Archive for the ‘Articles’ Category

Build a mini open source cloud to monitor/manage a larger vmware based cloud

Tuesday, December 25th, 2018

Calgary Linux Users Group Meeting

  • Date: February 6, 2019 — 5:45 to 7:30 PM
  • Place: Central Library 4-20F Meeting Room. (seating for 8)
  • Address: 800 3 Street SE, Calgary, AB T2G 2E7

I have been thinking of doing a presentation on some work I’ve done:

Using SaltStack to build personal private clouds on bare metal. Through the presentation I can sprinkle snippets of code from:

Raymond Burkholder
  • debian pxe boot files
  • how I use Saltstack to custom build pxe boot files
  • using iproute2 for kernel based network configurations
  • using Open vSwitch for layer 2 switching
  • using Free Range Routing for layer 3 route distribution with BGP, EVPN, anycast
  • using LXC for containers (rather than docker)
  • maybe some nftables configurations for basic security
  • how redundancy and resiliency is built into the solution

This configuration was used to build a mini open source cloud to monitor/manage a larger vmware based cloud.

My background can be found at https://blog.raymond.burkholder.net/

Dec 12, 2018 — Nose Hill Library Meeting

Wednesday, December 12th, 2018

Extra Meeting — Calgary Linux Users Group

Date: Dec 12, 2018 (Wednesday)

Place: Nose Hill Library – 1530 Northmount Drive NW, T2L 0G6, (Brentwood)
In Main Meeting Room

Time: 6:00 – 8:30 PM

Innovating your own solutions in GNU Linux.

Moved the backup data for Mint time shift.

I asked what the Dec 12 meeting was going to be about? The response:

Yes, I have the latest LTS Linux Mint but is anyone able to show us something else interesting or even better? I happen to have been looking into a Ubuntu flavor a customer of mine specifically requested.

Rather than do another Linux Distribution demo I took the opportunity to fix or repair a multi-boot laptop of mine that was developing some issues.

My chosen solution may also demonstrate some of the concepts well.
Oh, also I am ecstatic at having a working interim solution towards my goals.

Innovating your own solutions in GNU Linux.

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Calgary Linux Users Meeting Aug 8, 2018

Wednesday, August 8th, 2018

Date: August 8, 2018, (Wednesday)
Time: 6:00 – 8:00 PM

Place: Nose Hill Library – 1530 Northmount Drive NW, T2L 0G6, (Brentwood)
In Main Meeting Room

Topics: What we’ve been goofing around with in Linux (or also wanting to play with?).

Discussion of AGM Sept 5, 2018 plans (booked at Louise Riley Library)

Meeting is informal (yet fun). Looking forward to meeting with those who are able to attend at The Nose Hill Library.

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Annual General Meeting (AGM) June 20, 2018

Monday, May 21st, 2018

Important Annual General Meeting  scheduled!

June 13… It is only one week away from the AGM and there were minimal comments about elections so far.

Those new new to and revisiting GNU/Linux seem the fastest growing part of our group.

I would like to see information for computer fundamentals, followed by things specific to GNU/Linux. What ever I contribute will likely be GPLv3 licensed and epub or other open formats to share freely. The very nature of collaborative Linux is inclusive by nature so all are welcome.

We have seating for 40 people and we hope to end up with much more than a quorum.

Please note:

Additions to the club bank account signatory should happen as soon as the bank completes their paper work from our May 31 Letter of direction.

In an effort to be thorough in research I find I have to back off somewhat for now. Other technical volunteers stepping forward will be greatly appreciated. Otherwise things may take longer….

Interested in GNU/Linux?

Do you only see the possibilities and not the limitations?

Now is a good time to get involved.

Date: June 20, 2018

Time: 6:00 – 8:30 PM

Place: Nose Hill Library – 1530 Northmount Drive NW, T2L 0G6, Brentwood

In Main Meeting Room that Seats up to 40 people.

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Monthly Meeting — June 7, 2017

Thursday, May 25th, 2017

What is in it for you?

There are more topics for this meeting than just the demonstration/talk I promised.

