Thanks to everyone who joined us yesterday for this live session on designing HA for MySQL led by Krzysztof Książek, Senior Support Engineer at Severalnines. The replay and slides to the webinar are now available to watch and read online via the links below.
Watch the replay:
Become a MySQL DBA - webinar series: Which High Availability solution? from Severalnines AB
Read the slides:
Become a MySQL DBA - webinar series - slides: Which High Availability solution? from …
[Read more]This post is likely gonna get less relevant when Magento 2 comes out, but I decided to put it out there any way. In my limited time working with Magento I’ve come across a couple scenario’s I wanted to touch on. Hope it’s helpful for anyone.
Let say a merchant wants a new Magento online store. Now, there are a couple scenario’s that are likely or less likely:
Loading databases on virtual systems is not as straight forward as it should be. Last time the foundation for using Ansible was set down on our quest to be able to have fully functional database servers on virtual servers automatically. But that prompted a few of you to remind me that you do not always need Ansible.
Without Ansible
You can have Vagrant do the work. Modify the vagrant file to run
a script to run a script when provisioned, such as
config.vm.provision :shell,path:
"setup.sh"
and create the setup.sh shell script.
#!/bin/bash
#
# example setup script for LAMP stack on Vagant box
sudo apt-get -y update
sudo apt-get -y install apache2 php5 libapache2-mod-php5
## Set …For every online business, there are millions of transactions happening every second including crucial revenue bearing transactions. Therefore downtime, both planned and unplanned has a cost attached to it and results in lost revenue every second. As the technology improved to meet this demand, the importance of High Availability (HA) became the focus point.
The introduction of Galera Cluster for MySQL bought true Multimaster Cluster thanks to its synchronous replication. In this article, we’ll show how using MONyog in tandem with Galera provides a simple and best-in-class High Availability solution for MySQL users.
How to register a Galera Cluster Node in MONyog
After several iterations and a long period of community
evaluation, I am happy to report I've released the newest, stable
release of the MySQL Connector/Arduino. This library is designed
to allow you to connect your Arduino via an Ethernet or WiFi
shield to a MySQL database server running on your network (or the
Internet!).
New Documentation! Best of all, I've written a reference manual
that includes examples of how to use the connector in a variety
of ways. Included in the document are advice on how to write your
sketches, troubleshooting tips, and a long FAQ compiled from the
many questions from my blogs.
Changes The only code change in this release is to fix a defect
when using the connector with the latest versions of MySQL.
Downloading the Connector To download the connector library and
the new reference manual, visit …
If you’ve wanted to see how well MySQL Fabric actually works and how easy it makes setting up replication and switching Masters & Slaves back and forth, with a sample use case of having the master stored in a USB stick, then feel free to have a look at:
http://www.slideshare.net/keithhollman5/mysql-fabric-in-a-usb
o la versión en Español:
http://www.slideshare.net/keithhollman5/mysql-fabric-en-un-usb
Please let me know what you think.
The MySQL optimizer has a well known special system
variable—optimizer_switch—which allows
control of various optimizer modes such as index condition
pushdown (ICP), batched key access, etc. One big disadvantage of
using the optimizer_switch, however, is
that changing its value is an extra step in the query execution.…
Introduction
A question frequently asked is how much latency does Galera have in geo-distributed environments. After all, snail mail can also be used for database replication, but the latency will not be acceptable.
Let’s see how Galera performs.
A Two-Datacenter Setup
We start by creating a two-node cluster using a pair of Amazon EC2 regions that are as far apart Internet-wise as it gets – Sydney and São Paulo. The underwater cable maps do not show a direct link between Australia and South America.
The ICMP round-trip time between the two regions is a steady 316 ms:
root@ip-172-31-4-77:/home/ubuntu# ping ec2-54-94-217-199.sa-east-1.compute.amazonaws.com
PING ec2-54-94-217-199.sa-east-1.compute.amazonaws.com (54.94.217.199) 56(84) bytes of data.
64 bytes from ec2-54-94-217-199.sa-east-1.compute.amazonaws.com …What about inserting data to MySQL 5.7.7-rc-debug with GTID/binary log enabled. It is OK until you hit disk full condition while inserting data. It will crash on the way and likely you will lose MySQL. Error log indicates related problem:
2015-07-29T07:20:05.865708Z 2 [ERROR] InnoDB: posix_fallocate(): Failed to preallocate data for file ./sls2/sales.ibd, desired size 4194304 bytes. Operating system error number 28. Check that the disk is not full or a disk quota exceeded. Make sure the file system supports this function. Some operating system error numbers are described at http://dev.mysql.com/doc/refman/5.7/en/operating-system-error-codes.html
2015-07-29T07:20:05.895529Z 2 [Warning] InnoDB: 1048576 bytes should have been written. Only 557056 bytes written. Retrying again to write the remaining bytes.
2015-07-29T07:20:05.905149Z 2 [Warning] InnoDB: 491520 bytes should have been written. Only 106496 bytes written. Retrying again to write the remaining …[Read more]
After installing a MySQL database server, like the one I posted earlier, if it's going to be a production environment than you should consider securing the instance by eliminating some of the basic vulnerabilities that come with a generic install. Fortunately MySQL and MariaDB already come with a tool for that purpose, called mysql_secure_installation. This program enables to perform the