Linux – scp transfer files (passwordless) between systems

SSH (Secure SHELL) is a network protocol that is used to login into remote servers for execution of commands and programs. It is also used to transfer files from one computer to another computer over the network using secure copy (SCP) Protocol. Let’s see how to automate, passwordless, using Public/Private keys, file transfers between systems. Read More …

Ubuntu 18.04 – Restart network

Here are shown several ways how to restart networking from command line as well as from Graphical User Interface (GUI) on Ubuntu 18.04 Bionic Beaver distribution. Read More …

CentOS / RHEL 7 / Debian – Disable IPv6

If network troubleshooting leads you to believe there’s an issue with IPv6, you may need to shut down that protocol on your Linux machines. Since some hardware doesn’t take advantage of IPv6 (and most admins are still working with IPv4), a temporary and easy solution is to disable IPv6. Read More …

CentOS / RHEL 7 – Regenerate UUID for Network Cards (Physical and Virtualized Environments)

Usually, when cloning VMs on virtualized systems (Hyper-V or VMware, for example) an issue could occur related to vNICs: a vNIC could be renamed and so no more the same of the old VMs (obviously). Read More …

Linux – Make immutable a file

The chattr command is used by system administrators to restrict the users from changing a file in a particular way or even the administrator can by mistake delete a critical file because of a mis-typed command. But if the immutable flag is set, these mistakes can be avoided. Read More …

MacOS – Edit hosts file

If you are setting up a new web server or another device that’s going to be connected to the internet and you want to put it through its paces before it’s live, or if you’re having trouble with spyware and adware networks, there’s an invisible file on your Mac that can help. It’s called the hosts file, and this is how to use it. Read More …

Ubuntu 16.04 LTS Server – Configure Static IP Address

Send Us a Sign! (Contact Us!) Show More Info This article has total words. (Including header) Ubuntu 16.04 has been Read More …

Enable EPEL Repository (RHEL/CentOS 7.x/6.x/5.x)

EPEL (Extra Packages for Enterprise Linux) is open source and free community based repository project from Fedora team which provides 100% high quality add-on software packages for Linux distribution including RHEL (Red Hat Enterprise Linux), CentOS, and Scientific Linux. Read More …

Postfix – SMTP E-Mail Relay for Office 365

Postfix is a flexible mail server that is available on most Linux distribution. Though a full featured mail server, Postfix can also be used as a simple relay host to another mail server, or smart host. This tutorial will describe how to configure Postfix as a relay through Office 365 service, so using Exchange Online. Read More …

Managing Uploads, Timeouts and PHP Limits in Nginx and Apache

There are software likes Apache, Nginx, PHP, and phpMyAdmin have multiple configuration settings that define and set limits to: Memory Usage (Allocation), PHP Script Run Times, Upload File Sizes. Read More …