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MUUG Monthly Meetings for 2018-19

Please note our current meeting location: 1M28 Manitoba Hall, University of Winnipeg, entrance on Ellice Ave. between Spence and Balmoral St. (Check out the UofW's maps for nearby parking locations.)

Meetings start at 7:30pm sharp.

September 11, 2018: Managing Systems with Ansible

Ansible is an OSS IT automation engine, in the vein of Chef and Puppet. But what exactly can you do with it? John Gunkel filled us in. He covered key concepts, package management, templates, roles, GUI interfaces, and more!

RTFM: tcpdump(1) with Adam Thompson

Debugging an application's behaviour is sometimes easier to do by looking at the interactions it has with other systems on the network than by examining the application itself. Modern UNIXes all come with a tool, tcpdump(1), that can examine, filter, decode, and log all the traffic seen at a network interface - whether it originates on that system or not. Adam discussed the most common options for tcpdump(1), and demonstrated a simple example.

October 9, 2018: Reproducible Builds

Many of us run some amount of Free and/or Open Source Software, but how can we ever be sure that what we're actually running was built from the allegedly published source code? Whilst not a complete security solution in and of itself, this project helps influence and improve security and development as part of a wider set of policies. Presented by Muz, this short talk introduced the issues with trying to obtain reproducible builds, and some of the work that has been done to date on certain code bases, particularly with the Debian distro.

RTFM: netcat

A look into a computer networking utility for reading from and writing to network connections using TCP/IP protocol, designed to be a reliable "back-end" tool that can be used directly or easily driven by other programs and scripts.

Note that there are two versions of netcat (or the nc command) that are widely available: the traditional "Hobbit" netcat(1), and the ncat(1) command that comes as part of Nmap. This presentation by Wyatt Zacharias focused on the latter. (Adam Thompson focused on the former in a June 2014 RTFM.)

November 13, 2018: Build an IP Captive Portal from Scratch

(For Fun and Education, but Not for Profit)

Love 'em or hate 'em, captive portals are widely used to restrict Internet access to authorized users. What if you need to set one up, but all the "canned" solutions aren't quite right for your use case? This presentation by Gilbert Detillieux showed the various components that make up a captive portal, and how you can set one up from scratch, using Linux Netfilter/iptables, ISC DHCPD and BIND, the Apache web server, and some custom back-end scripting.

Gilbert has made his presentation slides, in PPTX and PDF format, available online.

RTFM: date

The lowly date(1) command has been a fixture of UNIX systems from the very early days. Yet there may be features in this command that would surprise you. Adam Thompson presented this RTFM, and compared features of the date command from various systems, including Solaris, OpenBSD, macOS, and GNU/Linux.

December 11, 2018: RTFM: time, Round-table, Mingling and Munchies

RTFM: time

A short demonstration of the Unix time(1) command by Wyatt Zacharias. Time is used to determine the duration of execution of a particular command. Wyatt's presentation covered both the built-in time command in bash(1), and the external (GNU) time command, including default and explicit output formatting in each. Wyatt also talked about the which(1) command, as well as the bash-built-in type command, that you can use to find out if a specified command is built-in or not. (There was also mention of quoting the command name, e.g. by preceding it with a "\", to bypass built-ins, and of using explicit pathnames to distinguish between multiple external commands with the same name.)

Round-table, Mingling and Munchies

As 2018 drew to a close, MUUG continued our recent tradition of turning the December meeting into more of a social event. Cookies and pop were provided by MUUG, but members were encouraged to bring their own finger food to sample and share.

Winnipeg Harvest Food Drive

Also as in previous years, we combined our pot luck with a food drive for Winnipeg Harvest. Cash donations were preferred this year as every $1 Winnipeg Harvest receives, they are able to pick up and deliver $20 worth of groceries. MUUG members were generous again in both their cash and food donations.

