miscfits

Append authorized_keys the lazy way

2009-10-30T15:26:00.001-07:00

*update. No-no, THIS is the lazy way: man ssh-copy-id

ssh root@server "cat >>~/.ssh/authorized_keys" <~/.ssh/id_rsa.pub

The Stages of NetBooting

2009-10-30T10:49:00.000-07:00

Your BIOS and network card initiate a broadcast to get information about Boot sources
Your DHCP server responds with information about how to boot
Your computer downloads a small file over TFTP and begins a boot process
Your Operating System is mounted over NFS and all your files are served over your 100Mbit network card
Eventually you get tired of the slowness of certain things so you put your OS on a 16GB thumbdrive, and simply mount /home over NFS
Eventually you get tired of filesystem corruption and you put your OS onto your USB backup hard drive.
Eventually you get tired of USB problems with suspend and you buy a hard drive
Now you keep everything on your internal hard drive except for your large movie/music/picture collections which you mount via NFS when you want them.
Eventually you get tired of that and you keep everything on your internal hard drive and just back it all up to your fileserver.
Life is good again
Then you setup Unison. Stay tuned for our next post; "The Stages of Unison"

Verizon Wireless Website Linux solution

2009-10-08T22:28:00.000-07:00

My Verizon is temporarily unavailable

Annoying, isn't it? This is the message you might get if you are using firefox, iceweasel, or Epiphany, or anything else combined with Linux. Very, very, frustrating. Well, here is the solution as of 10/8/2009: Use Spanish. Seriously, click the Español link at the top of the page, and then log in. Come on, don't tell me you can't find Entrar. Once you are signed in, just click English again and you are good to go. Or, learn Spanish. Why not?

normalize all your movie audio on-the-fly with ALSA

2009-09-13T20:41:00.001-07:00

I have a pretty large collection of ripped dvd movies. Invariably, they all have different volumes, which can be very annoying. I was just about to use mencoder to re-encode all the audio with normalized audio... and then I thought there must be a better way. Sure enough, there is: http://alsa.opensrc.org/index.php/FAQ#Is_there_an_alsa_plugin_I_can_use_to_compress_or_normalize_my_audio_output_volume.3F

So I copied the section below into /etc/asound.conf:

pcm.ladcomp {
      type plug
      slave.pcm "ladcomp_compressor";
  }
 pcm.ladcomp_compressor {
      type ladspa
      slave.pcm "ladcomp_limiter";
      path "/usr/lib/ladspa";
      plugins [
          {
              label dysonCompress
              input {
                  #peak limit, release time, fast ratio, ratio
                  controls [0 1 0.5 0.99]
              }
          }
      ]
  }
 pcm.ladcomp_limiter {
      type ladspa
      slave.pcm "plughw:0,0";
      path "/usr/lib/ladspa";
      plugins [
          {
              label fastLookaheadLimiter
              input {
               #InputGain(Db) -20 -> +20 ; Limit (db) -20 -> 0 ; Release time (s) 0.01 -> 2
               controls [ 20 0 0.8  ]
              }
          }
     ]
  }

These plugins need to be installed though: apt-get install swh-plugins
Now the tricky part, getting your programs to actually use this stuff. You have to tell your program to use the ladcomp alsa device. Mplayer and Xine are pretty easy, you can just type it in a box in the gui. However, Gnome's Movie Player (Totem) is a bit trickier. Google to the rescue: http://www.mail-archive.com/gnome-list@gnome.org/msg02589.html

Basically open Configuration Editor and change
system -> gstreamer -> 0.10 -> default) changing the key "musicaudiosink" from "alsasink" to "alsasink device=ladcomp"

All my movies seem to be nearly the same volume now. I setup xine to use it as well, and played a DVD and it seemed to be just a bit louder than movie files, so I'll have to look more into exactly what this filter is doing, maybe it is not reducing loud volume, but just cranking up low volume?

smp usb flash-on-root corruption issue

2009-09-08T13:11:00.000-07:00

I suspect (but can't really confirm) that having this 3-processor phenom chip and booting to USB flash, combined with suspend-to-ram seems to somehow result in an extremely corrupted filesystem. Booting with kernel option "nosmp" seems to completely resolve the problem... so, that is good and sucky at the same time. Aha! Hot-plug to the rescue! I just stuck this script in /etc/pm-tools/sleep.d/99cpu

