steven n fettig's Jitterin' Thoughts

Start with SuSe an install CD downloaded from one of the SuSe mirrors. (I still haven't tried nor figured out how to download the complete collection - which is helpful timing-wise when installing the system afresh.)
Boot install CD.
Activate kernel module for the Intel PRO/100 network interface.
Install via FTP using the beginning instructions from Tutorial: How to install SuSE 9.0 via ftp. Essentially, the trick is making sure to use a viable mirror for the sys-install. In the case of the howto I am referencing, the writer uses:

[BAWUG] dBM and dBi
Tim Pozar pozar@lns.com
Thu Mar 7 15:39:00 2002

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On Thu, Mar 07, 2002 at 06:06:59PM -0500, Stefan Schueller wrote:
> How do I convert dBM to dBi or watt and what is the legal limit? 36dBi or
> dBM?

Both answers can be found from my paper "Demystifying the FCC's
Part 15 Rules and Regulations on ISM power limits" at:

http://www.lns.com/papers/part15/

--
At the end of the paper...
--

1.deciBels - dB

dB, or one tenth of a Bel, is a unit of mesurment that looks
at the ratio of one value to another. Gain or loss can be
measured in dB. The dB scale is an exponential scale using
the formula log(ratio)*10. This means that 3 dB is about
twice the power, 10 dB is 10 times the power, 13 dB is about
20 times the power and 20 dB is 100 times the power.

2.dBm

dBm is deciBels referenced to a value of 1 miliWatt of
power. Power over or under 1mW would be plus or minus dBm
respectively. If you have a transmitter that produces 1
watt of power that would be 1000 times more than 1 mW so
that converts to 30 dBm.

3.dBW

dBW is deciBels referenced to a value of 1 Watt of power.
Power over or under 1 Watt would be plus or minus dBW
respectively.

4.Effective Isotropic Radiated Power - EIRP

Effective Isotropic Radiated Power defines the gain of an
antenna over an "isotropic antenna" that would radiate
equally in all directions.

If you have an antenna that radiates better in one direction
than another, it would have gain in this direction. The
amount of gain would be shown as "dBi" or dB gain (or loss)
over an "isotropic antenna".

--
Snail: Tim Pozar / LNS / 1978 45th Ave / San Francisco CA 94116 / USA
POTS: +1 415 665 3790 Radio: KC6GNJ / KAE6247
"It's a damn poor mind that can only think of one way to spell a word."
- Andrew Jackson
"What is wanted is not the will to believe, but the will to find out,
which is the exact opposite." - Bertrand Russell, "Skeptical_Essays"

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...I do this all the time. I modify my pf.conf file for Anywhere Technology's main router/firewall, but I always screw something up because I forget the following:

order for pf goes in: options, normalization, queueing, translation, filtering

So, many of you may find this post useless, but it may help me finally remember it without going through the frustration of ...syntax error on line xyz.

Oh, and this diagram kicks ass, too:
http://homepage.mac.com/quension/pf/flow.png