January 8, 2019: Test Driving oVirt with Nested KVM

oVirt is a KVM based virtualization solution by Red Hat which works on a data-centre / multi-server scale. Mark Jenkins showed that you don't need a rack full of servers or a SAN to try it out or simulate a production environment. The secret sauce for this is nested KVM.

February 12, 2019: Cacti

Cacti is an open-source, web-based network monitoring and graphing tool designed as a front-end application for the data logging tool RRDtool. Cacti allows a user to poll services at predetermined intervals and graph the resulting data. Wyatt Zacharias gave us a new look at this software with his demo.

RTFM: systemctl(1)

Most Linux distros have now adopted systemd as the new init process. Gilbert Detillieux introduced the very basics of using systemctl(1) to control services in a systemd-based environment, and showed a few useful options and features.

March 12, 2019: A Looking Glass Server with OpenBSD and OpenBGPD

Adam Thompson talked about setting up a BGP Looking Glass server quickly using OpenBSD and OpenBGPd, as well as how he used the UNIX "toolkit" to solve some BGP analysis and visualization problems. The presentation (which was quite a bit longer than the setup time) included many interesting tangents about OpenBSD support, installation, and configuration, VMware configuration for BSD variants, what good (vs bad or missing) man pages should look like, setting up SSL certificates using letsencrypt, the Manitoba ISP landscape, and much more.

Adam has made his presentation slides, in PPTX and PDF format, available online.

The round-table discussion at the start of the meeting covered many, varied topics, including dealing with frozen pipes (literally), and running a pipeline filter conditionally only if there's output (solution is to use the ifne(1) command, which is usually part of an optional "moreutils" package in several Linux distros).

April 9, 2019: WINE

Kevin McGregor covered the state of the WINE project, software which enables you to run Windows software unaltered on Linux-based systems, and of a commercially supported version of it called Crossover. Kevin's presentation included a demo of installing a Windows app, Notepad++, under WINE.

RTFM: xargs(1) Redux^2

Adam Thompson once again turned his attention to xargs(1), and demonstrated scripting techniques that allow parallel processing using nothing but standard UNIX tools, and the xargs -P option.

May 14, 2019: AWS VPC (Virtual Private Cloud)

Wyatt Zacharius showed us Amazon Virtual Private Cloud (Amazon VPC) which lets you provision a logically isolated section of the AWS Cloud where you can launch AWS resources in a virtual network that you define. You have complete control over your virtual networking environment, including selection of your own IP address range, creation of subnets, and configuration of route tables and network gateways.

RTFM: Stupid Bash Tricks

Members were amazed, delighted, and confused by Katherine Scrupa, as she showed odd things you can do in Bash.

June 11, 2019: PDF::Reuse - Reuse and Mass-produce PDF Documents

Brad Vokey demonstrated a Perl module, PDF::Reuse, that specializes in mass-producing efficient multi-page PDF documents by reusing an original PDF file as a template. This module was the perfect tool to help him create many multi-page PDF result forms for his Matchomatics business (with many over 1000 pages each) quickly and easily while at the same time keeping file sizes small and efficient.

RTFM: pstree(1) and a few other tricks

Gilbert Detillieux did an off-the-cuff presentation on the pstree(1) command, showing some potentially useful features of the command, and talking about different options in different implementations, available (either in the distro or as an add-on) on different platforms.

Adam Thompson talked about some tricks to keep two systems with Ansible playbooks in synch, in such a way that either can be the "master" and act as a backup for the other.

And finally, after his presentation, Brad Vokey demonstrated a web site, wttr.in, that displays the current weather for your location using only UTF-8 characters in the output, so it can be run from the command line, (e.g. curl wttr.in).

July 2019: No meeting this month

August 2019: No meeting this month

Please note our current meeting location: 1M28 Manitoba Hall, University of Winnipeg, entrance on Ellice Ave. between Spence and Balmoral St. (Check out the UofW's maps for nearby parking locations.)

Meetings start at 7:30pm sharp.

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