Now that you have completed Assignment 1 and have a working sandbox Linux system installed, it’s time to cover the basics.

First, when I started using Linux, I got a boxed set of RedHat that included a nice cheat sheet sticker to go on a keyboard wrist rest. In lieu of that, I just saw this posted today. I recommend you keep it bookmarked and perhaps printed out for reference: Linux Command Shelf Cheat-Sheet. There’s a PDF for download on that site. I also recommend you somehow (RSS or Facebook) subscribe to NixCraft. I still regularly learn useful things from that blog.

Now, when taking care of a Linux (or other *NIX) system, you’re often going to need to download and extract file archives. Typically these are either singly-zipped files (.gz or .bz2 from gzip and bzip2, respectively), or so-called “tarballs” (.tar, .tar.gz, .tgz, .tar.bz2, etc). Tarballs are created with the tar program, whose name comes from Tape ARchive. The additional suffixes indicate that the tarball has been compressed in some way. In other words, a simple .tar file contains a bunch of files all rolled up into a single archive, but not compressed, while .tar.gz (.tgz for short) files have additionally been zipped up in some fashion. Incidentally, tar is also still used to write files to tape, if that’s your thing.

The best way to get a file for download from the command-line (which I will focus on almost entirely in this series) is wget. So, open up a terminal window. You should have a simple prompt waiting for your input. Check to see whether you have wget by typing

which wget

The which command searches through all of the directories on your PATH, an environment variable that tells the shell where to find programs, for the command you list, in this case wget. It’s a good way to check for the presence of a program on a system. If that doesn’t work, but you think it’s around somewhere, you can sometimes use locate, but we’ll not cover that today.

Now, if you have wget, you should get in return the full path to the program, something, like /usr/bin/wget. If so, you can proceed to the next step where it says ‘Downloading a file with wget’.

If not, the utility will print nothing. I tried a made-up program called ‘snarfblat’:

brock@gamont:~$ which snarfblat
brock@gamont:~$

Here’s a successful which call for wget:

brock@gamont:~$ which wget
/usr/bin/wget
brock@gamont:~$

If you don’t have it, try sudo apt-get install wget on a Debian-based distribution or sudo yum install wget on a RedHat-based distribution. If you’re not set up with sudo, we will cover that later. For now become root with su - followed by the root password, and then run the above commands without the sudo at the beginning. Type exit or press Ctrl-D to exit the root shell once you have installed it. Double-check that it’s now installed by calling which wget again. If you get stuck, please email me or comment here so we can take care of it and you can continue.

Downloading a file with wget

For this tutorial, I’m going to have you download a sample tarball that I have created. It contains a bunch of directories and files with various names and contents. We will use it in this assignment and later assignments to practice command-line basics.

For now, go to a terminal (I recommend you make a directory for this like mkdir ~/sywtbals, where ~/ is a shortcut for specifying your home directory. In my case that is /home/brock. Then change to that directory: cd ~/sywtbals.

Now, run wget to pull down the file.

wget http://blog.brocktice.com/sywtbals/1.tgz

It should look like this:

brock@water:~/sywtbals$ wget http://blog.brocktice.com/sywtbals/1.tgz
--2013-05-05 17:30:33--  http://blog.brocktice.com/sywtbals/1.tgz
Resolving blog.brocktice.com... 209.188.113.105
Connecting to blog.brocktice.com|209.188.113.105|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 215040 (210K) [application/x-gzip]
Saving to: “1.tgz”

100%[======================================>] 215,040      259K/s   in 0.8s    

2013-05-05 17:30:34 (259 KB/s) - “1.tgz” saved [215040/215040]

brock@water:~/sywtbals$

Give yourself a self-high-five if you noticed I changed machines in the middle of this post from gamont to water.

