Episode 093 – Welcome back Again Kevin!

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Total Running Time: 1:33:29

Un-edited Live session – http://www.youtube.com/watch?v=1_D8XyXMX0s&feature=share&list=UUyNJoeK7fk61qlVJJK15hvQ

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Summary

Kernel News: Mat
Time: 9:10
Distro Talk: Tony
Time: 12:00
Kevin O’Brien from OLF
Time: 20:30
Tech News:
Time: 55:45
Toolbox
Time: 1:01:50
Listener Feedback
Time: 1:14:10
Outtro Music
Time: 1:27:55

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Intro:

Tony Bemus, Mat Enders, and Mary Tomich
Sound bites by Mike Tanner

Kernel News: Mat

Time: 9:10

Release Candidate:
On Sun, 14 Jul 2013 16:57:23 PDT
Linus Torvalds released kernel 3.11-rc1
Here is what he had to say about it:

“It’s been two weeks, and the merge window has closed. If I missed anything, holler, but I don’t have anything pending that I am aware of.

This merge window was smaller in terms of number of commits than the 3.10 merge window, but we actually have more new lines. Most of that seems to be in staging – a full third of all changes by line-count is staging, and merging in Lustre is the bulk of that. Let’s see how that all turns out, I have to say that we don’t have a great track record on merging filesystems through staging.

Ignoring the lustre merge, I think this really was a somewhat calmer merge window. We had a few trees with problems, and we have an on-going debate about stable patches that was triggered largely thanks to this merge window, so now we’ll have something to discuss for the
kernel summit. But on the whole, I suspect we might be starting to see the traditional summer slump (Australia notwithstanding).

Despite being a bit smaller than the last merge window, it’s not like this was a _tiny_ one, and so as usual I’m only summarizing with the normal -rc1 mergelog: and as usual the people credited here are *not* the people who actually wrote the code (although in some cases that is true), they are the people who I merged the code from.

Hey, let’s all start testing,”
–Linus Torvalds

Mainline:
3.11-rc1

Stable Updates:
None

Kernel Developer Quote:
None

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Distro Talk: Tony

Time: 12:00

Distrowatch.com

• 7-16 – PCLinuxOS 2013.07 “KDE MiniMe”, “LXDE”, “MATE” – Featuring a minimalist KDE, as well as LXDE and MATE desktops
• 7-16 – Webconverger 21.0 – Debian-based distribution for Internet-only kiosks and similar deployment
• 7-17 – Salix OS 14.0.1 “Xfce” – Slackware-based distribution featuring the latest Xfce desktop environment
• 7-18 – OLPC OS 13.2.0 – Fedora-based Linux distribution developed under the initiative of the One Laptop Per Child (OLPC) project to provide children in developing countries with low-cost laptops
• 7-20 – DEFT Linux 8 – Lubuntu-based distribution and live DVD featuring a collection of open-source tools for digital forensics and penetration testing

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Kevin O’Brien from OLF

Time: 20:30

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Tech News:

Time: 55:45

The H Closes Up Shop

They stated the reason they are closing down is due to an inability to monetise the traffic into a working business model. Even though they produced many high quality stories, and were one of my goto places for ideas, they just couldn’t turn that corner. They will be missed, their last published story can be read here (http://www.h-online.com/features/The-Final-H-Roundup-1919816.html), it is titled “The Final H Roundup. The story is an alltime top 10 list of stories published on The H.

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The Toolbox

Time: 1:01:50

Nifty Stuff With ssh

Here is our first situation:
We have a PC at home called “mypc”. We want to connect to a computer at the office called “work”, but we are only allowed to connect to a jump server called “gate”. Usually you would take two jumps to get there. First you would connect from “mypc” to “gate”, and then from “gate” to “work”.

Let’s take a look at how an ssh tunnel can help:
On “mypc” we run this command:

ssh -l myuserid -L 7777:work:22 gate cat -

This means: open an ssh connection as user myuserid to host “gate” and run the command cat -. For however long as the session is open, redirect all traffic directed to port 7777 on the local machine to port 22 on machine “work”.

Now we can use any SSH command (ssh, scp, sftp) to connect directly to work through the tunnel.
For example:

ssh -p 7777 localhost uname -a

scp -p -P 7777 localhost:data/file1.txt

sftp -o Port=7777 localhost

How it works:

You initiate an ssh process on the local machine “mypc” that creates an ssh connection with the sshd server on “gate”. It uses the default ssh port 22 on the server side. In addition, because we have used the -L option, the local ssh process accepts local connections to port 7777 and sends all data received on this port through to the connection to gate with some marking “this is from tunnel 7777”. The jump server “gate” has been informed through the -L option that, whenever it receives data marked with “this is from tunnel 7777”, it has to open a connection to the computer known as “work” on port 22 and forward the data to it.

Second situation we run rsync over an untrusted network e.g. the internet:

To use rsync over ssh, pass it the -e switch, like this:

rsync -ave ssh user@remotemachine:/rmt/dir/tosync/ /lcl/dir/tosync/

Let’s break that command down for you:

rsync = A program that synchronizes files and directories from one machine to another
-ave = -a archive mode (preserves all of the attributes of the files and directories), -v increase verbosity (with one v it list all the files as they synchronized), -e specify the remote shell to use (in this case we are telling it to use ssh)
ssh = The shell/service we are using to connect
user@ = The user on the remote machine we are connecting to
remotemachine = Can be anything that will connect you to the correct machine e.g. hostname, ip address
:/rmt/dir/tosync/ = The remote directory to be synchronized
/lcl/dir/tosync/ = The local directory to be synchronized

Notice the trailing / on the remote and local directories.  What this does is copies the contents of the directory but not the directory.  As an example let’s say you are syncing /home/menders/ to /local/backup/.  The /local/backup/ directory will contain everything inside of /home/menders/ but not the parent directory menders.  If the trailing slashes were left off you would have a directory called menders inside /local/backup/ called menders containing everything that is inside the remote directory menders.

By default, rsync only copies files and directories, but does not delete anything from the destination copy when they are removed from the source.  If want the directories to be exact copies then you need to include the option:

--delete = Will delete files from the destination that have been deleted on the remote machine

By default it will delete the files before transfer so as to make room and speed the process.

Using ssh to run rsync over encrypts the data over the network and also takes advantage of any trust relationships you already have established using ssh client keys.

SSH Tunnel + SOCKS Proxy Forwarding = Secure Browsing
http://embraceubuntu.com/2006/12/08/ssh-tunnel-socks-proxy-forwarding-secure-browsing/

ssh -D 1080 username@ip-address-of-ssh-server


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Listener Feedback:

show (at) smlr.us or 313-626-9140
Time: 1:14:10

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Outtro Music

Time: 1:27:55
Nine Inch Nails – 31
http://archive.org/details/nineinchnails_ghosts_I_IV

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