  • TBA – a highly rated program I looked into (got 4.5 – 4.9 out of 5.0) that would seem to fit my clients needs and maybe our desires too. Up to date and runs on many operating systems. I will be asking your opinions at the meeting first rather than on line.
  • Learn more about membership benefits
  • More control over how you use your computer
  • Trust, Privacy and ease of use are being brought up or help requested. It use to be somewhat manual to set up but I have only started to look into this for more polished and modern applications.
  • Anyone still interested in help with installation or planning lets talk. The main kind of install, would require the least risk is a one blank hard drive install. (backups done or not needed) We can not call it anything like an install fest yet.
  • Some possibilities: Linux Mint (4 flavors), Linux flavored Solydxk rolling Debian LTS based on Stable, Debian Stretch for those up to it. My virtualbox got to kernel v 4.9.0 with aptitude safe-upgrade without seeming to break Stretch.
  • And three versions of Solus Linux including Gnome,plus KDE will be arriving soon.
  • Others?

 How easy has the Linux workstation/laptop become for personal and networking use?

Last month, if you remember, I showed something NOT to do for those that noticed the kernel panic from booting an incompatible Multi-boot Live-usb.

Until you try it out in real life I do not see how to answer this. So I plan to bring along a small example of my improved experience to the meeting to show. Your mileage may very.

  • With so many hardware installs to play with I found ways to break and fix booting up. Legacy mbr boots and GPT uEFI
  • To get there (OS and setup) I found I had to chose my path very carefully to save on time.

On top of this I will try out an advanced game demo that used to be overly complicated to set up.

My demonstration is using lesser hardware in the way of an older laptop with only 4GB RAM but it is lighter to carry and does the job ok ish :)

  • Flightgear has been around for quit a while and is becoming more capable and polished. But in the past it was a bear to setup at all. A demonstration will have to be a small subset of the possibilities in the interest of time. But even difficult tasks are far easier to accomplish now. My demo is based on one of the two modern distributions that seem capable
  • The point is to show how much it has improved along with Linux but I will not say is any easier to learn how to fly. For that you will want to get qualified instruction unless all you are concerned with is where do I reset the simulator?.

Public are welcome!

Time: 17:00 – 19:30

The Library closes at 20:00 (8:00 PM)

Place: Central Library

  • Meeting Place: Central Library, Basement Rm 2
  • Street address: 616 Macleod Trail S.E.
  • Calgary AB T2G 2M2   (refer to map below)

Seating:

  • 26 max at tables, more single chairs can be set up if required

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Monthly General Meeting — April 5, 2017

Thursday, March 30th, 2017

Meeting Time: 17:30 to 19:30

Is it easy to see the Club the way we want it?

Personally, I have been reevaluating many things including technology, Linux, Nature Walks, getting grounded and Keeping It Simple. More on this, I find not taking some risk more risky relating to my tech life. (avoiding the big ruts in my roads)

I will do what I will do. The Club… we will see.

Also, what is untenable?

Mailing lists have been too quite, but the meeting is still on (the room was booked towards the beginning of the month).

  • added Tuesday Apr 4 — btrfs-progs v 4.8.5
  • I am about to do some more tinkering with Butter FS in the next month or two. Would be fun to do a live demo of btrfs raid array if people find this of interest.
  • Starting off with the mystery btrfs raid1 three (usb) drives.
  • And a way to add one drive  and convert to raid10 if it strikes our fancy.
  • All with while live and mounted raid.
  • raid5/6 btrfs still not ready for production according to btrfs-progs coders.
  • Ways to get modern kernel versions
  • Possible drive failure modes?

No one has volunteered for a talk yet. The club reboot seems still in progress, so I will be patient.

More updates to follow in the next few days before the meeting.

  • Meeting Place: Central Library, Basement Rm 2
  • Street address: 616 Macleod Trail S.E.
  • Calgary AB T2G 2M2   (refer to map below)

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Examining a Next Generation Linux File System

Saturday, January 3rd, 2015

Feb 3

Revising this blog is in order, but not to hide my mistakes I think. Rather to show them or what else I may have learned. So if you are still interested, stay tuned. (and look below under Solydx on an eeebox for the red text) I knew it was wrong but had to try it anyway.

