Tag Archive for SSH

Custom PC, Issue 179

Custom PC Issue 179This month’s Hobby Tech column takes a look at an open-source microcontroller-driven hobbyist oscilloscope and a book which aims to document art in video games, while also walking readers through the rather handy trick of setting up a reverse SSH tunnel.

First, the tutorial. Since Code42 announced that CrashPlan Home, my chosen off-site backup solution, was being discontinued, I’ve been looking into alternatives. A Raspberry Pi with a USB hard drive and a copy of Syncthing installed does the job nicely, except for the issue of management: once it’s off-site, I’d have to configure someone else’s router to forward a port so I can SSH into it. An easier alternative: a reverse SSH tunnel.

Where a traditional SSH connection goes from local device to remote host, a reverse tunnel goes from remote device to an intermediary device – in my case, a home server on my own network. Your local device then also connects to said intermediary device, and you have full access to the remote device regardless of whether or not it’s behind one or more firewalls or even whether you know its public-facing IP address.

The first of the reviews, meanwhile, is a little cheeky: while the device on test is based on the JYE Tech DSO138 open-source oscilloscope design and firmware, I’ve been using a clone rather than an original – having spotted it on offer during an Amazon sale and been unable to resist a bargain. While the conclusions I draw on the scope’s functionality and usability apply equally to both, a first-party JYE Tech version is likely to feature better build quality and certainly includes better support.

Finally, my review of the coffee table tome – yes, another one – Push Start: The Art of Video Games is one of those rare occasions where I’ve been disappointed by what should have been a product aiming for a very low bar. While the full-colour hardback publication includes plenty of high-quality pictures, it also includes some extremely low-quality screenshots as well – particularly noticeable at the beginning where vector games are captured as bitmaps using MAME’s default ultra-low resolution, and at the end where tell-tale artefacts show the use of third-party JPEG images rather than first-party captures. Worse still is the limited accompanying text, which is riddled with errors.

The latest Hobby Tech is available now from newsagents, supermarkets, and electronically via Zinio and similar digital distribution services.

Linux User & Developer, Issue 141

Linux User & Developer Issue 141In the latest issue of Imagine Publishing’s Linux User & Developer, in addition to my usual four-page spread of the latest news from the world of open source, I review the Synology DS414j network attached storage (NAS) system and the Duo Security two-factor authentication platform.

I actually came across Duo Security when I learned that support for the platform had been added to the LastPass password management service. Signing up for an account and registering my details, I found that the software could be quickly and easily used to protect an SSH server – and with more than one public-facing SSH server, that piqued my interest.

Duo Security is a two-factor authentication system which uses push messaging to a smartphone application, turning your phone into the ‘thing-you-have’ portion of the setup and precluding the need to buy a dedicated security token. There’s fallback to other authentication measures, from offline token generation similar to Google Authenticator through to SMS and even voice call functionality. Better still, an account is free for ‘enterprises’ of fewer than ten users.

The Synology DS414j, meanwhile, is the latest NAS device to appear from the company and one designed as an upgrade from its popular dual-bay boxes. Featuring four 3.5″ SATA drive bays, the DS414j comes with Synology’s excellent DiskStation Manager (DSM) Linux distribution, but there’s little doubting corners have been cut: the drive bays are not hot-swappable for a start, which means downtime if you need to swap out a failed drive.

My conclusions on both products, plus my take on the most interesting open-source stories of the month, can be yours with a simple trip to your local newsagent or supermarket, or digitally via digital distribution services like Zinio.