#!/bin/sh

. "${PM_FUNCTIONS}"

case "$1" in
hibernate|suspend)
echo 0 > /sys/devices/system/cpu/cpu1/online
echo 0 > /sys/devices/system/cpu/cpu2/online
;;
thaw|resume)
echo 1 > /sys/devices/system/cpu/cpu1/online
echo 1 > /sys/devices/system/cpu/cpu2/online
;;
*)
;;
esac

We'll have to see if it solves the problem, but it does indeed remove my 2 processors before suspend and then adds them back again after everything is back up. Kinda sad but I don't feel like upgrading my kernel or messing around this more than I have to :-)

Debian Lenny
Kernel 2.6.26-2-686 #1 SMP

Linux Wireless Fun

2009-09-06T22:00:00.000-07:00

LinkSys WPM54G PCI wireless card:

apt-get install firmware-ralink
it should work now

edit /etc/pm/config.d/defaults
and add/change:
SUSPEND_MODULES="rt61pci"

now you should be able to suspend the computer and not hang on resume

Harbor Freight Wood Carving Tools

2009-08-29T08:06:00.000-07:00

I know Harbor Freight has cheap tools, but they are usually at least functional-- for a little while anyway. In the case of the 11 piece Wood Carving Set, however, my recommendation would be to steer clear. At $5.99, that comes out to less than 50 cents per tool. How can you possibly make a tool for "The Finest Wood Carving Applications" for only 50 cents?!?

Don't look so bad huh? Well, just wait until you try to carve something with them.

Ummmm is this a U-gouge?

How is this supposed to work?

These are going back. $6 bucks, yeah-- they aren't worth their weight in iron.

This is what a real V-Gouge tool should look like. Sigh...

fix f-spot downgrade version crash database

2009-07-27T20:18:00.000-07:00

Have you ever downgraded F-Spot from Debian Unstable to Stable, only to find that the moment you create a "version" of a photo, your entire F-Spot gallery becomes hosed?

The solution is to fix your database to not include the new fields that came with whatever that new version of F-spot was, and make it like it was back in F-Spot 0.4.4. F-Spot might even be nice and move your "broken" database to the root of your home folder. Never fear! Open up the file "photos.db" (which may be at ~/.gnome2/f-spot/) in your favorite SQL Lite editor (apt-get install sqlitebrowser). Now, modify the photos and the photos_versions table to remove the md5sum field. That's it!

They must have added md5sum because it was a good idea, but didn't consider all of us that might downgrade to a version that didn't know about this field!

Here are the errors you may see:

Starting new FSpot server

Unhandled Exception: Mono.Data.SqliteClient.SqliteExecutionException: SQL logic error or missing database
at Mono.Data.SqliteClient.SqliteCommand.ExecuteStatement (IntPtr pStmt, System.Int32& cols, System.IntPtr& pazValue, System.IntPtr& pazColName) [0x00000]
at Mono.Data.SqliteClient.SqliteCommand.ExecuteStatement (IntPtr pStmt) [0x00000]
at Mono.Data.SqliteClient.SqliteCommand.ExecuteReader (CommandBehavior behavior, Boolean want_results, System.Int32& rows_affected) [0x00000]
at Mono.Data.SqliteClient.SqliteCommand.ExecuteNonQuery () [0x00000]
at Banshee.Database.QueuedSqliteCommand.Execute () [0x00000]

Starting new FSpot server
Exception in Gtk# callback delegate
Note: Applications can use GLib.ExceptionManager.UnhandledException to handle the exception.
System.NullReferenceException: Object reference not set to an instance of an object
at FSpot.Utils.UriUtils.UriToStringEscaped (System.Uri uri) [0x00000]
at FSpot.ThumbnailGenerator.ThumbnailPath (System.Uri uri) [0x00000]
at FSpot.Widgets.IconView.DrawCell (Int32 thumbnail_num, Rectangle area) [0x00000]
at FSpot.Widgets.IconView.DrawAllCells (Rectangle area) [0x00000]
at FSpot.Widgets.IconView.OnExposeEvent (Gdk.EventExpose args) [0x00000]
at Gtk.Widget.exposeevent_cb (IntPtr widget, IntPtr evnt) [0x00000]
at GLib.ExceptionManager.RaiseUnhandledException(System.Exception e, Boolean is_terminal)
at Gtk.Widget.exposeevent_cb(IntPtr widget, IntPtr evnt)
at Gtk.Widget.exposeevent_cb(IntPtr , IntPtr )
at Gtk.Adjustment.gtk_adjustment_value_changed(IntPtr )
at Gtk.Adjustment.gtk_adjustment_value_changed(IntPtr )
at Gtk.Adjustment.ChangeValue()
at FSpot.Widgets.IconView.ScrollTo(Int32 cell_num, Boolean center)
at FSpot.Widgets.IconView.ScrollTo(Int32 cell_num)
at MainWindow.JumpTo(Int32 index)
at MainWindow.LoadPreference(System.String key)
at MainWindow.HandleIconViewReady(System.Object sender, System.EventArgs args)
at Gtk.Widget.SizeAllocatedSignalCallback(IntPtr arg0, IntPtr arg1, IntPtr gch)
at Gtk.Widget.SizeAllocatedSignalCallback(IntPtr , IntPtr , IntPtr )
at Gtk.Application.gtk_main()
at Gtk.Application.gtk_main()
at Gtk.Application.Run()
at Gnome.Program.Run()
at FSpot.Driver.Main(System.String[] args)

