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Total Running Time: 2:25:49
Un-edited Live session – http://www.youtube.com/watch?v=TjU-jfObR3o
Contact Us:
show (at) smlr.us or the Contact us page
Summary
Kernel News: Mat
Time: 16:45
Distro Talk: Tony
Time: 18:45
Penguicon 2015: Kevin Obrien
Time: 51:30
Mat’s Half Book Review
Time: 1:26:00
Tech News:
Time: 1:44:00
Convention Scene:
Time: 2:00:00
Listener Feedback
Time: 2:05:15
Outtro Music
Time: 2:14:30
Intro:
Tony Bemus, Mat Enders, and Mary Tomich
Sound bites by Mike Tanner
Kernel News: Mat
Time: 16:45
https://www.kernel.org/
mainline: 4.0-rc6 2015-03-29 stable: 3.19.3 2015-03-26 longterm: 3.18.10 2015-03-24 longterm: 3.14.37 2015-03-26 longterm: 3.12.39 2015-03-19 longterm: 3.10.73 2015-03-26 longterm: 3.4.106 2015-02-02 longterm: 3.2.68 2015-03-06 longterm: 2.6.32.65 2014-12-13 linux-next: next-20150402 2015-04-02
Distro Talk: Tony
Time: 18:45
- 3-23 – Distribution Release: SuperX 3.0
- 3-24 – antiX 14.4 “MX”
- 3-24 – Ubuntu MATE 14.04.2
- 3-24 – Black Lab Linux 6.5
- 3-25 – GParted Live 0.22.0-1
- 3-26 – NethServer 6.6
- 3-27 – Voyager Live 14.04.4 “X”
- 3-27 – Zentyal Server 4.1
- 3-30 – BlackArch Linux 2015.03.29
- 3-31 – Linux Lite 2.4
- 4-1 – CentOS 7.1-1503
- 4-3 – Emmabuntüs 3 1.01
Distro of the Week: Tony
- openSUSE – 1218
- Debian – 1476
- CentOS – 1677
- Ubuntu – 1784
- Mint – 3065
Penguicon 2015
Time: 51:30
2015.Penguicon.org
Kevin O’brien Comes on to talk about the Open Source and Science Fiction Convention in the Metro Detroit Michigan:
Penguicon 2015 Schedule
http://2015.penguicon.org/this-year-at-penguicon/#schedule
Tony:
– Friday at 4pm – Practical Home Networking Using a Linux Router
Mat:
– Friday at 4pm – Bash Scripting for Beginners
– Friday at 7pm – Bash Scripting 201
– Saturday 6pm – Using RegEx in grep
Mary:
– Sunday at 12 noon – Swimming with Dolphin, the File Manager
SMLR E150: Sunday at 8am
** All Times are in the Eastern Time Zone
Mat’s Half Book Review
Time: 1:26:00
Tarsnap Mastery:
Online Backups For The Truly Paranoid
Michael W. Lucas
Website: https://www.michaelwlucas.com/
Blog: http://blather.michaelwlucas.com/
Book: https://www.michaelwlucas.com/nonfiction/tarsnap
If use any *NIX type system and need off-site backups, then you need Tarsnap, and if you want to use Tarsnap efficiently you need “Tarsnap Mastery.”
While using the book to set up and start using Tarsnap, I only had to look at the manpage once and that was because I misread an instruction in the book. “Tarsnap Mastery” explains everything clearly and in detail.
That was the quick review now to the in depth look at “Tarsnap Mastery” by Michael W. Lucas.
First a note about the chapter numbers. They are in octal so no chapters 8 and 9 are not missing.
Chapter 00: The Backup Problem
The first thing Michael Lucas talks about is problem of back ups. He starts with a look at the historical tape archive system, that gave us the tar command that and was the inspiration for Tarsnap. Then this chapter goes on to explain the difference between compression and deduplication, and how Tarsnaps’ deduplication is way better than compression. Then we learn how Tarsnaps’ encryption takes place entirely in the client that runs locally. He also delivers the best quote I have ever heard on encryption “A mediocre encryption algorithm used well is more secure than a great algorithm used badly.” Then the book goes on to explain not only is it technically transparent by providing the source code but legal transparency. Since all encryption occurs client side if Tarsnap is subpoenaed they can’t give up much. All they know is when you connect and how large your uploads are. To quote the book again “The point of Tarsnap is that you have no need to trust anyone outside yourself with the contents of your data. Nobody can access your data without your keys—period.”