Now that you’ve got the file, let’s take a look at it with ls, the file-listing tool:

brock@water:~/sywtbals$ ls -l 
total 212
-rw-r--r-- 1 brock brock 215040 May  5 13:40 1.tgz
brock@water:~/sywtbals

I used the -l for the ‘long’ listing that shows details about each file. This shows us a few interesting things. One is the permissions:

-rw-r--r-- brock brock

This tells us the permissions for the user, group, and everyone else. A file may only have one group and one user assigned to it. There’s SELinux (Security-Enhanced Linux), the NSA’s enhancements to make Linux permissions more fine-grained, but honestly I don’t understand SELinux well enough to do more than turn it off, so I’m not going to discuss it here.

So, in this case the user has read and write permissions, the group has read permissions, and everyone else also has read permissions. The user is brock and the group is brock. Note that even though the user and group names are the same they are totally separate. One represents a userid, and the other represents a groupid. Observe the use of the id command to elaborate:

brock@water:~/sywtbals$ id
uid=1000(brock) gid=1000(brock) groups=1000(brock),24(cdrom),25(floppy),27(sudo),29(audio),30(dip),44(video),46(plugdev),100(users),108(netdev),109(bluetooth),112(fuse),115(scanner),120(libvirt),1001(family)
brock@water:~/sywtbals$

Here you can see that (and again, this is just a coincidence because I was the first user added to the system), the user id brock is 1000, and the group id brock is also 1000. However, the group id brock could just as easily be 2005 or something.

Let’s say this file is somewhat secret and I don’t want anyone else (except root of course) on the system to be able to read it. We’ll change it like this:

brock@water:~/sywtbals$ chmod go= 1.tgz
brock@water:~/sywtbals$ ls -l
total 212
-rw------- 1 brock brock 215040 May  5 13:40 1.tgz

What I did is to tell chmod to set the group and other permissions to be equal to nothing. As a result, only the user has any permissions at all.

On the other hand, what if we want to allow anyone on the system to read and write the file?

brock@water:~/sywtbals$ chmod go+rw 1.tgz 
brock@water:~/sywtbals$ ls -l
total 212
-rw-rw-rw- 1 brock brock 215040 May  5 13:40 1.tgz
brock@water:~/sywtbals$

You can also use numerical codes to set permissions. All I ever remember about that offhand is that 0 means nothing and 7 is everything. I prefer the other notation, but you can look it up. A common 4-letter admonition you’ll see as a Linux sysadmin is RTFM — read the fucking manual.

Usually you can find the so-called manfile for a program or configuration file like this:

man chmod

This will show the output in the system pager, a program that pages through a text file. Historically this was normally a program called, sensibly, more. Later, an improved program called less replaced it. UNIX humor — less is more. Anyway, there are only four things you need to know to get around less reasonably well. The q key quits. The spacebar moves to the next page. And the / key starts a search. The Esc key gets you back to the main mode. There’s a lot more you can do with less, but those four things will make up 99% of your less usage.

The most important thing you can do with the / search in many manpages as a beginner is to find the Examples section, if there is one. It will usually contain examples of what you’re trying to do. Of course you can also RTFM. Here’s me searching for the examples in the chmod manpage. Note the /examples at the end.

CHMOD(1)                         User Commands                        CHMOD(1)

NAME
       chmod - change file mode bits

SYNOPSIS
       chmod [OPTION]... MODE[,MODE]... FILE...
       chmod [OPTION]... OCTAL-MODE FILE...
       chmod [OPTION]... --reference=RFILE FILE...

DESCRIPTION
       This manual page documents the GNU version of chmod.  chmod changes the
       file mode bits of each given file  according  to  mode,  which  can  be
       either a symbolic representation of changes to make, or an octal number
       representing the bit pattern for the new mode bits.

       The format of a symbolic mode is  [ugoa...][[+-=][perms...]...],  where
       perms  is  either zero or more letters from the set rwxXst, or a single
       letter from the set ugo.  Multiple symbolic modes can be  given,  sepa‐
       rated by commas.

