The latest from the MySQL community

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 …

Previous episodes:

• MySQL replication monitoring 101

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 …

how to use percona-tookit to verify mysql data

Read this PDF : mysql_checksum

Previous episodes:

• MySQL replication monitoring 101

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 fast …

Introduction: where we standPrevious episodes:

• MySQL replication monitoring 101

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 as …

In the theoretical part of this series, we have seen the basics of monitoring. In that article, though, we have barely mentioned the new tools available in MySQL 5.7 and MariaDB 10. Let’s start from something that has the potential of dramatically changing replication as we know it.
Crash-safe tables and Global transaction identifiers in MySQL 5.6 and 5.7Global transaction identifiers (GTID) is a feature that has been in my wish list for long time, since the times I was working with the MySQL team. By the time I left Oracle, this feature was not even in the plans.
When MySQL 5.6 was first disclosed, the biggest improvement for replication was the introduction of crash-safe tables (see Status persistence in …

The latest MySQL Sandbox, version 3.0.66 is out. It has a few new features (as always, when I find myself doing the same thing many times, I script it) and improved support for latest releases of MySQL. You can now install, among other versions, MySQL 5.7.8 and MariaDB 10.1.x

Some notable additions in this release are in the scripts that are created and customized for each sandbox. There are many of them and when one more arrives, it's easy to overlook it. So, here are the new arrivals.



./show_binlog
When I am troubleshooting replication behavior, I often need to inspect the latest binary log. The sandbox has a shortcut that gives me the right version of mysqlbinlog for the deployment:

MySQL 5.7 comes with many changes. Some of them are better explained than others.

I wanted to see how many changes I could get by comparing SHOW VARIABLES in MySQL 5.6 and 5.7.
The most notable ones are:

• binlog_format: the default is now ROW. This variable affects the format of the binary log, whether you use it as a backup complement or for replication, the change means bigger binary logs and possibly side effects.
• …

Why Multi source replication is required?

MySQL has limitation of not allowing to replicate multiple DB’s from different master host on a single slave. MySQL replication had a limitation, fixed with this new release, that said that one slave could have only one master. That is a limiting factor when we are designing our replication environment. There were some “hacks” to make it work, but now there is an official way.

What is multisource replication?
MySQL Multi-Source Replication enables a replication slave to receive transactions from multiple sources simultaneously. Multi-source replication can be used to back up multiple servers to a single server, to merge table shards, and consolidate data from multiple servers to a single server. Multi-source replication does not implement any conflict detection or resolution when applying the transactions, and those tasks are left to the …

Hi,

I think most of the DBAs experience this error in their weekly, monthly todo list. Each one follows different approach, I would like to share some tips here:

1. You should first execute “Show Slave Status;” and check the output, analyze it. Whether SQL thread has stopped or I/O thread has stopped and check respective error , It should be either SQL error or I/O error, based on that take next step.

I/O thread has stopped:

1. Check that you can reach the master host from slave hostby using ping or traceroute/tracert to reach the host.
2. Connect to Master host and check whether “Replication thread” is connected.
3. There are multiple thread state involved, you need to take action based on thread state –  …