How to install Haproxy, Letsencrypt, Varnish cache and Nginx tutorial

Actually I won’t get into details with Varnish and Nginx configuration because it really depends on your particular case. But it should be pretty straight forward as installing default packages:

apt install varnish
apt install nginx

I’m using port 443 for SSL services, so HAProxy is using this one. It also uses HTTP port 80 and redirects that to https. Everybody knows that Haproxy is stable and quick in jobs it does and that’s load balancing and proxying traffic. In our case, we are going to use it for SSL termination and forward traffic to Varnish which is going to occupy port 6081 (default). And Nginx will use port 8080 because it’s the final destination in our setup. Varnish should cache most of the web content and hopefully put our dedicated server’s CPU at ease most of the time and leverage quite slow CPU to a large amount of RAM (128GB).

In case of traffic increase we can easily balance our traffic to other servers behind Varnish,  because Varnish can play a load-balancing role as well.

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Why is Google trying to kill User Generated Content?

The core rule of capitalism is to continually look for new ways to gain capital. Profit comes before ethics, even before the future of humanity and the existence of life on the planet. Some recent-born corporations vowed not to do evil. Some still think they do not do evil. A while ago, twenty-first century tech-giants came out of nowhere — or rather, out of garages or college basements. In most cases, they began as passionate, bright, juvenile, and non-toxic minds, whose work and passion changed the planet for good. Some of them made remarkable achievements. Continue reading “Why is Google trying to kill User Generated Content?”

Difference between htmlspecialchars_decode and html_entity_decode

There are quite a few similar functions in PHP. Some of them are almost identical like echo and print and some have subtle differences which are not obvious at the first glance. We can put htmlspecialchars_decode and html_entity_decode in this category. There is a lot of confusion between notions of HTML special characters and HTML entities so let’s look into the difference.

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How to copy file with SCP from one server to other without password

Sometimes we will need to automate file copying between our servers. For example, our shell script might need to copy the backup from time to time and we don’t want to provide the password in the clean text format. So what we can do about this?

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Multiple MySQL instances on one server

When you enter the field of multiple MySQL instances on one physical server you might run into the trouble. Lack of documentation, cryptic bugs, and insane settings is something you need to get used to. I almost quit a few times in the process and only my habit of trying unusual things when everything logical failed kept me up to the solution.

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PHP – What is the difference between single and double quotes?

Difference between single and double quotes in PHP can be confusing. Moreover, it can lead to unexpected results, so it’s better to get familiar with it so you can avoid bugs.

Let’s dive into the details…

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How many CPU cores do I need?

In the 3rd installment of the Beginners guide to programming, we will explore Central Processing Unit (CPU) and its role in the computer system and programming. I hope that you remember everything from first and second level programming guide. If not, you can refresh your memory before you jump into this one.

We will start exploring CPU role from the perspective of simple question many people are asking these days which is: How many CPU cores do I need?

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Why is my computer or phone so slow? – part 2

Welcome to the level 2 of computer and programming guide. Remember all from level 1 guide for programmers?

The answer to the question from the title could be that you have RAM issues. RAM is the main memory of your computer or phone and it seems that your apps are eating to much RAM. Your whole operating system (Android, iOS, Windows) is slow because it requires more RAM but how it’s possible when you uninstalled some apps but nothing much is changed? It’s still slow.

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Beginners guide to programming – part 1

This series is meant to gradually introduce programming to the total beginners. And I mean like really total, like my father or mother which are actually using their computer without having the smallest clue how it works. As a matter of fact if the operating system freeze they may be able to restart the computer and that’s where their troubleshooting knowledge ends. Don’t get me wrong, restarting operating system helped me numerous times and it’s always one of the first choices I made in the path of troubleshooting.

However, if your plan is to become developer/ programmer you need to expand your knowledge of computer inner workings and I can assure you it’s more interesting than you might think. And it’s easy, at least to the level you need. Let’s begin …

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