Chapter 01: Tarsnap Essentials
Now this chapter of “Tarsnap Mastery” explains the different components of Tarsnap along with it philosophy, like how they are completely transparent about outages and the only reason they have ever used more than once was “Amazon broke.” It then touches on the intended user base for Tarsnap being “Unix system administrators and developers. It’s clearly not designed for casual users of consumer operating systems.” Then the subjects of how to get support, its security the operating systems supported is covered, and of course the awesome deduplication is covered again. The only exception I have with this book is a footnote on page 20, the shebang /bin/bash is the one true shebang, but then my personal website is bashjunkie.org. Also in this section how you pay for the service is covered. It is a prepay model that is quite inexpensive, granted for my testing I used a small directory (40MB), I did a creation and a restore and it cost me a little less than 1/2 a penny.
Chapter 02: Installing Tarsnap
“Tarsnap Mastery” covers installing Tarsnap quite extensively and I am sure they work as advertised. It was not in the repos I enable on my servers:
repo id repo name
base/7/x86_64 CentOS-7 – Base
epel/x86_64 Extra Packages for Enterprise Linux 7 – x86_64
extras/7/x86_64 CentOS-7 – Extras
updates/7/x86_64 CentOS-7 – Updates
So being lazy I found a simple script online that installed Tarsnap for me. It’s a pretty simple script that is easy to read and understand what it is doing, which is important as it needs to be run as root. My rule of online scripts is if you can’t read it and understand what it is doing DON”T RUN IT. That being said here is a link to the script:
https://gist.github.com/dhensby/6371274
Chapter 03: Tarsnap Client Basics
In this chapter of “Tarsnap Mastery”, by Micheal W. Lucas, you will be walked through Key creation and registering a machine with Tarsnap. You will also be walked through your first backup and extraction. You will also be given some help with debugging. This is all accomplished in a friendly straight forward manner. Look I said that with a straight face. The configuration file is explained in good detail. The only fault I have with it is the sample file contains to little. In my opinion it should more information in the way of a comment line with a commented out configuration option.
Chapter 04: Creating and Managing Archives
One of the best lines in the book is in this chapter. It is about why Tarsnap does not have a progress meter, “Any Tarsnap progress meter would make those in commercial operating systems look sensible and trustworthy.” You will also be instructed how to completely manage your archives from creating to viewing and deleting. An excellent part of this chapter is how it explains some of the pitfalls you can encounter with the include and exclude functions. It tells you how you can shape the traffic limit the I/O. One of the great features is it honors the nodump flag setting on files. It also can save you from yourself. During my testing I wrote a simple backup script that appended the date to the file name. Now if I was running it twice in the same day (which during testing I did), I would delete the archives first but once I forgot and Tarsnap refused to run the backups because the archives existed. You will also learn about checkpoint, that is what Tarsnap uses when a back up is interrupted so it knows where to start from. Tarsnap does support regex however its implementation is a little shaky as Michael mentions in this footnote “Let’s say you have a problem, and you decide to solve it with Tarsnap’s regular expressions support. You now have three problems.”
Chapter 05: Caches and Keys
In this chapter Michael teaches us how to maintain our cache directory. Making subkeys and setting their permissions and passphrases. This will help prevent things like accidental deletion of backups. Then you’re told in very simple terms how to share a key on multiple servers, in short DO NOT DO THIS.
Chapter 06: Backup Rotation and Automation
First thing in this chapter of “Tarsnap Mastery”, Michael disusses deciding on a rotation scheme. Then there are three different backup automation options presented Feather, Tarsnapper, and ACTS. The first two Feather and Tarsnapper are written in Python, but the third ACTS is written in shell, so geuss which one I went for. Michael also chose ACTS so the rest of this chapter goes int the details with ACT, from installation and configuring it, through scheduling and rotating your backups. The only glitch was I could not find the tarball Michael mentions, but the thfiles were so small, the largest was only 6.2K, so I just used wget to get the five files one at a time. The script is a straight forward shell script, if understand shell you will have no problem reading it and understanding what it is doing. The default backuptargets had a directory in it that I was not backing up and I was like wow I did not think of that and left it. The thing I really liked was that icame with a very sensible default rotation already in place Oh and in response to footnote 14 I call 07:15 US Eastern
Chapter 07: Restoring Archives
This chapter just like it says is all about retoring an archive. It walks you through restoring everything from a single file to a complete archive. It explains how the restore relative to the directory it is run from and how to change that.
