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RunningLow – A free PowerShell script to check for low disk space and send e-mail to System Administrators

Today I would like to share with our readers RunningLow, a simple yet effective PowerShell script I coded a while ago to get to know when one of my servers is running low of disk space.

Whoever works with physical and/or virtualized Windows Servers is well aware of the importance of keeping this constantly under control: as soon as a server runs out of disk space it will be unable to fullfill a number of tasks, such as: create temporary files, store data on a database, performing system maintenance / backup / updates, create or update web sessions – assuming they are handled through I/O – and so on. Things can be even worse for those servers who host DBMS services such as MySQL and MS-SQL, as the sudden I/O unavailability could cause non-trivial damages to indexes, filesystem-based tables and data integrity.

The main purpose of RunningLow is to prevent all that: it will check one or more local and/or network drives to see if their available free space went under a certain quota, and send a customizable alert to one or more e-mail addresses if that’s the case. I know, there are A LOT of admin suites and maintenance software that could be easily configured to the same thing: even Piriform’s CCleaner PRO does that! However, if you don’t have the money, the time or the amount of system resources required to install these apps, you might find out that this lightweight alternative could be worth a shot.

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How to fix “MySQL server has gone away”, “Packets out of order” and similar MySQL connection errors

If you’re a fond MySQL and/or MariaDB user you most certainly experienced at least one of these common errors:

MySQL server has gone away

Error reading result set’s header

Error executing query

MySQL server has gone away for query

2006, MySQL server has gone away

Packets out of order. Expected X received Y. Packet size=Z

… and so on. You can find these warnings basically anywhere, as they are usually written in the log files of the applications, tools and services that try to connect to your database and fail: however, in most scenarios, they are firstly noticed by the zealous System Administrator inspecting the PHP error log file (or the Joomla or WordPress counterpart) while trying to understand why his beloved web site or service isn’t working like it should.

That said, let’s try to understand the underlying cause and see what we can do to overcome them.

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WordPress – How to redirect all posts in one or more Categories, having one or more Tags or other custom conditions

Being able to redirect a post to another URL is a common need of any WordPress-based Web Master: there are a number of good reasons for doing that, such as: splitting your blog, moving a post from a website to another or to a sub-domain, and so on. Luckily enough, there are a lot of good plugins that can help you to do that, such as:

… and so on.

Unfortunately, most of them are either working with an SourceURL > RedirectURL static list or by adding a widget in the Edit Post page where you can insert the target redirect URL and some additional parameters, such as the redirect type (301 or 302).

What if we need to redirect all posts matching a certain condition? Here are some examples:

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ASP.NET Core: Cloud-ready, Enterprise Web Application Development – The Book

After some weeks of delay due to technical reasons the Learning Path edition of my ASP.NET Core and Angular book is finally out throughout the Amazon (and non-Amazon) marketplaces all over the world. The name is ASP.NET Core: Cloud-ready, Enterprise Web Application Development and it comes as part of the Packt Book’s Learning Path series: each of these paths features a different course for readers to give them a one-stop learning experience with different technologies. Needless to say, the course is about a full-stack programming experience with ASP.NET Core, using modern client-side frameworks (such as Angular) for the GUI part.

Here’s the updated cover:

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How to fix the “No executable found matching command dotnet-ef” error in Visual Studio with .NET Core

If you’ve stumbled upon this post it probably means that you’re trying to use Entity Framework Core in a .NET Core Visual Studio project with the dotnet ef CLI or Powershell command, which gives you the following error:

No executable found matching command “dotnet-ef”

This can be a nasty issue due to the fact that the framework gives little or no info, thus it’s not easy to understand what it actually lies under the hood. Luckily enough, there are a few things you can try that will most likely help you to fix that for good.

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