USAA Deposit at Home on Linux

2009-04-08T22:47:00.000-07:00

*update* Thanks to Dave for the idea,
*update* Thanks Garrett, see his comment below. We may all be wise to send USAA a suggestion via the feedback link. Just remember to be nice. The last thing we need is for USAA to decide to implement better browser detection to specifically block linux. Or worse, implement Silverlight. In the meantime:

Just set your user agent using a firefox addon to:

Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; sv-SE; rv:1.9.0.8) Gecko/2009032608 Firefox/3.0.8

If you have trouble adding that user agent, here is what I did after you install the add-on above:
Tools-->User Agent Switcher-->Options-->Options
Useragents-->Add
Description: Firefox Macitosh Intel for USAA (or whatever you want)
Useragent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; sv-SE; rv:1.9.0.8) Gecko/2009032608 Firefox/3.0.8
OK
OK

Make sure you switch to that user agent before even going to USAA.

And make sure you have the java plugin and you are good to go! Thank you macintosh for having a marketshare to help us linux fools get stuff working. The macintosh java client allows you to simply select pre-scanned checks with your choice of software. Nice!

Note: This assumes you can get your scanner to work in linux which is assuming quite a bit :-)

sleeping your computer

2009-03-29T00:40:00.000-07:00

Sounds easy, right? You go into Power Management and set it to sleep after 30 mins. Done deal. Well what if you've enable fast user switching? Now all-of-a-sudden your computer goes to sleep because your wife is idle on VT8 while you are active on VT7. Dammit!

Here is a work-around: don't use X to sleep the computer. Disable sleep for each profile, then:
apt-get install sleepd
edit /etc/default/sleepd
mine looks like:
PARAMS="-U 1800 -u 1800 -i 22 -i 23 -s \"s2ram -f\""

The default is to hibernate which is silly for a diskless desktop, so I s2ram instead. The interrupts to watch can be discovered by:

watch -n1 cat /proc/interrupts

Now wiggle the mouse and hit keys on the keyboard to discover which interrupts increment when you do that.

multiseat 3D. denied (for now)

2009-02-09T20:24:00.000-08:00

So I've been trying to figure out a way to let my daughter play the "duck game" (or at least watch the penguin drift aimlessly down the hill) while I do whatever else I am doing that is so damn important. Naturally, the first thing a normal person thinks to do is hook up another monitor, keyboard, and mouse to their existing computer. Right? Everyone does this? No.

This is basically the dream. However, to get there from here you need TWO video cards. I have an PCI-Express Nvidia card. So I needed another PCI video card that can do 3D. In case you don't know, PCI is kind-of getting obsolete for video cards these days so it isn't easy to find one. My brother kindly gave me an ATI Radeon PCI something or other. Great! Plug it all in and I'm ready to roll.

Wait. Nvidia ships with proprietary OpenGL libraries. ATI ships with proprietary OpenGL libraries. Damn! You can't mix the two! So I spend $50 on a Sparkle brand Nvidia card just like my PCI-Express version and now I have TWO identical cards except for the interface. And now here is where we come so, so close...

I get it all working. Using the config example earlier I get two logon prompts on two monitors. I can log in on one and on the other. OpenGL games work on both! Most importantly, the Duck Game works! I tried Quake3 but it is pretty darn slow, but that might be related to a serious problem: one of my three cpu cores is completely pegged while the second instance of Xorg is running. I had the same problem with the ATI card (using the free non-GL drivers), so it seems to be an Xorg thing.

Another problem is that I cannot switch consoles (seems you must disable this for dual Xorg instances to work). This means no "switch users" functionality (unless you count logging on to the other monitor). So now it is harder to share the computer with my wife, which is ironic since I doubled the seats! Finally, sleep mode doesn't work so well, coming out goes to a blank screen and seems to be crashed.

