Category: Linux

First steps with smartcards under Linux and Android — hard, but it works

July 16th, 2015, 2 Comments

Well this has been an interesting project. It all started with a need to get better password storage at work. We wound up looking heavily at a GPG-based solution. This prompted the question: how can we make it even more secure? Well, perhaps, smartcards. The theory is this: a smartcard holds your private keys in […]

Roundup of remote encrypted deduplicated backups in Linux

June 11th, 2015, 17 Comments

Since I wrote last about Linux backup tools, back in a 2008 article about BackupPC and similar toools and a 2011 article about dedpulicating filesystems, I’ve revisited my personal backup strategy a bit. I still use ZFS, with my tool “simplesnap” that I wrote about in 2014 to perform local backups to USB drives, which […]

First impressions and review of OwnCloud

May 8th, 2015, 8 Comments

In my recent post (I give up on Google), a lot of people suggested using OwnCloud as a replacement for several Google services. I’ve been playing around with it for a few days, and it is something of a mix of awesome and disappointing, in my opinion. Files OwnCloud started as a file-sync tool, somewhat […]

Reactions to “Has modern Linux lost its way?” and the value of simplicity

February 11th, 2015, 77 Comments

Apparently I touched a nerve with my recent post about the growing complexity of issues. There were quite a few good comments, which I’ll mention here. It’s provided me some clarity on the problem, in fact. I’ll try to distill a few more thoughts here. The value of simplicity and predictability The best software, whether […]

Backing up every few minutes with simplesnap

February 13th, 2014, 10 Comments

I’ve written a lot lately about ZFS, and one of its very nice features is the ability to make snapshots that are lightweight, space-efficient, and don’t hurt performance (unlike, say, LVM snapshots). ZFS also has “zfs send” and “zfs receive” commands that can send the content of the snapshot, or a delta between two snapshots, […]

Migrated from Hetzner to OVH hosting

February 7th, 2014, 5 Comments

Since August 2011, my sites such as have been running on a Xen-backed virtual private server (VPS) at Hetzner Online, based in Germany. I had what they called their VQ19 package, which included 2GB RAM, 80GB HDD, 100Mb NIC and 4TB transfer. Unlike many other VPS hosts, I never had performance problems. However, I […]

VirtFS isn’t quite ready

February 7th, 2014, 9 Comments

Despite claims to the contrary [PDF], VirtFS — the 9P-based virtio KVM/QEMU layer designed to pass through a host’s filesystem to the guest — is quite slow. I have yet to get it to perform at even 1/10 the speed of the virtual block device (VBD). That’s unfortunate, because in theory it should be significantly […]

How to fix “fstrim: Operation not supported” under KVM?

February 6th, 2014, 9 Comments

Maybe someone out there will have some ideas. I have a KVM host running wheezy, with wheezy-backports versions of libvirt and qemu. I have defined a guest, properly set discard=unmap in the domain XML file for it, verified that’s being passed to the guest, but TRIM/DISCARD is just not working. Mounting the ext4 filesystem with […]

Why and how to run ZFS on Linux

January 23rd, 2014, 15 Comments

I’m writing a bit about ZFS these days, and I thought I’d write a bit about why I am using it, why it might or might not be interesting for you, and what you might do about it. ZFS Features and Background ZFS is not just a filesystem in the traditional sense, though you can […]

Debian-Live Rescue image with ZFS On Linux; Ditched btrfs

January 22nd, 2014, 10 Comments

I’m a geek. I enjoy playing with different filesystems, version control systems, and, well, for that matter, radios. I have lately started to worry about the risks of silent data corruption, and as such, looked to switch my personal systems to either ZFS or btrfs, both of which offer built-in checksumming of all data and […]

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