CentOS – Page 4 – The WP Guru

How to set the hostname on CentOS and Fedora

December 30, 2020November 9, 2015 by Jay Versluis

CentOS 7 has a nice command called hostnamectl. With it we can display the current hostname, and set any of the three types of hostname: static hostname (something like example.com) transient hostname (anything you like, assigned when using DHCP) pretty hostname (something like Jay’s MacBook Pro) By default, a CentOS installation comes back with localhost.localdomain … Read more

OS X Server vs. Parallels Desktop – Overhead Differences

October 21, 2016November 4, 2015 by Jay Versluis

Ever wondered if there’s a difference in overhead and memory usage when you’re using a VM instead of OS X directly? Here’s a comparison for website hosting.

The above graph shows the difference of hosting one of my websites for the last few days on OS X Server (in blue) that I got from Hostgator (using their HostGator Thanksgiving Deal 2016 coupon), and in a CentOS VM under Parallels Desktop 10 on the same hardware (in red).

The traffic logs show that the amount of requests and visitors has remained the same, so we can deduce that the load put on either OS X and the VM is the same. There is a little more overhead when using the VM, but not as much as I had feared: the requests have to be forwarded to another software layer after all, and that takes some CPU power.

Let’s have a look at memory next:

How to disable SSH access from everywhere except for certain IPs in CentOS 7

November 3, 2015November 2, 2015 by Jay Versluis

Here’s how to do it: firewall-cmd –zone=internal –add-service=ssh –permanent firewall-cmd –zone=internal –add-source=1.2.3.4/32 –permanent firewall-cmd –zone=internal –add-source=5.6.7.8/32 –permanent firewall-cmd –zone=public –remove-service=ssh –permanent firewall-cmd –reload This declares an internal zone with two IPs (add as many or as few as you like) and subsequently removes the SSH service from the public zone altogether. As a result, any … Read more

How to disable the user list at login on CentOS 7

August 14, 2015 by Jay Versluis

By default, CentOS 7 will display a list of all users on the system. Click on it, type in the password, and you’re in. This works well when you have a handful of users on the system. However, on systems with a lot of users, not everyone can be displayed in that list – and scrolling up … Read more

How to enable automatic user logins in CentOS 7 and GNOME

August 13, 2015 by Jay Versluis

If you’ve read my previous article about how to enable automatic logins on CentOS 6, and it sounded a little daunting, you may be pleased to hear that it’s a little easier to accomplish the same thing on CentOS 7.1. If you’re using GNOME in a single user environment, and you’re confident that nobody else … Read more

How to install Parallels Tools via the Command Line in CentOS

August 7, 2015July 24, 2015 by Jay Versluis

I like setting up barebones CentOS and other flavoured VMs on my Mac via Parallels Desktop. Trouble is, for such things like time synchronisation to work properly, something called Parallels Tools needs to be installed on each VM. This is to make sure Parallels Desktop can speak to the VM and communicate with it properly. … Read more

How to enable resuming FTP uploads in Plesk

July 17, 2015 by Jay Versluis

Plesk uses ProFTP as the default FTP server. It has a handy feature that allows file uploads to resume or append should a connection be broken during transmission. This means that partially transferred data doesn’t have to be uploaded again, it can simply be added to – potentially saving a lot of time. Although easy … Read more

How to update Plesk via the Command Line

July 2, 2017May 3, 2015 by Jay Versluis

You can update Plesk via the Web Interface (under Tools and Settings – Updates and Upgrades). However sometimes the interface times out, or browsers get confused – therefore it’s good to know that you can apply updates via the command line interface as well. In this article I’ll show you how (in Linux – I … Read more

CentOS Archives