (node1) requested state transfer from '*any*'. Selected 0 (node3)(SYNCED) as donor.
141223 16:08:48 [Note] WSREP: Shifting SYNCED -> DONOR/DESYNCED (TO: 6)
141223 16:08:48 …

Background on Backup Locks

I was very excited to see Backup locks support in release notes for the latest Percona XtraDB Cluster 5.6.21 release. For those who are not aware, backup locks offer an alternative to FLUSH TABLES WITH READ LOCK (FTWRL) in Xtrabackup. While Xtrabackup can hot-copy Innodb, everything else in MySQL must be locked (usually briefly) to get a consistent snapshot that lines up with Innodb. This includes all other storage engines, but also things like table schemas (even on Innodb) and async replication binary logs. You can skip this lock, but it isn’t …

If you are automating your infrastructure deployments with Chef, then read on. We are glad to announce the availability of a Chef cookbook for ClusterControl. This cookbook replaces previous cookbooks we released for ClusterControl and Galera Cluster. For those using Puppet, please have a look at our Puppet module for ClusterControl.

ClusterControl Cookbook on Chef Supermarket

The ClusterControl cookbook is available on Chef Supermarket, and getting the cookbook is as easy as:

$ knife cookbook site download clustercontrol

This cookbook supports the installation of ClusterControl on top of existing database clusters:

• Galera Cluster
  • MySQL Galera Cluster by Codership
  …

For an online shop, the website is the cash register. It has to be open for business 24 hours a day.

As the ops person on duty, when you get a call at 3am after your website went down, your priority number one is to restore the service asap. But why can we not have our application stack automatically recover, and not have the pager wake us at all? Why do we still stick to tedious manual processes, which take up time and resources, and hinder future growth?

Infrastructure automation isn’t easy, but it’s not rocket science either, says Riaan Nolan. Riaan has been in operations for the past decade, and has built over a dozen eCommerce properties. Automation is a worthwhile investment for retailers serious about eCommerce, but deciding on which tools to invest in can be a confusing and overwhelming process.

Join us for this webinar to understand the key pain points that online retailers experience which indicate it’s time …

Thanks to everyone who attended and participated in last week’s webinar on 'Galera Cluster for MySQL vs MySQL (NDB) Cluster: A High Level Comparison'. If you missed the sessions or would like to watch the webinar again & browse through the slides, they are now available online.

In this webinar, Severalnines VP of Products, Alex Yu, who was part of the team at Ericsson who originally developed the NDB storage engine in 2001, gave an overview of the two clustering architectures and discussed their respective strengths and weaknesses: 

1. MySQL Cluster architecture: strengths and limitations
2. Galera Architecture: strengths and limitations
3. Deployment scenarios
4. Data migration
5. Read and write workloads (Optimistic/pessimistic locking)
6. WAN/Geographical replication
7. Schema changes
8. Management and monitoring …

December 8, 2014 By Severalnines

Percona XtraBackup is a great backup tool with lots of nice features to make online and consistent backups, although the variety of options can be a bit overwhelming. s9s_backup tries to make it simpler for users, it creates an easy to use interface for XtraBackup features such as full backups, incremental backups, streaming/non-streaming, and parallel compression.

Backups are organized into backup sets, consisting of a full backup and zero or more incremental backups. s9s_backup manages the LSNs (Log Sequence Number) of the XtraBackups. The backup set can then be restored as one single unit using just one command.

In earlier posts, we covered various ways on restoring your backup files …

December 1, 2014 By Severalnines

MariaDB 10 supports multi-source replication, and each MariaDB Galera node can have up to 64 masters connected to it. So it is possible to use a MariaDB Cluster as an aggregator for many single-instance MariaDB master servers.

In this blog post, we are going to show you how to setup multi-source replication with MariaDB Galera Cluster, where one of the Galera nodes is acting as slave to 3 MariaDB masters (see diagram below). If you would like to set this up with Percona XtraDB Cluster or Galera Cluster (Codership), please read this post instead.

MariaDB GTID vs MySQL GTID

MariaDB has a different implementation of Global Transaction ID (GTID), and is enabled by default starting from MariaDB 10.0.2. Multi-source replication in MariaDB works …

November 20, 2014 By Severalnines

Multi-source replication means that one server can have multiple masters from which it replicates. Why multi-source? One good reason is to consolidate databases (e.g. merge your shards) for analytical reporting or as a centralized backup server. MariaDB 10 already has this feature, and MySQL 5.7 will also support it. 

It is possible to set up your Galera Cluster as an aggregator of your masters in a multi-source replication setup, we’ll walk you through the steps in this blog. Note that the howto is for Galera Cluster for MySQL (Codership) and Percona XtraDB Cluster. In a separate post, we’ll show you how to configure MariaDB Cluster 10 instead. If you would like to use MySQL Cluster (NDB) as aggregator, then check out this blog.

Galera …