A few days ago, I finally updated the qmail howto that I had been maintaining for a few years to notify people that they are better off going to lifewithqmail.org for more accurate information on how to install and/or maintain qmail. I have not done the job of a howto writer in keeping the document accurate or up-to-date. A recent post on the OpenBSD misc mailing list made me think more philosophically about providing howto's and their inherent problems. Software developers work hard to document their programs. Their documents are designed to guide you through the installation and configuration of the software. A howto allows you to skip all of this in the hopes of providing you an "easy out." That's what it comes down to - you are trying to get at the easy way out of learning a piece of software in order to install it as quickly as possible - and this has major caveats. While trudging my way through learning how to install and configure postfix (and the kitchen sink), I found a great number of howto's that were either out of date or inaccurate. It was unnerving the amount of bad information was available on configuring amavis-new in particular. If I had simply gone to the information provided in the software readme's and install guides, I would have found up-to-date information that I was looking for. If the software's documentation was poor, the worst thing I could do is go to the howto to see how to get it to work. Why? Because if the software programmer can't maintain or get accurate documentation written, how well do you expect the software to work? I'm not trying to slam the hard working software developer who struggled to finish a project but had a hard time writing documents (how many writers are good programmers and how many programmers are good writers?), but personally, if your documentation doesn't explain how things work so that I can install them properly, then how do I expect to maintain it such that my server doesn't get bombed with a bug or some other sort of problem.
There is a difference between a guide and a howto. The name howto implies that you will need everything to get started. Perhaps. You are missing one very important element: knowledge and understanding of how things work and why they work the way they do. I learned a very important lesson last year when I inadvertently updated perl on my email system and completely destroyed the SpamAssassin installation. For hours, my server was throwing mail around queues and didn't know which way to take things. I, because I had never taken the time to understand what the hell I was doing, almost had a heart-attack as customers started calling to complain because they couldn't receive email. I vowed after that to never install something without at least a precursory knowledge of the software I'm implementing and how it works. Yesterday I spent the better part of 8 hrs. trying to figure out why amavis-new and SpamAssassin weren't tagging obvious spam. It was because of one line @local_domains_acl = ( ".$mydomain" ); that was missing in every freaking howto that purported to explain how to install postfix and the kitchen sink (well, except one). I figured this out by shutting down the caffein flow to my veins and taking a long, hard look at the amavis-new documentation - and there it was... right in front of my eyes.
So, the next time you decide to use a howto to configure something to be used in production, be under advisement that you do so not only at your risk but the risk of all those you are supporting.*

*This doesn't mean I'm going to stop providing "notes" on this website, but please be forewarned - none of those are meant to provide a howto anymore <wink>.

While its late - so late that I should have been asleep a few hours ago, I have been toying with so many things over the past few weeks that I had to finally do some fly-by note taking:
Q: this is the latest QEMU emulator available for OS X (at Q [kju:]) and it rocks. I bought a new MacBook Pro - I couldn't wait for rev2 because I was dying to see how Intel performed (notes below) and the performance of OpenBSD under Q on OS X is fantastic. The only thing I still can't figure out is networking and why I can't get packets past the emulator, but I'll have to do more digging on that one later. As far as performance of moving around the system, adding packages, etc. is concerned, it is very impressive. Considering my thoughts under the PowerBook (even the 1.67GHz model) was less than appealing, I am happy (and the fact the VirtualPC won't work on the new Intel machines - and I'm not sure given my recent bout of problems with that application that I will invest in it again).
MacBook Pro: I love it. Period. People are complaining about different items missing from the hardware like the S-Video connection and modem. I could care less (modem... well, I do a bit, but not too much). The machine is stellar. I like the built-in iSight (yes, I actually use it) and the speed. No, not the speed with regards to non-universal apps - especially Microsoft Office and Adobe products. Yuck. The performance is no better than my PowerBook. Where I notice the difference is on Intel native (i.e. universal) applications and especially on unix related stuff that I compile. I honestly think the performance on compiling ports (vis a vis darwinports.org) is better than on my dual 2.0 G5. I haven't actually timed anything - yet - but it has thoroughly amazed me. I'm happy all around and hope to do more writing on the topic later.
AFPoverTCP: i.e. Apple native file sharing on an 802.11g network. Quick quips: Stream DVD's? Not unless you really monkey with buffer settings in VLC (set file buffering to 10,000 ms). At least it is not consistent. I really don't know what Apple is going to do to make streaming video over 802.11g any good. Unless they tweak all of their media programs to do better buffering, people will be sorely disappointed if they think they are going to network a small army of Mac Minis together to create a hodge-podge video and content streaming network. The throughput is so inconsistent (even if I'm sitting 2 ft. from the AP) that DVD's often drop out and/or become choppy. I finally tweaked VLC enough to get it working to my satisfaction, but that is not for Joe-Mac-User. I really can't figure out how Apple has let afp performance slide so horribly. Even when looking at file transfer performance on a gigabit network, the best I see is 367mbps on file transfers (yes, single large files). That is some overhead... ridiculous. I'm going to look more into seeing if there are system related tweaks one can make to get better performance out of the built-in networking devices, but who knows. With the theoretical speeds of today's networks, a lot of what we want to do should be possible - i.e. stream high(er) definition video content from machine to machine. Unfortunately, instead of focusing on making things better, we're stuck with developers and companies trying to add some new, unneeded button to already good hardware. 17mbps of real throughput on [advertised as] 54mbps network gear is ridiculous. That equates to around 2mBps - just around what a DVD showing full color frames will stream at. I love living on the edge...