  • Also SolydXK’s updates now give you btrfs3.17 over v3.16

Jan 31

Unsure if I will be needing to give a talk on this at the Feb 4th meeting, as there seems little interest.

  • With out a system capable of running Virtual Machine I do not see any interesting show and tell. I do not have a capable lap top, for this, and my workstation is hardly portable.
  • Also some of my clients are needing help and they take precedence.

Jan 30

Tried btrfs-convert on an old Virtualbox machine

  • after conversion, the grub boot did not fully work and had to figure out how to update grub instead of just grub-install (using live boot)

Updates Jan 29


 

Publish early and publish often, the saying goes. But I hold back with “When I have something to say, I will say it”

1024 x 1024 x 1024 is the number of bytes in a GiB? (1073741824 Bytes) Did I get that right?
Had to refine how I was partitioning a drive for manual installs so I would not create a bit of a mess.
I would suggest hooking only one drive to your test system, 
to minimize risk of damage to existing installs. Just a thought.

Poking around with using btrfs more is driving me towards the quest of the ultimate user experiences. I would call this: Towards the Parametrically Driven Ultimate GNU/Linux Install. I have tried out a lot of different Linux distributions lately. The whole experience has left me both exhilarated and humbled.

  • Some progress instead of purely more questions
  • Leaving room for a bios_grub partition might be very important to keeping your btrfs GNU/Linux system grub boot-able?
  • Doing these non standard installs tends to prove out how much I do or don’t know, or if I was just lucky sometimes. Think I should try another install to see how repeatable I find things
  • My workstation is still running on ext4 for / and /home with added raid1 and raid10 btrfs arrays, all of which are running lzo compression. May wait longer to convert to / btrfs on my main system!
  • I have two physical systems running on “btrfs only” that I am happy enough with now
  • Trisquel on a netbook
 This is a refreshing distro, 
I really like how their Linux-libre Kernel 3.13 with lowlatency 
and bfq scheduling feels with btrfs root installed.
root@mel-1005PE:/home/mel# findmnt /
TARGET SOURCE FSTYPE OPTIONS
/ /dev/sda1[/@] btrfs rw,relatime,space_cache
root@mel-1005PE:/home/mel# findmnt /home/
TARGET SOURCE FSTYPE OPTIONS
/home /dev/sda1[/@home] btrfs rw,relatime,space_cache
root@mel-1005PE:/home/mel# mount
/dev/sda1 on / type btrfs (rw,subvol=@)
proc on /proc type proc (rw,noexec,nosuid,nodev)
sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
none on /sys/fs/cgroup type tmpfs (rw)
none on /sys/fs/fuse/connections type fusectl (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /sys/kernel/security type securityfs (rw)
udev on /dev type devtmpfs (rw,mode=0755)
devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)
tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755)
none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880)
none on /run/shm type tmpfs (rw,nosuid,nodev)
none on /run/user type tmpfs (rw,noexec,nosuid,nodev,size=104857600,mode=0755)
none on /sys/fs/pstore type pstore (rw)
/dev/sda1 on /home type btrfs (rw,subvol=@home)
systemd on /sys/fs/cgroup/systemd type cgroup (rw,noexec,nosuid,nodev,none,name=systemd)
gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,user=mel

Be very nice when their Kernel is next updated to more modern. Of all the installers, I think this one played nicest with an btrfs install I asked for.

 

