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Transforming an encrypted array from RAID 1 to RAID 6

1 Introduction Some context I have a NAS at home which runs on Debian Jessie. A NAS wouldn’t be a NAS without some storage, so I put in two disks with 4 TB each when I built it. Those two disks have actually been used in a setup with OpenMediaVault before that and already had a software-RAID on them. When migrating the disks (to Ubuntu at first) I learned about mdadm and that OpenMediaVault uses it. read on »

Install Ghost on an Arch VPS

I recently got myself a small VPS from Hetzner to play around with. Using their ‘rescue’ function you can mount different installer images in the virtual disc drive and install the system via VNC or web console. They provide an Arch installer too, so I chose that. I set up a very barebones system on a btrfs partition and with an nginx webserver. To me, Arch seemed like an interesting choice for a webserver and so I cloned my nginx config from my nas and began to go through all the directives again and tidy up all the configs in the process, making as much as possible a global directive inside the http { } block. read on »

OpenSSH + OATH-TOTP

I dug a little further after my last post and stumbled upon this excellent blog post. It turns out that using the libpam-oath module for two-factor authentication is a lot easier than the challenge-response module and it works rather fabulously. I will document the steps I took here. Again, all credit goes to the author of that blog post above - I mainly followed his explanations and links. What we are going to do We want to enable two-factor authentication when logging in via ssh. read on »

OpenSSH + YubiKey HMAC-SHA1 challenge-response

_First off: this does not work as I wanted it to work .. it has some interesting implications though._ The idea I am using a YubiKey NEO for various things. It holds my PGP keys in its secure element and has the YubiKey slots configured to use HMAC-SHA1 challenge response and static password. You can for example unlock your KeePass(X) database using OATH-HOTP or the challenge-response mechanism. The idea was to use the PAM module in its challenge-response mode for authentication during SSH logins. read on »

Freifunk VLAN

Freifunk explained The vision of Freifunk is the establishment of free networks, the democratization of communication media and the promotion of local social structures. Basically, if you want to participate in a Freifunk community, you take a router capable of running OpenWRT and flash it with a special community-flavored version of OpenWRT based on Gluon. If there are other Freifunk nodes in reach, your router will mesh with them and connect you to the network. read on »