How to setup a UFW firewall on Ubuntu 16.04 LTS server

H ow do I setup a firewall with UFW (uncomplicated firewall) on an Ubuntu Linux 16.04 LTS server to restrict traffic on my personal web-server that hosts my pictures and blogs for my family members?…

How to create RAID 10 – Striped Mirror Vdev ZPool On Ubuntu Linux

How do I create zfs based RAID 10 (striped mirrored VDEVs) for my server as I need to do small random read I/O. How can I create striped 2 x 2 zfs mirrored pool on…

PHP-fpm Too Many Open Files 24 Error (set open file descriptor limit)

I am getting the following error in my /var/log/php7.0-fpm.log file: “ERROR: failed to prepare the stderr pipe: Too many open files (24)” How do I fix this problem?   You need to set open file…

How to configure pfSense as multi wan (DUAL WAN) load balance failover router

H ow do I setup a multi-WAN load balancing and failover on pfSense router with two ADSL or cable or leased-line or FTTH (Fiber to the home) connections?   In this tutorial you will learn…

How to apply Debian security patches

I am new to Debian and confused about how to get access to the Debian security updates. How do I apply security patches to my Debian Linux server using the command line option?   If…

How to see CPU temperature on CentOS 7 and RedHat Enterprise Linux 7

I am a new sysadmin of CentOS 7 server. How do I get my CPU temperature Information on CentOS Linux 7 or Red Hat Enterprise Linux 7 server? How can I read my CPU temperature…

How to see PCI devices info on CentOS 7 and RedHat Enterprise Linux 7

I wanted to see PCI devices information on my CentOS/RHEL 7 box. But, I’m getting an error that read as, “-bash: lspci: command not found”. How do I solve this problem and see PCI devices…

How to configure a static IP address on CentOS 7 / RHEL 7

I am a new sysadmin and CentOS user. My system is configured to use DHCP. How can I switch from DHCP to static IP address configuration in a CentOS 7 desktop system? How do I…

How to make disk image with dd on Linux or Unix

H ow do I create disk image using dd command? How do I perform disk cloning from a live Linux cd for backup or recovery purpose?   You can easily use the dd command for…

How to configure Wi-fi+Lan bridged access point in pfSense firewall router

I have installed wireless mini-PCIe card for my pfSense firewall. How do I configure a bridged LAN wifi access point (AP) network and setup pfSense?   In this tutorial, I will explain how to setup…