       A  combination  of the letters ugoa controls which users' access to the
       file will be changed: the user who owns it  (u),  other  users  in  the
/examples

Unfortunately, when I hit the Enter key after typing /examples I was greeted with Pattern not found (press RETURN). So I’ll have to properly RTFM. I press the spacebar to scroll down. (Arrow keys and page up/down can also be used to navigate.) Eventually I find this documentation on the octal numerical codes:

       granted  to  users  that are in neither of the two preceding categories
       (o).

       A numeric mode is from one to  four  octal  digits  (0-7),  derived  by
       adding up the bits with values 4, 2, and 1.  Omitted digits are assumed
       to be leading zeros.  The first digit selects the set user ID  (4)  and
       set group ID (2) and restricted deletion or sticky (1) attributes.  The
       second digit selects permissions for the user who owns the  file:  read
       (4),  write  (2),  and  execute  (1); the third selects permissions for
       other users in the file's group, with the same values; and  the  fourth
       for other users not in the file's group, with the same values.

       chmod never changes the permissions of symbolic links; the chmod system
       call cannot change their permissions.  This is not a problem since  the
       permissions  of  symbolic links are never used.  However, for each sym‐
       bolic link listed on the command line, chmod changes the permissions of
       the pointed-to file.  In contrast, chmod ignores symbolic links encoun‐
       tered during recursive directory traversals.

SETUID AND SETGID BITS
       chmod clears the set-group-ID bit of a regular file if the file's group
       ID  does  not  match the user's effective group ID or one of the user's
       supplementary group IDs, unless the user  has  appropriate  privileges.
 Manual page chmod(1) line 44

There you go, the numerical codes are read = 4, write = 2, and execute = 1. Execute means that if it's a script or a program, it can be run, or if it's a directory, you can navigate (change directory or cd) into it. Anyway, to set read/write for user and group, and nothing for everyone else, you'd use (4+2=6)(4+2=6)(0) or chmod 660.

So, now that we've beaten the permissions thing to death. Just a few other notes. In this output:

-rw------- 1 brock brock 215040 May 5 13:40 1.tgz

The last few bits are the file size (215040 bytes) and file modification time, ending with the filename. You can get a handy "human-readable" size using the -h for human flag like so:

brock@water:~/sywtbals$ ls -lh 1.tgz 
-rw-rw-rw- 1 brock brock 210K May  5 13:40 1.tgz
brock@water:~/sywtbals$

I usually use the -h when doing a detailed listing. Because it rounds, however, sometimes you may want to omit the -h to see if a file size matches, has changed, etc.

OK! Let's extract this sucker. We'll use a tar command to extract. First, let's get a preview of the file contents. Nice people generally put everything to tar in a directory first, so that the directory extracts nicely and doesn't make a mess. Sometimes, (and occasionally even with good reason), people will put all the contents of the tar right at the top level, and extracting without knowing that will make a big mess. (I'll cover a quick tip to fix that when we get to pipes. Don't let me forget.).

To get a preview of the file contents, we use the t flag to tar:

brock@water:~/sywtbals$ tar tvf 1.tgz
drwxrwxr-x brock/brock       0 2013-05-05 13:31 1/
drwxrwxr-x brock/brock       0 2013-05-05 13:30 1/sequential/
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential/sequential_file_85
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential/sequential_file_34
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential/sequential_file_60
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential/sequential_file_43
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential/sequential_file_30
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential/sequential_file_64
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential/sequential_file_11
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential/sequential_file_77
...
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential_padded/sequential_file_00093
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential_padded/sequential_file_00049
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential_padded/sequential_file_00013
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential_padded/sequential_file_00068
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential_padded/sequential_file_00018
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential_padded/sequential_file_00055
-rw-rw-r-- brock/brock      12 2013-05-05 13:31 1/sequential_padded/sequential_file_00005
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential_padded/sequential_file_00098
-rw-rw-r-- brock/brock      12 2013-05-05 13:31 1/sequential_padded/sequential_file_00001
-rw-rw-r-- brock/brock      13 2013-05-05 13:31 1/sequential_padded/sequential_file_00026
brock@water:~/sywtbals$

The command tar tfv 1.tgz can be broken down as follows: tar is the program, t tells it to test the file, f tells it it's getting a filename for input (1.tgz in this case), and v means verbose, in that it prints out all the names of the files being extracted. You'll always need f to extract a file. The philosophies on v vary. Some people say using it causes errors to get lost in the shuffle and go unnoticed. Others like to see which files are being extracted. If you do a run like this with t first, then you can go ahead and do the actual extraction later without v and see any errors.

