Advanced Linux, macOS, *BSD, and Unix-like tutorial {Q & A} for developers, sysadmins, and IT security folks. You can get the latest tutorial using the RSS/XML feed or weekly newsletter.
When working with FreeBSD and ZFS, you will run into ZFS cache size problems. Not all FreeBSD servers are file servers. Some servers act as backup servers. Others might run Linux and Windows VM where you want those guest VMs to manage their own caching. It would help if you had tons of RAM for ZFS, but you may not have that luxury in real life. This page explains how to set up ZFS arc size on FreeBSD to work with less RAM to avoid the computer running out of memory in the kernel. [continue reading…]
Typically, we apply firmware updates to fix a security issue and enhance SATA/PCIe/NVMe solid-state (SSD) drive performance. Failing to install available updates may lead to vulnerable SSD. This quick guide explains how to update Samsung SSD firmware on Linux without using Windows operating system. [continue reading…]
Bhyve (“BSD hypervisor”) is a free and opensource hypervisor for FreeBSD. We can use Bhyve to run Linux, Windows, and *BSD guest operating system as a virtual machine. Let us see how to install Linux VM using Bhyve on FreeBSD host operating system along with ZFS and bridged networking. [continue reading…]
How do I display dropped packets per interface on Linux operating systems from the command line option? How can I determine why a Linux server is dropping packets? [continue reading…]
How do I install and set up WireGuard VPN server on an Alpine Linux cloud server? How can I configure Alpine Linux as the WireGuard VPN server? How can I configure snat to route all VPN traffic on my Alpine Linux? [continue reading…]
I followed your Ubuntu LXD tutorial, and I noticed LXD automatically created firewall and NAT rules. Is there any way to disable this feature? I want to manage a firewall using custom rule sets. How can I disable firewall and NAT rules on the LXD bridge under Linux? [continue reading…]
Alpine Wall (Awall) is an easy to use interface to iptables for Alpine Linux users. While iptables and ip6tables is an excellent command, it can be challenging for new Alpine Linux users. The awall tool has easy to follow high-level concepts such as zones, limits, policies, and a single source for both IPv4 and IPv6. This tutorial will show you how to set up a firewall with Awall on Alpine Linux. [continue reading…]