  • Solydx on an eeebox
    • This one is installed on the single HDD (320 GB)
    • It is configured with 155GB partitions 1 and 2 with a 10GB swap partition  * (This is a bad idea, the self healing gained is NOT worth the pain of worse than poor hard drive performance – I no longer have this configuration)
    • So instead of the mirror listed below, / btrfs will be set up under one partition and backup down to an external drive. If this device could take more than one drive, raid1 mirroring could be an interesting option to try, but its limited to only one drive.
    • This gave me a btrfs raid1 mirror operating system File System that is boot-able from both /dev/sda[1 and 2] just using the grub menu
    eeebox mel # gdisk /dev/sda
    GPT fdisk (gdisk) version 0.8.10
    Partition table scan:
     MBR: protective
     BSD: not present
     APM: not present
     GPT: present
    Found valid GPT with protective MBR; using GPT.
    Command (? for help): p
    Disk /dev/sda: 625142448 sectors, 298.1 GiB
    Logical sector size: 512 bytes
    Disk identifier (GUID): 86B538AB-BE5D-4CB8-B0F0-273EC36EBF1D
    Partition table holds up to 128 entries
    First usable sector is 34, last usable sector is 625142414
    Partitions will be aligned on 2048-sector boundaries
    Total free space is 2669 sectors (1.3 MiB)
    Number Start (sector) End (sector) Size Code Name
     1 2048 302735359 144.4 GiB EF02 primary
     2 302735360 605468671 144.4 GiB EF02 primary
     3 605468672 625141759 9.4 GiB 8200
    l list known partition types
    ef00 EFI System ef01 MBR partition scheme ef02 BIOS boot partition
    eeebox mel # parted /dev/sda
    GNU Parted 3.2
    Using /dev/sda
    Welcome to GNU Parted! Type 'help' to view a list of commands.
    (parted) p
    Model: ATA ST9320423AS (scsi)
    Disk /dev/sda: 320GB
    Sector size (logical/physical): 512B/512B
    Partition Table: gpt
    Disk Flags: pmbr_boot
    Number Start End Size File system Name Flags
     1 1049kB 155GB 155GB btrfs primary bios_grub
     2 155GB 310GB 155GB btrfs primary bios_grub
     3 310GB 320GB 10.1GB linux-swap(v1)
    eeebox mel # df -h
    Filesystem Size Used Avail Use% Mounted on
    /dev/sda1 289G 13G 275G 5% /
    udev 10M 0 10M 0% /dev
    tmpfs 1.5G 18M 1.5G 2% /run
    tmpfs 3.8G 76K 3.8G 1% /dev/shm
    tmpfs 3.8G 0 3.8G 0% /sys/fs/cgroup
    tmpfs 100M 12K 100M 1% /run/user
    tmpfs 5.0M 4.0K 5.0M 1% /run/lock
    eeebox mel # btrfs fi df /
    Data, RAID1: total=7.00GiB, used=6.04GiB
    Data, single: total=8.00MiB, used=0.00
    System, RAID1: total=8.00MiB, used=16.00KiB
    System, single: total=4.00MiB, used=0.00
    Metadata, RAID1: total=1.00GiB, used=226.25MiB
    Metadata, single: total=8.00MiB, used=0.00
    unknown, single: total=80.00MiB, used=0.00
  • Also a virtual box version of openSUSE with not only / btrfs, but also /home btrfs instead of the default xfs that SUSE pics.
  • Since this seemed much like uncharted territory, I did many trials to see if I had things some what figured out. Found more questions as I looked, but did make a lot of headway. I could bring stuff to the meeting Feb 4th, but IS there any interest?
  • One thing I thought might be fun is to install btrfs system to a usb drive
  • What was interesting was the odd ball troubles I ran into forced me to see the basics more clearly. I will continue to play with btrfs and learn more
  • Is kernel version 3.19 still due to come out the beginning of February? I wanted to see if I can plan a live morph of my raid1 and raid10 into a raid5 hard drive array (6 disks) Then maybe into a raid6 to try that too.

Who May Be Interested in Attending?

Desktop 1_003

btrfs Only (No EXT)

At first I thought; Anyone who is interested in some way with modern computers.

Btrfs is or could be used in everything from small devices to servers and lots in between. It could also make it easier to breath some new life into older equipment for the hobbyist.

My Data and OS Backup Plan Is In Place…. Is Yours?

I took other peoples advice and had backups before trying things out. Also, I used new virtual machine for installs I was willing to loose.

My Motivations

  • I wanted to try out… as in get my hands on as many cool new features of the B-Tree File System that I could
  • Next, to share my endeavors before the next new Linux Kernel comes out and see if any one else has been delving it to it
  • Finally, to share anything I find that others may find interesting or useful
  • I did discover learning and using btrfs to be some work (*) but a huge amount of fun too!  (because it works so differently)
  • The new Linux kernel coming out late January may fix btrfs, but what will the Linux distributions do with making front ends fore using it!

