NSLIG – June 2017

Notes from the June 2017 Meeting

Nick Vespo was unable to be with us for the June Meeting due to a customer need, so the meeting started with the Open Forum session chaired by David Hatton. He started proceedings by advising that the default Raspberry Pi password should be changed as soon as possible after the first boot. There have been instances of user systems being hijacked because the default password is so well known and widely publicised.

The first question from the floor related to computing “appliances” and how often they should be re-booted. It is not always easy to find a window of opportunity for these appliances because a re-boot could interrupt a running process that is critical. There is no clear answer that fits all situations, but the suggestion was that a cron job timed to start at something like 3:00 a.m. could cause the least risk of disruption.

Then a question about Linux vulnerabilities was addressed. Desktop installs of Linux are not such a target for viruses and other malware as desktop Windows. There are anti-virus programs for Linux, but David has been running desktop Linux without them for more than a decade and has not (so far) had a virus infection. Ad Blocking software can be useful – ublock origin was recommended.

David ran Shields Up (from grc.com) to check if the Linux Mint system used for the meeting was vulnerable through ports that might be “invaded”. Shields Up checked the first 1024 ports, and all were assessed to be operating in the desirable ”stealth” mode.

A question from a new-ish user of Linux about Mint brought the response that it is a polished version of Ubuntu long term support versions. It can use any of the Ubuntu desktop environments, such as Unity, Cinnamon, Mate, Gnome or KDE, but it is not advisable to to continually run more than one desktop at a time – that can sometimes confuse the system and produce strange results.

The last question before the break was whether it is possible to run Linux on an older Mac system. There was no clear answer given, partly because no-one present had tried that combination. Opinions about the likelihood of success included a comment that there may be problems with getting the system booted, because of differing boot strategies.

After the social break, David Hatton presented one of his continuing series of Random Bytes sessions. Two topics were covered, the first being about a program called “glabels”. As the name suggests, its main purpose is to print labels. But it can also be used to create cards of various types, including – for example – birthday cards.

The program provides templates for many of the commonly-used label sheets and can generate labels for items to be sent to a list of recipients via email. It can do a similar job for cards created with the program. David demonstrated the card creation by building a birthday card with a message and picture on one half and the “Happy Birthday” greeting on the other half of the card.

The greeting had to be inverted in order for the card to show correctly when printed. The inversion was achieved by taking a screenshot of the text, loading the screenshot into an image viewer, flipping the text into the desired orientation, and moving the flipped version back onto the card. Simple – once you have seen it done. A little lateral thinking can pay off.

Then David showed us Turnkey Linux – a distribution aimed at creating Linux systems for computing appliances of various sorts. The web site is at … http://www.turnkeylinux.org

and claims that there are more than 100 pre-built types of system images for immediate use. The WordPress version was chosen, and installed in a virtual machine. That way, if something goes awry, the virtual machine installation can simply be removed without major consequences to the environment.

The guest VM was set up and the WordPress image installed without drama, and operated as expected. Turnkey images are quite small because they are custom-designed to do only a specific task. This might be a good entry point for the much-hyped Internet of Things.