So maybe I'll post a bug report to Xorg and these issues can be resolved.. but I sort-of doubt it since there is very little demand for this multiseat business...

** Update**

Xorg version 7.4 provides GLX pass-through-- so I should be able to xephyr and not fuss with xorg instances. This might solve everything....

How to Lose Data the Microsoft Way

2009-02-09T13:11:00.000-08:00

1. Use File and Settings Transfer Wizard

I should end here, but just for posterity...

2. Uncheck all the options and only select the option to backup specific folder. Specify "C:\Documents and Settings". Chuckle to yourself as you wonder if anyone else was clever enough to use this to transfer multiple user accounts.
3. Watch the backup process succeed in creating a large .DAT file of unknown composition.
4. Assume you know what you are doing.
5. Format, Reinstall, and attempt to restore using the wizard.
6. Stare in bewilderment at all the missing user accounts and lack of data.
7. Cry a little
8. Create all the user accounts and try running the wizard on each account while logged in.
9. Allow a small gasp of hope when you notice all the avatars are restored on the Welcome Screen. It must have restored their data!
10. Cry again when you realize it didn't. At all.
11. Unpack the F.A.S.T archive using some obscure 3rd party program called fastconv.exe.
12. Cry some more after it fails on the translation database and you are left with thousands of arbitrarily named .DAT files. Try it again in WINE and get the same error.
13. Write a script to add extensions to the files based on magic library... and cry again when you realize the small number of files are only related to the user account that was logged on during the initial F.A.S.T migration.
14. Curse the heavens, curse Microsoft, then curse yourself for being such an idiot.
15. Blame the user for not making regular backups.

How to remove a Bee Swarm

2008-05-17T12:38:00.000-07:00

We have a rotating compost drum in the back yard, and twice now I've seen some bees taking a tour of it, which made me a bit nervous. Well, this morning I went outside and I saw a huge wad of bees on the thing and it looked like they were settling down for good. Rather than look on the "internet" for suggestions, I tried a technique that I can only describe as a "bright idea".

The bees were on the shady side of the drum (it being about 10AM), and since the drum is painted black, I imagined that after Noon or so the sun would probably be beating down on them and they would decide it was too damn hot. Rather than wait around, I decided to speed things up.

Being in the midst of a bathroom remodel, I had at my disposal two mirrors. I simply placed each mirror about 15 feet away and angled such that the light was blazing on the bees. One mirror might not have been enough, but with two mirrors those bees were cookin'! Within 5 minutes a huge glob of molten bees plopped onto the ground. They rose up in a cloud of fury and seem to be gone, save a few stragglers still inspecting the drum. They never even approached the mirrors, so I believe it is safe to say they don't consider the sun to be a threat (who knew bees were so dumb?).

So, if you see a blob of bees hanging out on your property, find some mirrors and make their life unpleasant. They should go away. If they attack and kill you or anyone I take no responsibility!

Time Machine over Network Share

2008-05-06T22:45:00.000-07:00

Here's what I did after reading several articles about this:

Open Terminal:

defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1

Connect to your network drive and save your password
Open Time Machine Preferences:
Select your Volume
Click Backup Now or wait for it to start.
Look on your volume and you will see a file called:
machinename_3493951911.sparsebundle or something similar
copy the first part not including sparsebundle
Wait for time machine to fail :-(
Open Disk Utility and click New Image
Paste in the name you copied and choose Desktop as the location. Change the type to sparsebundle. Give it a reasonable size and click create.

Unmount it and copy this file to your network drive. it should be about 80MB. Now go back to time machine preferences and reselect your network share. Click backup now and you are good to go!

Pie Charts Lie

2008-02-27T22:35:00.002-08:00

Do these two charts appear to even remotely depict the same information? Supposedly they do. Is it just some sort of optical illusion?

"Almost there, buddy!"

"You might as well switch majors."

Apple's Bootcamp bungles GPT specification

2008-01-17T18:51:00.000-08:00

Ever wonder how Bootcamp works? Well, Apple has basically messed up the GUID partitioning standard to make it work with Windows, even though they could have just stuck with MBR and kept things simple. It is a horrible, horrible kludge. We finally figured out what this guy already found; partitioning and imaging a Macintosh is a real bastard, but possible. And no, Bombich's software (although pretty cool), just doesn't cut it when you already have a PC solution (Altiris Deployment) and a Mac solution (Xserve+NetInstall).

