Install Archlinux on LUKS encrypted BTRFS filesystem with subvolumes

In this post I will go through the system installation. Second post will be about btrfs snapshots, namely how to create and restore snapshot.

ArchLinux installation is very well documented on Archlinux Wiki. My tutorial basically follows all the necessary steps from the wiki page with some additional configuration to achieve:

• LUKS encryption (this will be applied to all partitions except /boot)
• btrfs formatted filesystem, with use of subvolumes with flat layout

VirtualBox: shrink Clonezilla disk image

I've spent some time until I finally found out how you can not only increase the disk image but also how to shrink it.

Use case:
I had an disk backup created with clonezilla. The source disk size was 1TB and the restore disk size was 256GB. The actual data amount was around 120GB, so it would definitely fit on the smaller disk.
But with clonezilla, I wasn't able to restore it.

Bash Functions

This post contains few functions, or tips I often use, so I keep them close.

Elasticsearch: setting up watcher for FS monitoring

In this post, we'll go through components used for this case scenario and the process of setting up a watcher within elasticsearch.

Our case scenario: we have three machines running different OS (all are linux based) and we'd like to be notified when we're running low on disk space. For this we've taken advantage of running elasticsearch instance with Gold license and enabled watcher feature.

SF OS X

Android. That's the operating system which most probably runs on your mobile phone.
While this is the very common system to have nowadays, it's matured enough throughout the years and built very rich ecosystem of applications, there are a few things which I don't like on it.

The basic idea is, that if you buy something, you should own it. You should be able to disassemble it and modify it, to adjust it to your needs and most noticeably: you should be in full control of your device.

Hide Tab Bar in Firefox 57+

Finally I've found a way to hide tabs from Firefox.
I use Tree Style Tabs addons and don't need native tabs.

So here is how you can do it:

Ping-based Host Monitoring Script with Timestamps

In my previous post Server availability monitoring with email notifications I've used the same idea of monitoring. This script is a version 2.0 with some additional features:

1. If you compare old and new version, you'll notice the script was completely rewritten. It's because I wanted it to run on my synology NAS.
2. Next change is additional host states, instead of A-available and N-notAvailable I'm now using 2 additional states Going Up, Going Down. This will delay the notification about host state change and prevent frequent flapping of naughty hosts in network.
3. Last feature added is hosts UP/DOWN times in notifications; see mail notification example: