Showing entries 1 to 10
Displaying posts with tag: multi-source (reset)
MySQL Group Replication vs. Multi Source

In my previous post, we saw the usage of MySQL Group Replication (MGR) in single-primary mode. We know that Oracle does not recommends using MGR in multi-primary mode, but there is so much in the documentation and in presentations about MGR behavior in multi-primary, that I feel I should really give it a try, and especially compare this technology with the already existing multiple master solution introduced in 5.7: multi-source replication.


To this extent, I will set up two clusters using MySQL-Sandbox. The instructions for MGR in …

[Read more]
Sound advice for GTID, with caveats

During the PerconaLive conference in Amsterdam, I attended a session where I heard a good piece of advice about using GTID. It amounts to: look at SHOW SLAVE STATUS output, and if you see more than one line in the Executed_Gtid_Set field, this tells you immediately if someone has written on a slave database.
This is good advice. Let's dissect it. Here is what a regular slave looks like, when nobody has messed up with it:

*************************** 1. row ***************************
Master_Server_Id: 1
Master_UUID: 00013454-1111-1111-1111-111111111111
Master_Info_File: mysql.slave_master_info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for more …
[Read more]
MySQL usability issues for replication

In my latest series of advanced replication features, I came across several usability issues, which I would like to recap here. For each section of this list of requests, I make a wish list, with some general comments.
INSTALLATIONAs the maintainer of MySQL Sandbox, a tool that wants to facilitate the installation of …

[Read more]
MySQL replication in action - Part 4 - star and hybrid topologies

Previous episodes:

MySQL replication in action - Part 1: GTID & CoMySQL replication in action - Part 2 - Fan-in topologyMySQL replication in action - Part 3 - All-masters P2P topology
Introducing star topology.In all-masters P2P topologies, we have seen that we have a way of deploying a topology where all nodes are masters, and achieve better efficiency and stability than ring topologies. That …

[Read more]
MySQL replication in action - Part 3: all-masters P2P topology

Previous episodes:

MySQL replication in action - Part 1: GTID & CoMySQL replication in action - Part 2 - Fan-in topology

In the previous article, we saw the basics of establishing replication from multiple origins to the same destination. By extending that concept, we can deploy more complex topologies, such as the point-to-point (P2P) all-masters topology, a robust and …

[Read more]
MySQL replication in action - Part 2 - Fan-in topology

Introduction: where we standPrevious episodes:

MySQL replication in action - Part 1: GTID & Co
In the latest releases of MySQL and MariaDB we have seen several replication improvements. One of the most exciting additions is the ability to enhance basic replication with multiple sources. Those who have used replication for a while should remember that one of the tenets of the “old” replication was that a slave couldn’t have more than one master. This was The Law and there was no escape ... until now. The only way to work around that prohibition was to use circular replication, also known …

[Read more]
Multi-source Replication with MariaDB Galera Cluster

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 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 …

[Read more]
MySQL 5.6 GA one year – What is next?

MySQL 5.6 has been GA for just over a year now. See MySQL 5.6.10 Release Notes.  Congratulations on your birthday! That is quite a long time. I was using it earlier in production because it worked and could do things that 5.5 could not do, but earlier versions were to use at your own risk, and indeed if prodded incorrectly would fall on the floor. That is fair enough because they were work in progress, yet if you poked them the right way they did a very good job.  Those dev versions have been long since upgraded which is good so they do not need quite as much care and attention.

So from where I see 5.6 it works very well. One big change that has made a large difference but which I think a lot of people may not really understand or use is the …

[Read more]
Enabling MySQL Multi-Source Replication Workflows with GTIDs

The goal of this post is twofold: (i) to show the power of GTIDs and MySQL 5.6 replication infrastructure in general; and (ii) show MySQL users a way to hack multi-source replication rather painlessly and rather quickly on top of MySQL 5.6 when using the new MySQL 5.6 replication features.Multi-source ReplicationMulti-source replication is often regarded as a mean to aggregate, consolidate, different streams of data into one single server instance, a sink. In many cases the following assumptions hold:

  1. There are no conflicts between transactions from different sources/masters;
  2. Replication is asynchronous (just as it is in regular MySQL replication).

Such setups are interesting for some use cases, in particular those that are either: driven by the need to gather data …

[Read more]
Round-Robin Multi-Source in Pure SQL

With the addition of the new tables to implement crash-safe replication we also get access to replication information through the SQL interface. This might not seem like a big advantage, but it should not be taken lightly. To demonstrate the power of using this approach, I will show how to implement a multi-source round-robin replication described at other places (including our book). However, compared to the other implementations—where the implementation requires a client to parse the output of SHOW SLAVE STATUS—the twist is that the implementation is entirely done in the server, using pure SQL.

If you're familiar with replication, you know that a slave can just …

[Read more]
Showing entries 1 to 10