Using the pressure stall information interface in kernel 4.20

Fedora 29 now has kernel 4.20 available and it has lots of new features. One of the more interesting and easy to use features is the pressure stall information interface. Load average We’re all familiar with the load average measurement on Linux machines, even if the numbers do seem a bit cryptic: $ w 10:55:46 up 11 min, 1 user, load average: 0.42, 0.39, 0.26 The numbers denote how many processes were active over the last one, five and 15 minutes.

Running Home Assistant in a Docker container with a Z-Wave USB stick

The Home Assistant project provides a great open source way to get started with home automtion that can be entirely self-contained within your home. It already has plenty of integrations with external services, but it can also monitor Z-Wave devices at your home or office. Here are my devices: Monoprice Z-Wave Garade Door Sensor Aeotec Z-Stick Gen5 (ZW090) Fedora Linux server with Docker installed Install the Z-Wave stick Start by plugging the Z-Stick into your Linux server.

Allow a port range with firewalld

Managing iptables gets a lot easier with firewalld. You can manage rules for the IPv4 and IPv6 stacks using the same commands and it provides fine-grained controls for various “zones” of network sources and destinations. Quick example Here’s an example of allowing an arbitrary port (for netdata) through the firewall with iptables and firewalld on Fedora:

iptables iptables -A INPUT -j ACCEPT -p tcp –dport 19999 ip6tables -A INPUT -j ACCEPT -p tcp –dport 19999 service iptables save service ip6tables save ## firewalld firewall-cmd –add-port=19999/tcp –permanent In this example, firewall-cmd allows us to allow a TCP port through the firewall with a much simpler interface and the change is made permanent with the –permanent argument.

How to thrive at a technical conference

I’m at the 2018 Red Hat Summit this week in San Francisco and I am enjoying the interactions between developers, executives, vendors, and engineers. It’s my seventh Summit (but my first as a Red Hat employee!), but I regularly meet people who are attending their first technical conference. The question inevitably comes up: “I’m so tired. How do you survive these events?” One attendee asked me to write a blog post on my tips and tricks.

Reaching the fork in the road

Walt Disney said it best: We keep moving forward, opening new doors, and doing new things, because we’re curious and curiosity keeps leading us down new paths. The world of technology is all about change. We tear down the old things that get in our way and we build new technology that takes us to new heights. Tearing down these old things can often be difficult and that forces us to make difficult choices.