Category: Linux Administration

Linux system monitoring and statistics gathering

We will look at some Linux commands which will help us monitor system performance, gather statistics and view historical resource usage. Monitoring connections with ss command ss should be preinstalled for most modern Linux distributions Show established TCP connection ss -t Show established UDP connections ss -u Show ports listening for TCP connections ss -ltn

Backup FreeNAS ZFS Dataset to Ubuntu running ZFS

We are setting up replication of snapshots for backup purposes on FreeNAS. We setup Ubuntu server and install ZFS on it. We will use this system to receive snapshot for backup purposes. We manually generated ssh key on FreeNAS. This was done by connecting to CLI and running commands below. ssh-keygen -q -t rsa scp

Integrate FreeIPA with Windows 2016 Active Directory

In this LAB we will setup Trust based integration between FreeIPA and Windows 2016 Active Directory Forest Lab Information Windows 2016 Standard CentOS 7.5.1804 FreeIPA 4.5.4 Windows domain-win.poc.lab IPA domain-lin.poc.lab Kerberos realm names = WIN.POC.LAB ; LIN.POC.LAB Required Firewall ports TCP ports: 80, 88, 443, 389, 636, 88, 464, 53, 135, 138, 139, 445, 1024-1300

Using screen command to share session on Linux system

Lets take a look at how to share existing ssh session using command called screen. It is very useful in case where you have to show your users something remotely. First install screen program – We assume CentOS7 yum install screen System1 You can create multiple screen sessions or share existing on Create multiple screen

Using Vagrant, VirtualBox and Ansible with CentOS 7

This would be the case when you need to test playbooks locally before using Ansible to deploy them. We assume you already have installed Vagrant, Ansible and VirtualBox. Ansible is one of many provisioners integrated with Vagrant. Lets see how it works Create Vagrant box with CentOS 7 mkdir centtest cd centtest sudo vagrant init

Installing and using docker CentOS7

We will not cover what docker does and how it works. We assume you already familiar with basic concepts. We will look into basics of installing and operating docker on CentOS 7. We will be looking into CE )(Community Edition) Installation We will go over install using repositories yum install -y yum-utils device-mapper-persistent-data lvm2 yum-config-manager

Installing and using LXC Containers on CentOS 7

LXC allows us to share Linux kernel to run application in something similar to chroot environment. Lets take a look at how to install and manage LXC on CentOS 7. Containers reside in /var/lib/lxc/ directory Installation yum install epel-release yum install debootstrap perl libvirt yum install lxc lxc-templates systemctl start lxc.service systemctl start libvirtd systemctl

Install latest version of apache, mariadb and php on CentOS7

In one of out previous tutorials Install LAMP on CentOS we looked at installing LAMP on CentOS 7. Although this type if installation is fine for most of the deployments, in some cases you want to get the latest version of LAMP components. In most cases we will want to do this due to security

Mining litecoin with cpuminer

Lets look at how we can mind litecoin with cpuminer and litecoinpool. 1. Go to website and create an account. 2. Install cpuminer # apt-get update # apt-get install libcurl4-openssl-dev git # apt-get install build-essential # apt-get install autotools-dev autoconf # apt-get install libcurl3 libcurl4-gnutls-dev # apt-get install automake # mkdir /downloads # cd

Deploy AWStats on CentOS 7 to report SMTP traffic

Let’s look at deploying AWStats on CentOS 7 Mail gateway running postfix and MailScanner 1. First lets install httpd if not yet installed yum install httpd 2. In order to install AWStats we will need to install and add EPEL repository yum install epel-release 3. Now we can install AWStats yum install awstats AWStats Configuration