I have tried and tried and tried and finally succeeded (after succeeding once only to squash it because I wanted to do more). To properly set up a SIP connection to your Gizmo account so you can use Gizmo for outbound calls, you need to have the following info set:

General Settings
Outbound Caller ID: 1747XXXXXXX (your Gizmo SIP number if you wish)
Maximum Chanels: 1 (I haven't tested higher numbers)
Outgoing Dialing Rules (I didn't make any changes or fill any of the fields)
Dial Rules: blank
Dial rules wizards: default (pick one)
Outbound Dial Prefix: blank
Outgoing Settings
Trunk Name: gizmo (set this to what you want the trunk to be called)
PEER Details:
allow=ulaw&alaw&ilbc
context=from-pstn
disallow=all
dtmfmode=rfc2833
fromdomain=proxy01.sipphone.com
fromuser=1747XXXXXXX
host=proxy01.sipphone.com
insecure=very
secret=your_password
type=friend
username=1747XXXXXXX

(for username and from user, replace with your Gizmo SIP number)

Incoming Settings (I've left all blank for now) - UPDATE - see below, not needed
Registration
Register String: 1747XXXXXXX:your_password@proxy01.sipphone.com

I then set up a dialing rule that requires you to dial 8 to get your Gizmo "line" and it works. So many of the instructions I found were half baked, didn't work, etc. You must especially have fromdomain and fromuser set for outbound calls to work. Sometimes the internet is filled with a lot of crap...

Later, I'm going to try to figure out how to set up incoming calls.
UPDATE: Wow... Inbound works fine as long as you have your routing properly set up - i.e. leave the above settings alone. If you are having problems, it is likely that your router is blocking certain incoming ports.
Continuing Notes (21 March 2006):
While I don't completely recommend it, you can put your Asterisk server as your/in your DMZ (if you have a single IP or are on the type of connection where you have no control over your IP, then that means you are probably using a SoHo router - e.g. Linksys, Netgear, D-Link, SMC, etc. - and you can place your machine "outside" your firewall to make sure the proper ports are open to you Asterisk server). Once you've figured out it works inside the DMZ or on a static IP with no firewalling, then you can slowly close down ports. The better way to approach this would really be to open up ports slowly, but this can be time consuming because for some reason, it can sometimes take some time for your incoming calls to be routed properly.
If you understand the following jargon, then the following port openings will work fine (if you're behind NAT, this means you need to port-forward the following ports to your Asterisk server):
TCP: 5060
UDP: 69, 5004, 5060, 5061, 5062, 5063, 4569, 5036, 8000, 9999-20001, 2727
The ones I bolded seem to have been part of the key for my setup - but, I'm doing quite a bit more than running my Gizmo inbound and outbound calls through this box.
Because my Asterisk server runs on a static IP, I simply had to open up my main firewall ports to that box.

One for the archives:
As of OS X 10.4.6 the unix command dump still doesn't work. This is nothing more than pure bullshit. dump is arguably one of the most important utilities known to unix. Why doesn't it work? Because it doesn't understand HFS/HFS+. Why it is still part of the system is beyond me. Take crap out that doesn't work on your native file system. Wonderful... it will work if you have everything formatted UFS, but who cares since running a sys off a disk formatted in UFS creates a load of other problems. Shame on Apple - they don't deserve to make the following claim, "Command-line Environment UNIX users will feel at home in Darwin, the robust BSD environment that underlies Mac OS X..." (apple.com/macosx/features/unix/) This is so damn simple... yet still not fixed six years later...

