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Displaying posts with tag: howto (reset)
dim_STAT : Collect MySQL & System stats @Linux locally

Generally you have much bigger benefit with dim_STAT when you're collecting and analyzing your data live (online). However, there maybe still many situations when this is simply not possible (due security restrictions, wide remote distance, or simply externally inaccessible hosts, etc.) -- for such cases dim_STAT has special tool EasySTAT allowing you to collect all the needed stats locally on the given machine, and then later to upload them to your dim_STAT server for post-analyze. To simplify overall setup, EasySTAT is integrated into STAT-service of dim_STAT and can be directly involved from there, also following the same rules for MySQL access and so on (e.g. if your STAT-service is already operational, then your EasySTAT will be too ;-))

The following article is explaining how to deploy and start EasySTAT

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MySQL High Availability Framework Explained – Part III: Failure Scenarios

In this three-part blog series, we introduced a High Availability (HA) Framework for MySQL hosting in Part I, and discussed the details of MySQL semisynchronous replication in Part II. Now in Part III, we review how the framework handles some of the important MySQL failure scenarios and recovers to ensure high availability.

MySQL Failure Scenarios Scenario 1 – Master MySQL Goes Down

  • The Corosync and Pacemaker framework detects that the master MySQL is no longer available. Pacemaker demotes the master resource and tries …
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MySQL Tutorial – Understanding The Seconds Behind Master Value

In a MySQL hosting replication setup, the parameter Seconds_Behind_Master (SBM), as displayed by the SHOW SLAVE STATUS command, is commonly used as an indication of the current replication lag of the slave. In this blog post, we examine how to understand and interpret this value in various situations.

Possible Values of  Seconds Behind Master

The value of SBM, as explained in the  MySQL documentation, depends on the state of the MySQL slave in general, and the states of MySQL slave SQL_THREAD and IO_THREAD in particular. While IO_THREAD connects with the master and reads the updates, SQL_THREAD applies these updates on the slave. Let’s examine the possible values of SBM during different states of the MySQL Slave.

When SBM Value is Null

  • SBM is …
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MySQL High Availability Framework Explained – Part II: Semisynchronous Replication

In Part I, we introduced a High Availability (HA) framework for MySQL hosting and discussed various components and their functionality. Now in Part II, we will discuss the details of MySQL semisynchronous replication and the related configuration settings that help us ensure redundancy and consistency of the data in our HA setup. Make sure to check back in for Part III where we will review various failure scenarios that could arise and the way the framework responds and recovers from these conditions.

What is MySQL Semisynchronous Replication?

Simply put, in a …

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Slow MySQL Start Time in GTID mode? Binary Log File Size May Be The Issue

Have you been experiencing slow MySQL startup times in GTID mode? We recently ran into this issue on one of our MySQL hosting deployments and set out to solve the problem. In this blog, we break down the issue that could be slowing down your MySQL restart times, how to debug for your deployment, and what you can do to decrease your start time and improve your understanding of GTID-based replication.

How We Found The Problem

We were investigating slow MySQL startup times on a low-end, disk-based MySQL 5.7.21 deployment which had GTID mode enabled. The system was part of a master-slave pair and was under a moderate write load. When restarting during a scheduled maintenance, we …

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Configuring and Managing SSL On Your MySQL Server

In this blog post, we review some of the important aspects of configuring and managing SSL in MySQL hosting. These would include the default configuration, disabling SSL, and enabling and enforcing SSL on a MySQL server. Our observations are based on the community version of MySQL 5.7.21.

Default SSL Configuration in MySQL

By default, MySQL server always installs and enables SSL configuration. However, it is not enforced that clients connect using SSL. Clients can choose to connect with or without SSL as the server allows both types of connections. Let’s see how to verify this default behavior of MySQL server.

When SSL is installed and enabled on MySQL server by default, we will typically see the following:

  1. Presence of *.pem files in the MySQL data directory. These are the various client and server certificates and keys that are in …
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Data Integrity and Performance Considerations in MySQL Semisynchronous Replication

MySQL semisynchronous replication provides improved data integrity because when a commit returns successfully, it’s known that the data exists in at least two places – the master and its slave. In this blog post, we review some of the MySQL hosting configurations that influence the data integrity and performance aspects of semisynchronous replication. We’ll be using InnoDB storage engine and GTID-based replication in a 3-node replica set (master and 2 slaves), which will ensure there is redundancy in the slaves. This means that if there are issues with one slave, we can fall back on the other.

Configurations Applicable to Both Master and Slave Nodes

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Calculating InnoDB Buffer Pool Size for your MySQL Server

What is an InnoDB Buffer Pool?

InnoDB buffer pool is the memory space that holds many in-memory data structures of InnoDB, buffers, caches, indexes and even row-data. innodb_buffer_pool_size is the MySQL configuration parameter that specifies the amount of memory allocated to the InnoDB buffer pool by MySQL. This is one of the most important settings in the MySQL configuration and should be configured based on the available system RAM.

In this post, we’ll walk you through two approaches of setting your InnoDB buffer pool size value, examine the pros and cons of those practices, and also propose a unique method to arrive at an optimum value based on the size of …

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MySQL InnoDB Cluster – Setting up InnoDB Cluster on Windows

One of the most requested features for InnoDB cluster has been Windows support that we have now delivered as part of the InnoDB Cluster 5.7.17 Preview Release 2. This blog post will show you how to get your InnoDB cluster running on your MS Windows 10 64bit system.…

MySQL InnoDB Cluster – A Hands on Tutorial

Traditionally, setting up high availability (HA) in MySQL has been a challenging task, especially for people without advanced knowledge of MySQL. From understanding concepts and technologies, to the tooling, specific commands and files to execute and edit, there’s a lot of things you need to know even when planning a test deployment (the Quick Start Guide for Group Replication should give you an idea).…

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