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Security improvements in MySQL 5.7

If you have a look on the last mysql 5.7.4 version or later you will probably see that there are several security improvements. The list of added security features and improvements can be seen on the following page: http://dev.mysql.com/doc/refman/5.7/en/mysql-nutshell.html

There are three main improvements that are shortly described in this blog:

1. Nonempty plugin column
2. Password lifetime policy
3. mysql_install_db secured

 

Nonempty plugin column

As of MySQL 5.7.2, the server requires account rows in the mysql.user table to have a nonempty plugin column value and disables accounts with an empty value. The following error will occor when trying to connect with user having empty plugin colum:

 

2014-11-30T10:41:04.943384Z …

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It does not matter if Aurora performs 1x or 10x MySQL: it _is_ a big thing

I spent the last 4 years at SkySQL/MariaDB working on versions of MySQL that could be “suitable for the cloud”. I strongly believed that the world needed a version of MySQL that could work in the cloud even better than its comparable version on bare metal. Users and administrators wanted to benefit from the use of cloud infrastructures and at the same time they wanted to achieve the same performance and overall stability of their installations on bare metal. Unfortunately, ACID-compliant databases in the cloud suffer from the issues that any centrally controlled and strictly persistent system can get when hosted on highly distributed and natively stateless infrastructures.
In this post I am not going to talk about the improvements needed for MySQL in the cloud - I will tackle this topic in a future post. Today I'd like to focus on the business side of RDS and Aurora. 
In the last 4 years I had endless discussions over …

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Log Buffer #399, A Carnival of the Vanities for DBAs

This Log Buffer Edition brings some freshly picked blog posts right out of the gardens of Oracle, SQL Server and MySQL.

Oracle:

Suppose you have a process A that you want to run faster. This process doesn’t commit (much), so it doesn’t wait on log file sync. However, there is another multi-threaded process, B, that commits very frequently, and spends a lot of time on “log file sync”.

New Solaris 11 CPU package to install and track CVE security fixes.

Upgrade/Migrate/Consolidate to Oracle 12c and Parallel Multitenant Upgrade Internals.

CVE metadata in Solaris …

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Recover Lost MySQL data with mysqlbinlog point-in-time-recovery example

Backup ... backup... Backup... but of course.. you also need to monitor and test those backups often otherwise they could be worthless.  Having your MySQL binlogs enabled can certainly help you in times of an emergency as well.  The MySQL binlogs are often referenced in regards to MySQL replication, for a good reason, they store all of the queries or events that alter data (row-based is a little different but this an example). The binlogs have a minimal impact on server performance when considering the recovery options they provide.


[anothermysqldba]> show variables like 'log_bin%';
+---------------------------------+--------------------------------------------+
| …

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Oracle AVDF - Database Firewall Policies

The successful deployment of a Database Firewall depends on an effective policy. Oracle AVDF includes preconfigured firewall policies as described in the Firewall Policy page in the Policy tab of the Audit Vault Server console.

These include policies that log all SQL statements, or log only unique SQL statements. In addition, the Database Firewall policy editor enables you to design your own policies quickly and efficiently.

Policy rules can depend on any combination of the SQL statement type, name of the database user, IP address of the database client, operating system user name, client program name, or any exceptions you specify.

 

First policy and global concept

1. Log in to the Audit Vault Server console as an auditor, and click on the Policy tab:

 

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Full table scans and MySQL performance

High season is coming, how do you make sure that MySQL will handle the increased load? Stress tests could help with that, but it’s not a good idea to run them in a production environment. In this case Select_scan, Select_full_join and other MySQL counters could quickly give you an idea of how many queries are not performing well and could cause a performance degradation as the load goes up.

Select_scan from SHOW GLOBAL STATUS indicates how many full table scans were done since last MySQL restart. Scanning the entire table is a resource intensive operation. It also forces MySQL to store unnecessary data in the buffer pool, wasting memory and IO resources.

Full scan of a tiny table would be quite fast so missing indexes could stay invisible until the load rises or the dataset grows up. This could also be the case for developers who work with too small data sets on their dev boxes. To prevent performance issues all newly added …

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MySQL benchmarking: Know your baseline variance!

Often enough I find MySQL benchmark results where the difference between results is 1% or even less and some conclusions are drawn. Now it is not that 1% is not important – especially when you’re developing the product you should care about those 1% improvements or regressions because they tend to add up. However with such a small difference it is very important to understand whenever this is for real or it is just the natural variance for your baseline test.

Take a look at this graph:
Click the image for a larger view)

 

This is the result for a simple in-memory, read-only “select by primary key” SysBench benchmark on dedicated physical hardware that is otherwise idle, simple 1 socket system. I tried to stabilize it as much as possible, for example …

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Nasty MySQL Replication Bugs that Affect Upgrade to 5.6

There were two nasty MySQL replication bugs in two different 5.6 releases that would make it difficult to upgrade slaves to MySQL 5.6 while still connected to MySQL 5.5 master. The first of those bugs is MySQL bug 72610 which affects 5.6.19. Essentially this bug is triggered when the table structure on the slave is different from the table structure on the master which leads to unnecessarily large amount of RAM usage while replicating events that affect that table. The amount of RAM used would generally be more noticeable when the replicated transaction consists of thousands of RBR events. The most common way this affects how we upgrade a replication hierarchy, is when we have the master running MySQL 5.5 and the slave running MySQL 5.6 and we have transactions involving DATETIME column(s). Tables with DATETIME columns will have different underlying structure when created on MySQL 5.5 versus when created on MySQL 5.6. Ideally you would avoid creating …

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Comment on Monitoring and Managing Amazon RDS Databases using MySQL Workbench by Fix Rds Error 1050 Windows XP, Vista, 7, 8 [Solved]

[…] Monitoring and Managing Amazon RDS Databases using MySQL … – May 17, 2012 · Last couple of week I was looking for an easier approch to manage the Databases created on Amazon RDS instances. I had to run through a tedious set of …… […]

Nasty MySQL Replication Bugs that Affect Upgrade to 5.6

There were two nasty MySQL replication bugs in two different 5.6 releases that would make it difficult to upgrade slaves to MySQL 5.6 while still connected to MySQL 5.5 master.

The first of those bugs is MySQL bug 72610 which affects 5.6.19. Essentially this bug is triggered when the table structure on the slave is different from the table structure on the master which leads to unnecessarily large amount of RAM usage while replicating events that affect that table. The amount of RAM used would generally be more noticeable when the replicated transaction consists of thousands of RBR events.

The most common way this affects how we upgrade a replication hierarchy, is when we have the master running MySQL 5.5 and the slave running MySQL 5.6 and we have transactions involving DATETIME column(s). Tables with DATETIME columns will have different …

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