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Including ODROID-HC2 Nodes in My Ceph Cluster

I built a Ceph Luminous cluster containing seven ODROID-HC2 nodes. This cluster also contains some x86 VMs running on my hypervisor.

I use this cluster mainly as a Ceph playground.

For Ceph use I definitely did not want to mess about with serial console on the ODROID-HC2 (there are 7 nodes to install, there could be more). The instructions include getting rid of the need for serial console during first boot.

Ansible and Sailfish OS

Since I seem to set up new Sailfish OS devices at least once a year (because I got myself a new toy) and I am lazy, I set up my current SailfishOS device, a Gemini PDA, up to work with Ansible.

These are my notes on using Ansible with my Gemini PDA running Sailfish OS 3.0.1.14

Fedora on the ODROID-HC2

This blog post is about installing Fedora 29 on an ODROID-HC2 (from a Fedora 29 x86_64 workstation).

The aim is to get the ODROID in a state where one can ssh as root to the host.

Both initial setup over serial and installing without using a serial console are described.

Windows 10 under KVM

These are my notes on installing Windows 10 Professional (English International) in a VM on a KVM libvirt hypervisor running on CentOS 7.

These notes also apply to Fedora and Red Hat Enterprise Linux 7 (RHEL7)

IPMI hardware watchdog with RHEL 7 / CentOS 7

introduction

My new server has IPMI which includes a watchdog timer.

Since I regularly get told that hardware watchdogs are no fun to set up, I’ll record my setup steps for an IPMI watchdog here. This document is not about watchdogs in general, but rather specifically on how to use an IPMI watchdog on a recent Red Hat based distribution.

set fan thresholds on my Super Micro H11DSi-NT

The Super Micro remote management webUI is nice and even offers KVM with HTML5. But I much prefer using vendor agnostic IPMI directly instead of a vendor specific tool like iDRAC, iLO, etc.

These are my notes on setting fan thresholds via IPMI for my H11DSi-NT motherboard.

TPM to feed random number generator

One of the uses of a TPM is to feed /dev/random on your linux box. I will not go into the political implications of TPM.

See also Matt Domsch’s blog.

Those still running RHEL5/CentOS5, be sure to have rng-utils-2.0-4 or later and kernel-2.6.18-238.el5 or later.

Some of the following steps are specific to my HP ProLiant MicroServer, but most will apply to any modern linux and HW (one would prefer the TPM to be an integral part of the motherboard as opposed to a module).