Chapter 010: Full Backup and Restoration
Finaly Michael walks you through planning your disaster recovery. He also delivers the wisdom that “Untested backups are not backups.” He the walks the reader through a complete dister recovery.
Best quote about Tarsnap from Colin Percival himself:
“The best thing about [Tarsnap] is that it will do whatever you tell it to do. The worst thing is that it will do whatever you tell it to do.”
Colin Percival blog
http://www.daemonology.net/blog/
Tarsnap commands
tarsnap-keygen –keyfile /usr/local/etc/tarsnap.key –user [YOUR TARSNAP USER] –machine [YOUR SERVER]
tarsnap -c -f etc$(date +-%Y%m%d) /etc/
tarsnap -c -f var$(date +-%Y%m%d) /var/
tarsnap -c -f home$(date +-%Y%m%d) /home/
tarsnap –fsck # this will restore the cache which is needed to restore anything else
tarsnap -d -f [ARCHIVE TO BE DELETED]
tarsnap -t -f [ARCHIVE TO LIST]
tarsnap -x -f [ARCHIVE TO BE RESTORED]
tarsnap –list-archives
tarsnap –print-stats
BACK SCRIPT
#!/bin/bash
tarsnap -c -f etc$(date +-%Y%m%d) /etc/
tarsnap -c -f var$(date +-%Y%m%d) /var/
tarsnap -c -f home$(date +-%Y%m%d) /home/
MY TARSNAP CONFIG FILE
vim /usr/local/etc/tarsnap.conf
### Recommended options
# Tarsnap cache directory
cachedir /usr/local/tarsnap-cache
# Tarsnap key file
#keyfile /root/tarsnap.key
keyfile /usr/local/etc/tarsnap.key
# Don’t archive files which have the nodump flag set
nodump
# Print statistics when creating or deleting archives
print-stats
# Make those stats more readable
humanize-numbers
# Create a checkpoint once per GB of uploaded data.
checkpoint-bytes 1G
# Excluding these directories
exclude /var/cache
exclude /var/log/secure
exclude /var/log/btmp
### Other options, not applicable to most systems
# Aggressive network behaviour: Use multiple TCP connections when
# writing archives. Use of this option is recommended only in
# cases where TCP congestion control is known to be the limiting
# factor in upload performance.
#aggressive-networking
# Exclude files and directories matching specified patterns
#exclude
# Include only files and directories matching specified patterns
#include
# Attempt to reduce tarsnap memory consumption. This option
# will slow down the process of creating archives, but may help
# on systems where the average size of files being backed up is
# less than 1 MB.
#lowmem
# Try even harder to reduce tarsnap memory consumption. This can
# significantly slow down tarsnap, but reduces its memory usage
# by an additional factor of 2 beyond what the lowmem option does.
#verylowmem
# Snapshot time. Use this option if you are backing up files
# from a filesystem snapshot rather than from a “live” filesystem.
#snaptime
Tech News:
Time: 1:44:00
News Content Goes Here!
Security corner
Does Windows 8 pull wifi keys from the cloud?
https://social.technet.microsoft.com/Forums/windows/en-US/4017236a-f6eb-4ad1-89ec-026474f11f5e/does-windows-8-pull-wifi-keys-from-the-cloud?forum=w8itpronetworking
Windows 8 Feature Focus: Settings Sync
http://winsupersite.com/windows-8/windows-8-feature-focus-settings-sync
Convention Scene:
Time: 2:00:00
*** Mary Put Convention Scene notes here ***
Listener Feedback:
show (at) smlr.us or 734-258-7009
Time: 2:05:15
Outtro Music
Time: 2:14:30
404 not found, Album shaken, not stirred by Los as schrenza by a.m.c.hartmutschedler
https://www.jamendo.com/en/track/961154/404-not-found
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