B-Tree File System (btrfs)

Newer Linux Kenels are advancing, and I could not wait. B-Tree FS, butterfs, better fs, or just btrfs.
Nicknames aside,

It is turning out to be a lot of fun learning the new ways of thinking about file systems. The benefits list has to be seen in real life to be more fully appreciated.
Come and share your experiences with us too. I have been using btrfs_3.16 lately. More on version 3.19 later
Thanks Anand, for getting me started a few months back with your intro demo, btrfs appears less unstable than claimed (with a modern enough kernel).

  • As I figure things out I will update you on what I think I know & don’t know.
  • Next demo, if there is one. will include or mostly be seeing it in action

Looking at ZFS in Comparison

ZFS or FreeBSD is great way to protect your data with redundant data pools. New groups of redundant arrays can be added, changing the structure of existing arrays would involve backing up and moving the data after re-silvering the data arrays.

At risk of being blunt with btrfs  things are done mostly on live system. Looking forward to what seems to be possible.

 

Some of My Goals

  • Running btrfs on the operating systems root file system. [ My first success waslon ext2 /boot and btrfs / ][most likely the trick will be to get the installer to accept btrfs as an accepted file format
  • Use btrfs send/receive for high speed block differential backups
  • Have Rollbacks Available [ some work to do… openSUSE 13.2 has it already, see snapper  ]
  • Fast and Easy Device Setups and On The Fly Changes [ built in ]
  • Make Summary of Useful Commands and Examples [coming]
  • btrfs3.16: raid0, raid1, raid10  btrfs3.19 coming with major improvements to raid5 and 6
  • Running btrfs raid5and6 arrays [on btrfs 3.17 DONE on VirtualBox – 6 10GB drives] [On btrfs 3.19 next on spinning  drives]
  • How to think about free space
  • Update blog more

Who and How Are Companies and People using btrfs?

  • Facebook
  • Fujitsu
  • Fusion-IO
  • Intel
  • Linux Foundation
  • Netgear
  • Oracle is using it in a production product
  • Red Hat
  • Stato
  • SUSE / Novell openSUSE 13.2 uses / btrfs on defaullt install of workstation

How all of these companies use btrfs in their products is noteworthy

 

How I Approached Looking at This Moving Target

The man pages for btrfs_3.16 indicated some of the syntax changes, and looking at what others have been doing [references to follow]

[this blog is presently dynamic and not completed]

I am working on this after the January 7th Meeting too. I can share more with anyone who may be interested.

Some results?

Got btrfs install on root first on Solydxk by tricking the installer and Grub2 to cooperate

Conclusion:

Presentation Not far enough along for show and tell January 7th. The raw video capture proof was not able to grab peoples interest. This idea has to have an Operating System people can see running in real time. [Will be adding test snippets to make following along easier.]

btrfs is more a verb than a noun.

Meeting — Dec 3, 2014

Tuesday, December 2nd, 2014

The next meeting is scheduled for December 3, 2014 at the U of C Downtown Campus, room 318, at 7 p.m. As always, the meeting is open to members and non-members. We’ll take a look at XBMC, a media server and client. Learn to organize your media, add metadata automatically and stream it to another device.

After the meeting we usually head over to Brewster’s/Beer Revolution, which is within walking distance of meeting location. Even if you can’t make it to the meeting, you’re welcome to join us for beers.

Anand.

Room 426
U of C Downtown Campus – 906 – 8th Ave SW
data=VLHX1wd2Cgu8wR6jwyh-km8JBWAkEzU4,CZCRDL1UHe_jc1Ne18oxymvU0KONWMeUkzJE0goTprIqt2-cJ2Kz4yKTT2LlDULg8AQbMgwU6HPXx32LG6U4uhqaZ2eQRWQxAU3YVHNwK7oOF14x-w
Parking in the Campus building is $3. Free street parking nearby is available.