I'm a nice guy, so I put the contents in a directory called 1. (I'm also an idiot, this is Assignment #2, but I digress). So let's go ahead and extract the file.

brock@water:~/sywtbals$ tar xf 1.tgz 
brock@water:~/sywtbals$

In this case I omitted the v option, and changed from test mode to extract mode. tar followed the UNIX convention of outputting no message at all if everything worked correctly.

Do a quick listing on the created directory just to double-check:

brock@water:~/sywtbals$ ls -l 1
total 8
drwxr-xr-x 2 brock brock 4096 May  5 13:30 sequential
drwxr-xr-x 2 brock brock 4096 May  5 13:31 sequential_padded
brock@water:~/sywtbals$

Looks good! Questions?

I have a bonus question. tar figured out something about our 1.tgz file and took care of it without us asking. Do you know what that is?

There is a shortage of good Linux system administrators. Some friends of mine have an interest in helping to fill that shortage, so I have finally decided to embark upon a series of blog posts based on my experience. First, let’s get some things out of the way.

Qualifications

There are plenty of linux sysadmins out there, with varying degrees of experience, and varying methods and opinions. I do not claim to be the leading expert on the subject, I’m just trying to write up what I do know. Constructive comments and suggestions are welcome. People telling me what an idiot I am will have their comments deleted. That said, here are my qualifications regarding Linux system administration. I offer them both to show you I’m not just making this stuff up, and also to give you one example of how people learn Linux sysadmin skills without a formal education or certificate program.

• I started using Linux in 1998 with a Linux for Dummies book and the included copy of Red Hat 4.something.
• I’ve run Linux servers in some form and with varying degrees of success since college in 2000.
• I took about half of a computer science major in college as a double-major until I dropped that to focus on research, next point.
• When I joined a computational science research lab as an undergrad in fall of 2002, I took over the Linux/Irix system administration for the lab, and started porting old Irix applications to run on Linux.
• When our lab moved to Johns Hopkins University after Hurricane Katrina, I set up our compute nodes (formerly run by a Tulane sysadmin) as a high-performance computing (HPC) cluster. This was the real beginning of my HPC experience.
• Shortly thereafter, we ordered a new cluster for the lab. I handled the process of deciding specifications, working with vendors to get quotes and negotiate the deal, and then running the cluster (from Penugin Computing) once it was delivered.
• After graduating, I did some consulting work for Penguin Computing on a variety of HPC tasks. I think this went pretty well based on the feedback I got from Penguin and end customers.
• At this point I’m running a high-performance cluster in my garage for my work at CardioSolv Ablation Technologies, and also running my own server hosting this blog and a bunch of other stuff.

Disclaimers

• Just to reiterate: I do not claim to be the leading expert on the subject, I’m just trying to write up what I do know.
• With Linux, there are usually a minimum of three different ways to do a certain thing or solve a different problems. Every time I work next to another sysadmin I learn stuff from them, and at least a few times they’ve learned things from me. Nothing anyone writes about how to do stuff is gospel.
• I will not be responsible if you destroy systems or data from following my instructions without understanding them.

With that out of the way, let’s get started.

Welcome to Linux

There are many books you can buy and sites you can read that will give you a history of Linux and an overall philosophy for how it works, etc etc. I’m going to assume if you’re reading this that you already know all that stuff and jump right in. In my experience, the best way to learn how to be a Linux sysadmin is to try to make things work. You’ll learn a lot in the process, so I’m going to do this as a series of assignments.

