The Spokane Linux User’s Group has been meeting for over 10 years, discussing technology, Linux troubles, and advice. All are welcome to join us for festive Linux discussion over food and beer at Shari’s Restaurant, from the grizzled Unix long-beard to the timid newbie. There are no dues or registration – just drop by!
Meetings are held the third Wednesday of each month, at 7:00 PM. They generally run 1½ to 2 hours long.
Find us at Shari’s Restaurant, in the Spokane Valley, on N. Sullivan just south of Valleyway. 320 N Sullivan Rd. Spokane Valley, WA 99037 MAP
Richard presented some Bash scripting examples he uses for Vagrant-managed virtual machines; for setting up SSH sessions, monitoring the connections, and shutting down all connections when any one port breaks.
Thought of the day from Larry Wall: “The three chief virtues of a programmer are: Laziness, Impatience and Hubris.”
The most complete, authoritative technical guide to the FreeBSD kernel’s internal structure has now been extensively updated to cover all major improvements between Versions 5 and 11. Approximately one-third of this edition’s content is completely new, and another one-third has been extensively rewritten.
Three long-time FreeBSD project leaders begin with a concise overview of the FreeBSD kernel’s current design and implementation. Next, they cover the FreeBSD kernel from the system-call level down–from the interface to the kernel to the hardware. Explaining key design decisions, they detail the concepts, data structures, and algorithms used in implementing each significant system facility, including process management, security, virtual memory, the I/O system, filesystems, socket IPC, and networking.
Converting a PNG graphic file to PDF
One way is to install the ‘imagemagick’ package on your system (sudo apt-get install imagemagick), then use this at the command line:
convert sample.png sample.pdf
Multiple PDF files can be combined into a single, multi-page PDF with several different programs — my favorite GUI PDF page-manipulation program is ‘PDF Mod’, which allows you to add, delete, re-arrange, and rotate pages in PDF documents.
Members are testing out:
the ‘Plex’ media server — “it’s like having your own personal Netflix”; Debian Stable w/ Gnome 3 desktop; Clam AV for scanning for viruses on a server that hosts files for Windows computers; Linux Fest Northwest in May at SFCC; Chrome OS nice alternative for simple computing needs in virus-free environment; and CrashPlan for online back-ups.
Backing up your data 3-2-1 rule: always keep THREE copies of your data, on at least TWO different types of media, and at ONE different physical location.
Joe did a short presentation about effective Google searches: type in exact error codes; read every link on the first page because many entries below refer to and correct entries above, for stronger focus use the term twice in the same search, use ‘site:’ to search on a specific web site, use the minus sign to exclude a term or site from your search, include terms relevent to search but not general terms — known as “TFIDF”: Term Frequency Inverse Document Frenquency, quotes can pair seperate words into a single term, capital ‘OR’ will include both topics in a search.
“There’s an incredible amount of depth and thinking in the practices described here, and it’s impressive to see it all in one place.”
–Win Treese, coauthor of Designing Systems for Internet Commerce
The Practice of Cloud System Administration, Volume 2, focuses on “distributed” or “cloud” computing and brings a DevOps/SRE sensibility to the practice of system administration. Unsatisfied with books that cover either design or operations in isolation, the authors created this authoritative reference centered on a comprehensive approach.
Brad from the technology department at SFCC discussed their upcoming Linux Fest to be held Saturday May 9th. They are looking for presenters and exhibitors. More details will follow on the mailing list. Ben talked about Odoo, the new version 8 of the open source ERP system previously known as OpenERP and TinyERP. https://www.odoo.com/
Running the Mint distro, Samba servers, and rooting the Galaxy S3 phone. Nova program “Rise of the Hackers”. Using HTTPS can keep away “man in the middle” attacks assuming the CA authorities are not compromised. The “outer-net” — free internet from satellites? May start in 2015. Connecting to weather stations for public utility districts — driver code written with Linux.
Richard gave a short presentation on “incron”: trigger action when a file changes. There are some situations, when you need to start an action or run a command when a given file has changed in your file system.
incron :: inotify cron system. This program is an “inotify cron” system. It consists of a daemon and a table manipulator. You can use it a similar way as the regular cron. The difference is that the inotify cron handles filesystem events rather than time periods.
Discussion of synchronizing files with Unison and Rsync.
Richard talked about Vagrant: free and open-source software for creating and configuring virtual development environments. It can be seen as a wrapper around virtualization software such as VirtualBox, and around configuration management software such as Chef, Salt or Puppet.
Discussions: Developing a new secure web application for credit card transactions that ensures end-to-end security; Orcas Island; Orange County; Storms + servers and protection with UPS systems; Rathdrum Days this weekend; Palm OS; OwnCloud; Bittorrent Sync; Bitcoin block-chain technology being used for other applications such as messaging systems; wireless trackball / keyboards; the Supreme Court’s 9 to 0 opinion invalidating a software patent claim by Alice Corp; Richard Stallman and the GNU project and his January 2013 speech at University of Michigan: http://audio-video.gnu.org/video/2013-01-17_Stallman.ogv
Issues: a computer not getting to post when you turn it on — requiring another power-down cycle; getting contact lists into your phone; browser speed and loading pictures / content.
Gripes: Ribbon interface.
The small projector Ben is bringing to the meetings lately for presentations:
Dell M115HD WXGA 1280×800 HDMI USB Inputs w/ 1GB Internal Memory 450 ANSI Lumens Mobile LED Projector