If you do a quick web search about UUIDs and MySQL, you’ll get a fair number of results. Here are just a few examples:
Some say that the best password is the one you don’t have to remember. That’s possible with MySQL, thanks to the auth_socket plugin and its MariaDB version unix_socket.
Neither of these plugins is new, and some words have been written about the auth_socket on this blog before, for example: how to change passwords in MySQL 5.7 when using plugin: auth_socket. But while reviewing what’s new with MariaDB 10.4, I saw that the unix_socket now comes installed by default and is one of the authentication methods (one of them because in MariaDB 10.4 a single user can have more than one authentication plugin, …
[Read more]Starting with the experimental release of Percona XtraDB Cluster 8.0, we have made changes to the SST process to make the process more robust and easier to use.
Support for mysqldump was deprecated starting with PXC 5.7 and has now been completely removed.
MySQL 8.0 introduced a new Redo Log format that limited the use of rsync while upgrading from PXC 5.7 to 8.0. In addition, the new Galera-4 also introduced changes that further limits the use of rsync.
The only supported SST method is xtrabackup-v2.
The required …
The problem
In PXC 5.6 and 5.7, when using xtrabackup-v2 as the SST method, the DBA must create a user with the appropriate privileges for use by Percona XtraBackup (PXB). The username and password of this backup user are specified in the wsrep_sst_auth variable.
This is a problem because this username and password was being stored in plaintext and required that the configuration file be secured.
The PXC 8.0 solution
(This feature is still under development and may change before PXC 8.0 GA)
Because the wsrep_sst_auth is only needed on the donor side to take a backup, PXC 8.0 uses an internal user (created specifically for use by PXC) with a randomly generated password. Since this user is only needed on the donor, the plaintext password is not needed on the joiner …
[Read more]Percona is happy to announce the first experimental binary of Percona XtraDB Cluster 8.0 on October 1, 2019. This is a major step for tuning Percona XtraDB Cluster to be more cloud- and user-friendly. This release combines the updated and feature-rich Galera 4, with substantial improvements made by our development team.
Improvements and New Features
Galera 4, included in Percona XtraDB Cluster 8.0, has many new features. Here is a list of the most essential improvements:
In a previous post, I showed you how to compile Percona Mysql 5.7 on Raspberry PI 3. Now, I’ll show you how to compile and run the latest version of Percona XtraDB Cluster 5.7.26.
We will need at least 3 RaspberryPi 3 boards, and I recommend you use an external SSD drive to compile and use as MySQL’s “datadir” to avoid the stalls associated with the microSD card, which will cause PXC to run slow.
In this post, we are going to run many OS commands and configure PXC. I recommend having minimal knowledge about PXC and Linux commands.
How to install CentOS
Download the centos image from this link …
[Read more]If you have been around MySQL for any length of time, you are probably aware that choosing the correct data types and optimizing your schema are actually important tasks. A few years back at Percona Live 2016, I gave an introductory talk on schema review and optimization. Here’s the video:
I was thinking about that talk in the context of some of my current clients. Though I had worked on extremely large database deployments during my earlier tenure at Percona, it was often more of an outlier. Now, working as a Technical Account Manager with our largest clients, it is much more common.
The Fundamental Problem
I’d like to expand my thoughts on the “choosing the smallest data type you can” principle from my 2016 slides through the lens of a few of my 2019 …
[Read more]Percona is happy to announce the release of Percona XtraDB Cluster 5.7.27-31.39 on September 18, 2019. Binaries are available from the downloads section or from our software repositories.
Percona XtraDB Cluster 5.7.27-31.39 is now the current release, based on the following:
All Percona software is open-source and free.
Bugs Fixed
Percona is glad to announce the release of Percona XtraDB Cluster 5.6.45-28.36 on September 17, 2019. Binaries are available from the downloads section or from our software repositories.
Percona XtraDB Cluster 5.6.45-28.36 is now the current release, based on the following:
All Percona software is open-source and free.
Bugs Fixed
To set correct system variable values is the essential step to
get the correct server behavior against the workload.
In MySQL, we have many System variables that can be changed at
runtime, and most of them can be set at the session or global
level.
To change the value of a system variable at the global level in the past, users needed to have SUPER privileges. Once the system variable value is modified as global, the server will change this behavior for the session, and obviously as global scope.
For instance, one of the most commonly adjusted variables is probably max_connections.
If you have max_connection=100 in your my.cnf or as the default value, and during the day as DBA you notice that it is not enough, it is easy just to add new connections on the fly with the command:
SET GLOBAL …[Read more]