Assignment 1

If you haven’t already, set up a Linux computer or a virtual machine (using VirtualBox, VMware, or the like), strictly for practicing on. I recommend you start with Debian or CentOS, or possibly Ubuntu Server. I prefer Debian, but most popular Linux distributions are based on either Debian or RedHat, so learning either of those will get you off to a good start. To be good at Linux system administration, you’ll eventually need to know your way around both. We’ll get to that (and some other interesting distributions like Gentoo) in later assignments.

Set up this machine with three partitions: /, /boot, and /home. Leave a minimum of 200MB for /boot, 20GB for /, and the rest assign to /home.

When done, you should be able to log in as your primary user (i.e. brock) as well as root, the god-like default system administration account.

Please reply or email me with any questions.

Since moving to Northern New Mexico, living only a 2-hour drive from Philmont (and make no mistake, my memories of Philmont made me receptive to moving here), I’ve kept meaning to drive out there and see it again, but have never made the time.

This spring, while skiing in Taos, I got a breathtaking view of the mountains to the East from near Kachina Peak, and I could swear that one looked like that same Baldy Mountain I climbed, albeit covered with snow. Just this morning I finally pulled up Google Maps and confirmed that it was, indeed, the same peak. Philmont resides just over the mountains from Taos. I may not have made it back there to visit yet, but at least I’ve now laid eyes on Baldy Mountain and Philmont once again.

I’m happy to report that with the InfiniBand hooked up as of yesterday I can now scale across all 6 IB-equipped compute nodes with approximately linear scaling. Unfortunately the older single-data-rate (SDR) hardware I got for ‘cheap’ from eBay didn’t produce the kind of dramatic reductions in latency I expected compared to gigabit Ethernet. I expect for that I’ll really need to upgrade to QDR IB at some point, but I’ll also probably want faster machines at that point. Total cost for the IB upgrade (24-port Cisco Topspin switch $350, 7 Mellanox HCAs for $39.90/ea – $279.30, 7 CX4 cables with latch connectors at $16.00/ea – $112.00) was $741.30. I intend to add some posts later with more details of the setup, as I know there some interest out there in setting up cheap IB hardware at home.

I have created a github for this here. If you have patches please submit pull requests!

UPDATE: I continue to update the kernel as more fixes make it into git. You can check all of the Pixel-related files I’m posting in this Drive folder.

UPDATE 2013-03-27: New kernel with fix for the audio pops, see my G+ post from today.

The Chromebook Pixel is a very nice (if expensive) piece of hardware, designed to run Chrome OS, which is a variant of Linux. Since being noted as favored by Linus Torvalds, inventor and lead maintainer of Linux, support for the various Pixel hardware components has rapidly been added to the kernel git repository.

Not everything is working great just yet, but all of the essential features are working. Here’s a walkthrough that I hope will be sufficient, based almost entirely on other people’s work and howtos. I’ll link to those where I can. Several Google software engineers have been helpful on Google+, and a bunch of work has been done by Linux kernel maintainers.

This was my starting point: DaveM’s howto in his Linux git repo

1. Get a chromebook pixel
2. Enable developer mode
3. Download the Debian Wheezy netinstall image (yes, it supports the wifi in the installer) (here)
4. Boot from the installer (Ctrl-L at boot screen, escape when it says to press escape to choose a boot device, choose your USB drive with the Debian installer)
5. Install as normal to the internal SSD. I used LVM/encryption and it worked just fine. When you reboot, pull the USB drive and it should boot from the internal SSD.
6. Once booted, the trackpad will not work. A USB mouse will work just great. Download and install my build of the 3.9-rc1 kernel (.deb files and config, full source) built from Linus’ merging of patches and configured with help from Benson Leung
7. To your /etc/modules add:

   ath9k
   atmel_mxt_ts
   chromeos_laptop
   tpm_tis force=1 interrupts=0
   

   Those are the modules for the wifi, the touchpad (both the atmel and chromeos_laptop), and the tpm chip, that to keep it from rebooting when you try to suspend (thanks Duncan Laurie!).