The GUID specification calls for a "protective MBR" with exactly ONE partition (with an ID of 0xEE). No matter how many partitions you create in the GUID table, there should only be ONE partition in the MBR table. ONE!

What Apple has done is make a hybrid GPT/MBR. In this case, "hybrid" is synonymous with "bastardized". Any partition you create (with apple tools) in the GUID table gets copied to the MBR table. This is why when you install bootcamp, you CANNOT remove the partition and recreate it; the geometry would not match what is in the GUID table. Once the two tables are out of sync, it's a real bastard to fix. ReFIT has a program called gptsync that will sync one way; GTP to MBR... but there is no reversal of that.

The really funny part is Apple's Tech Note from 2006 (probably just before BootCamp). They describe the Protective MBR as "a single partition entry (of type 0xEE) that covers the entire area of the disk used by GPT structures and partitions." A single parition? A Bootcamp Mac has three!

Furthermore, Apple mentions "Specifically, if block 0 contains an MBR with more than one partition entry, or a single partition entry whose OSType is not 0xEE, it is not a compliant GPT disk, and manipulating the GPT may cause dangerous inconsistencies between it and the legacy MBR."

and they follow that with a:

WARNING: Failure to comply with this recommendation may result in the loss of user data.

So there you have it... Apple's GPT support is completely laughable and confusing as hell. They completely violate their own recommendations not to mention the specs.

Ironically, I can use Apple's DiskUtility to format a Leopard Mac with good old MBR and 2 partitions. I can restore a Windows XP image (via RapiDeploy) and a Mac image (via netinstall) to these partitions, and THEY ARE BOTH BOOTABLE just FINE. The caveat is, you can only boot from EFI (holding the option key). Once you're in Mac OS or Windows, NONE of your disks appear in the startup disk preference pane (you can't even select the disk you are booted to). It's kinda sad when EFI is smarter than your proper OS...

Don't get me wrong; EFI and GPT are totally awesome technologies-- I just hope we can stick to the standards. This means Microsoft: Get on the ball and support EFI and GPT for Windows XP and Vista. And to Apple: Why don't you stick with MBR for dual-boot Macs? You only support 2 usable partitions anyway!

Another Marpac Sleepmate/Soundscreen 980A Review

2007-12-21T19:54:00.000-08:00

There is already a really good review of this sound machine over here, except they didn't really tear the thing apart.

Inside: At the heart of the Marpac 980A is a high-efficiency Jakel J238-038-3325 C Frame Motor. Ok, it's just a fan.

That's really all there is to it. If it ever breaks, you can find replacement motors online. These are the same motors used in bathroom exhaust fans. You can find motors like these for under $10 at surplus sites online. So, if you're really cheap you can spend a lot less than $50 and build your own. Of course, it will be ugly and probably cause a fire. . .

The Marpac Sleepmate/Soundscreen 980A is rated "less than 40 watts". I was concerned that this sound machine might use more power than our iBook (which previously served as our sound machine via the nifty Noise utility), so I decided to test the Marpac with a KillaWatt.

I was surprised that at low speed the unit only draws 6 watts.

On high, 13 watts. This is considerably less than the .33 amps (39 watts) that the motor is rated for. I'm not really sure why this is the case; perhaps because the motor is hardly under any load, having been fitted with such small fan blades? In any case, it'll cost less than $10/year to run 8hrs/day. Probably closer to $2.

Ok, finally, here's a video of the unit in action, at BOTH speeds!

Overall, we're very happy with the noise that the machine produces. Although it is a lot different than the Noise application, I think it is more soothing and has a much larger range of sound, probably due to the fact that the speakers in an iBook can't create any bass to speak of. I am also very sensitive to "sound loops" produced by some electronic noise machines, and of course this machine is completely immune to that. Overall it is a simple, low-tech solution to an old problem, and more elegant than a box fan.

Create a Slick Black iMac In The Gimp

2007-12-07T08:28:00.000-08:00

Yeah, sure, you can follow this long and tedious PhotoShop tutorial over here and make yourself a nice black iMac in about thirty minutes. Or you can spend about a minute and thirty seconds and do "virtually" the same thing in The Gimp, a Free OpenSource Image Editor.

Step 1

Grab an iMac image and save it somewhere.

Step 2

Load it into The Gimp, and inverse the colors: Filters-->Colors-->Value Invert. We're almost done already!

Step 3

Now all you do is UN-invert a few things, and you're done! Now seriously, why would you want to waste all that time in Photoshop, when you can do the same thing a hundred times faster in The Gimp!? That's the power of OpenSource! YeeeeeAwwwwwww!!