Far Out

Friday, May 9th, 2014

Linux Foundation Training Prepares the International Space Station for Linux Migration

It’s hard to get tech support 400 kilometers away from the Earth,…
a NASA contractor deeply involved in Space Shuttle and International Space Station (ISS) operations, decided to migrate to Linux.
URL: (Read the article.) Check out their FREE courses too!
http://training.linuxfoundation.org/why-our-linux-training/training-reviews/linux-foundation-training-prepares-the-international-space-station-for-linux-migration 

Using the program Celestia to display a simulation of the International Space Station

Far out

Far out!… Linux goes into outer space

 

Future of Linux User Groups

Thursday, March 13th, 2014

Mel Walters

Insanity Keep repeating the same again and again and expecting different results.
(definition by Albert Einstein)

Being Remarkable

Peoples’ expectations have changed. The new normal is remarkable, [1]  or something worthy of remark. Call it weird, normal is just plain boring. Authenticity[2]  is also a must.
I propose we stop being boring or irrelevant; and remarkable will become easier with practice.

What Can We Do?

Here are a few ideas:
  • Improve things for people who want to be creative and not fussing with their computer all the time. Minimize incomplete, inaccurate or bad technical advice. I will use virtual machines to try out my own advice. There are definite advantages in doingsomething including:
    • Installation dependency requirements will all be met by starting with a base system install.
    • Achieving letter perfect documentation by copying from true to life examples, even though they be virtual.
    • Not having to disturb your real system to do the trial runs.
    • Define preferred Linux distributions and configured programs to fulfill desired functions.
    • Being able to prepackage a custom Linux distribution may also work out as a bonus. I will be trying this on my virtual-box.
    • Instructions can be considered adequate only if clear and complete enough to be followed to success.
  • Do something. A perceived risk will not be as risky as doing nothing at all.
  • Look at the whole job. Being only 98 percent done is is very frustrating. Don’t stop short.
  • Do not become hypnotized into self imposed limits.
  • Let us drop the black and white, right and wrong. Adopt Integrative Thinking.[3]  So by seeing both sides, you pick neither one or the other, but come up with a better solution. (You keep more friends this way too.)
  • Everybody is really good at something, so look inside and drop the “I can’t”.
  • We repel those we really need; if we put false class distinctions on abilities.
  • It takes demonstration (leading), not memos or bylaws to change culture. [4] 
  • Questing for the ultimate programs/operating system combination is worth revisiting. Thanks Jerry for pointing out Solyd XK Linux, looks interesting. I have taken it for a spin in virtual-box.
  • Just to show you we can be interesting, I would like to give a talk about how cool and easy high quality FOSS[5]  self publishing is these days. Now why on earth would that be useful or noteworthy in our modern economy? (e-publishing and paper too)
  • By appreciating our potential and present members,[6]  boring will go out the window.
  • Freedoms and Fair Use “License”: Abundance is the new market, not scarcity. It’s like Love; It works when you give it away. Don’t hold back. Trust your customers and they will trust you. When they trust you they will buy from you. Think of it as the only thing that scales big and small. There is no where to hide in our information economy. Share your knowledge.
  • There are 10(2) types of people in the world; Spoiler [7] 
    • 1(2) Those who get it.
    • 10(2) Those who don’t.
  • You can join a local LUG,[8]  or if that will not work for you, consider joining ours.
At our last meeting I saw a passion in some to experiment, to try out new. They may be among our future leaders? All it takes is joining our mailing list,[9]  and your involvement qualifies you as a Tier I member of CLUG[10] .
People are telling me that meeting in person is still important. Lets face it, we must have fun while doing it.
The future looks bright for CLUG, to anyone willing to collaborate in doing what’s needed. Complicated has to get easier and easier, do more with less!

Notes

1)  Seth Godin, Book: Purple Cow – Transform Your Business by Being Remarkable (2009)
2)  Seth Godin, Book: All Marketers Are Liars Tell Stories: How Marketing Really Works
And Why Authenticity Is the Best Marketing of All (2012)
3)  Roger L. Martin, Book: The Opposable Mind – Winning Through Integrative Thinking (2014)
4)  Jason Fried; David Heinemeier Hansson, Book: Rework (2010) from 37signals.com and basecamp.com
5)  Free(dom) and Open Source Software
6)  those wanting to use such cool technology as Freedom and Open Source Software
7)  10base2  = 2base10  think binary numbers
8)  Linux User Group
9)  Club members have experimented with things like IRC chat in the past, so keep in mind other ways to collaborate.
10) http://clug.ca/membershi/

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