8. This is no longer necessary with the updated downloads. To your /etc/rc.local, above exit 0, add echo TSCR > /proc/acpi/wakeup. This is a hack to keep it from waking right up after going to sleep (thanks, Benson Leung!)
9. This appears not to be necessary, actually Create a file called 01i8042 in /etc/pm/sleep.d to properly sleep and wake the keyboard on suspend. It should have this as its contents.

   #!/bin/sh
   
   ###############################################################################
   # Pm-utils script to unbind i8042 on hibernate/suspend and
   # bind it on thaw/resume.
   #
   # Copyright: Copyright (c) 2009 Nicolay Doytchev
   # License:   GPL-3
   ###############################################################################
   
   ###############################################################################
   # INSTALL:
   #   1. Copy this script to /etc/pm/sleep.d/
   #   2. Make it executable:
   #       sudo chmod +x /etc/pm/sleep.d/01i8042
   #
   # UNINSTALL:
   #   1. Delete the script from /etc/pm/sleep.d/
   #       sudo rm /etc/pm/sleep.d/01i8042
   ###############################################################################
   
   case "$1" in
       hibernate|suspend)
           echo -n "i8042" > /sys/bus/platform/drivers/i8042/unbind
       ;;
       thaw|resume)
           echo -n "i8042" > /sys/bus/platform/drivers/i8042/bind
       ;;
   esac
   

   Make it executable. Found this here

10. You may need to install the firmware-atheros package for the bluetooth to work, which may require adding non-free to the end of the deb lines in /etc/apt/sources.list

I think that’s it, but it’s always hard to correctly recreate these things after the fact without redoing it (and I’ve spent enough time on this already). Let me know if you have any problems or improvements, or go comment on Linus’ G+ post about it.

I want to add a special thank-you to Linus Torvalds for posting about his updates on Google+.

EDIT: More stuff
First, if you hate tap-to-click like me, here’s an xorg.conf with the correct dpi setup and multi-finger click.

Here is a folder containing all the relevant files and info (plus my other configs I decide to upload) discussed in this post and the comments.

Also, FYI the keyboard backlight does not come on after suspend right now.

EDIT 2013-03-11 20:33 MDT: By the way, if you run i3 or some other nerdy window manager like me, and you forgot how to make Debian sleep when the lid is closed, you just need to uncomment the appropriate line in /etc/default/acpi-support.

Disclaimers made, here we go. I think that to succeed in any endeavor, you need three things: motivation, aptitude, and skill. Briefly, I will define these as I think of them.

• Motivation: The inherent drive to do something. This could be for any reason.
• Aptitude: The inherent or natural ability to do something.
• Skill: The learned ability to do something.

I have the urge to make a triangle diagram, but I’m going to fight it for now. Basically, you won’t want to do something unless you are so motivated, which is something of a tautology. You may not be able to unless you have the aptitude. A good example of aptitude is the proverbial one-legged man in the ass-kicking contest. No matter how much he practices, he’s still going to have a very hard time. Finally, skill is the development that occurs on top of aptitude. There’s a common misconception that Mozart was simply able to play the piano and compose because he was a whiz. He may have had a ton of aptitude, but he also had a skilled composer and musician for a father, who drilled him from an early age on the skills required to realize that aptitude.

That last point is what really got me thinking about this in the first place. I was a smart kid. I had a lot of aptitude at certain things. I didn’t learn until I got to college that I’d never really learned to properly develop a skill to realize that aptitude. I think there’s a common cultural perception in America, or maybe even the West in general, that some people are just naturally really good at something, and therefore they end up excelling at it. This is a really poisonous notion, because then when people try to realize an idea they become frustrated, decide that they’re just “not any good at it” and quit. Culturally I wish we could shift to really recognize that a skill must be developed in order to realize aptitude.

Let me give you an example that I hope applies to you and will illustrate what you want. It could really apply to any artistic endeavor — this problem seems to be most manifest with regard to art. If, as a kid or even as an adult, you had a vision of something you wanted to draw, and then you sat down to try to draw it, you probably found that you could not make what was in your head appear on the paper. To me that artistic vision was part of the aptitude, but the skill was missing. Obviously if you were trying, you had the motivation. If you were like me (at least at one point), you may have become frustrated and given up. This is because your motivation was being channeled into merely trying, not developing the necessary skill, perhaps because you believed that you just weren’t naturally good enough at it. If drawing doesn’t apply to you, maybe it was playing guitar, or playing basketball, or learning to program.

Before I close this initial essay on this topic, let’s examine what happens when you only have two of the three components of this triangle-I-will-not-draw:

• Motivation and Aptitude: Skill is lacking, and so as in the example above, this often results in frustration. If you recognize that skill must be developed, then that frustration can be channeled productively.
• Aptitude and Skill: No motivation, so you never get it done. Could be considered “wasted talent”, but there are many good reasons to not be motivated to do something.
• Motivation and Skill: This is tough. This is the one-legged man in the ass-kicking contest. Like the first situation, it’s going to lead to frustration. In this case probably the only reasonable response is acceptance.

So there you have it, motivation, aptitude and skill. The next post on this topic will probably relate these three concepts to the concept of a “challenge”. I welcome additional thoughts as well as criticism.

Apple has somehow (and I don’t pretend to understand this) extended the protocol to use both a username and a password, including passwords longer than 8 characters.

Someone provided a patch to the Vinagre project to fix this over six months ago, but they blew it off. I went ahead and patched the source and rebuilt the package on my x86_64 Debian Wheezy/Sid system. You can download it from here, and go pester the developers to accept the patch in mainline.

For the last couple of years I’ve been running a Windows virtual machine in VMWare Workstation primarily so that I can use my scanner and the included OCR features (turn scans into text).

Recently, I’ve been having a lot of trouble with VMWare Workstation, and I run libvirt/qemu-kvm on my web server, so I decided to try it on my workstation as well. It works pretty well for Windows 7, not a fast as VMWare when it worked properly, but the scanner will not function correctly using it.

Last time I looked into using the S1500 on Linux I found almost nothing. I could scan stuff but it wasn’t very useful for a paperless office workflow, the whole reason I have such a scanner.

I am happy to say that, on Debian Wheezy/Sid, gscan2pdf with the libsane-perl backend and tesseract for OCR seem to work nicely. Some caveats:

• I downloaded the newest version of gscan2pdf and installed it. At the moment that is 1.0.6.
• The ‘Page Options’ tab of the ‘Scan Document’ window only works properly when I choose options that don’t make much sense. I selected ‘ADF Duplex’ in the ‘Standard’ tab, and then in the ‘Source document’ section of the ‘Page Options’ tab, I have selected ‘Single-sided’ and ‘Side to scan: Facing’. Otherwise, the page numbers come out strange. I do still get double-sided scanning, though.

I couldn’t find a lot about this on the web, so I hope it helps someone else in my position. Happy scanning!

EDIT 2012-10-28 Strangely enough, I was able to get the scanner working just fine in my Windows VM using Spice USB redirection. It’s good to have the fallback, but I’ll try to stick with Linux, it’s much more convenient and removes a dependency.

• Take 2-5 mg of fast-dissolving or liquid melatonin about 30 minutes before sleep.
• Do this when you’re ready to sleep on the red-eye flight
• Do this every day at your destination for the first 3-4 days
• Maybe avoid caffeine and alcohol
• Do NOT take melatonin earlier in the day, or at any other day or time beside what is listed above. This includes not taking any in the days before your flight.
• Try to get dark when you should be sleeping and light when you should be awake (by the time zone you’re adjusting to).

That’s it. Lots of long-winded discussion exists on the internet. Many abstracts tease at this information but don’t give it. But now you have it. Happy travels.