Key Words: OS X, Mac, dump, cannot, can't, work, Apple, doesn't, broken, does not, can not, sucks

(Why am I making such a big deal? When you rely on dump to do backups in a mixed unix environment, you would think that your most expensive and valuable unix system, OS X, would have a functioning version of a unix tool recommended by most people who are serious about backing up their systems. After days of not understanding why I couldn't get it to work, I finally found mention of why on some website. And, frankly, I don't get it.)

After thinking the game was over when I got Amanda to install and run on my Xserve, I came to the brutal realization that I was way off. Once again Apple has changed the way things start up (or may start up, or may be configured to start up...) in OS X and has moved to launchd - this specifically hits those of us used to crontab. Great... yet another scheduler to learn. Anyway, in order to get OS X (10.4.6 as of this writing) to check disks and then run amdump, I spent the whole morning building the following plist files:

(This one runs amcheck and always mails the results to me - net.amanda.amcheck.plist)
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Label</key>
<string>net.amanda.amcheck</string>
<key>ProgramArguments</key>
<array>
<string>/usr/local/sbin/amcheck</string>
<string>-a</string>
<string>anywheretechnology</string>
</array>
<key>ServiceDescription</key>
<string>run amcheck to make sure that dumps are properly made</string>
<key>StartCalendarInterval</key>
<dict>
<key>Hour</key>
<integer>13</integer>
<key>Minute</key>
<integer>22</integer>
</dict>
<key>UserName</key>
<string>amanda</string>
</dict>
</plist>

After reading some more at afp548.com, I'm not sure I have the ProgramArguments set up correctly in that it may be more correct to have a Program key above it, but this works and I've verified that a dozen times. The only question is whether or not it will work every day...

(this is the script that actually runs amdump every night at 2 am - net.amanda.amdump.plist)
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Label</key>
<string>net.amanda.amdump</string>
<key>ProgramArguments</key>
<array>
<string>/usr/local/sbin/amdump</string>
<string>anywheretechnology</string>
</array>
<key>ServiceDescription</key>
<string>run amdump every day at 2 am</string>
<key>StartCalendarInterval</key>
<dict>
<key>Hour</key>
<integer>2</integer>
</dict>
<key>UserName</key>
<string>amanda</string>
</dict>
</plist>

So there you have it. Amanda runs happily - still not backing up OS X machines, but at least the others so I can finally put some of that 5TB to use.

OpenSSH is the reason I started to use BSD *nix - particularly FreeBSD (and now OpenBSD) - back in the days of my first experimentation with qmail. But, I never knew that using ssh with the -D switch allowed you to use the port forwarding mechanism as a SOCKS proxy... This is an example of link stumbling: I was on the road at the end of last week and I'm forcing myself to be more secure about my surfing habits and transmit most anything I do (i.e. email and web browsing) through my own servers. In order to do this, I had to set up a minimum of four tunnels for the traffic, one to my squid server, one to my smtp server and two to the two different mail servers I access. So, I remember seeing a program for OS X for which you could set up profiles to automatically start up x number of ssh tunnels (because I'm too lazy to write the script to do so myself) and I googled "os x set up ssh tunnels" and happened across Marc's Combining ipfw/natd and SSH Tunnels which then pointed me to SSH as a SOCKS Proxy. Sometimes it is truly amazing what one can stumble across. I was so excited to write about this (kind of a note to myself), that I still haven't found the program for which I started looking in the first place. OpenSSH really does rock... and by the way, next time read the friggin' man page! (note to self)

With the redesign (thanks Aaron) of my "start" page, I wanted to slowly move changes into the different weblogs I write. Those changes include:
• Coming up with a unified search for any and all of the sites. (Done through the use of Google's customized search tools - not yet added to the sidebar, though.)

• Coming up with a unified rss feed for any and all sites. (I have some leads, but I'm not even close to understanding how rss is actually produced by MovableType and WordPress.)
• Coming up with a new color scheme for stevenfettig.com/mythoughts/. (This is getting really old.)
• Coming up with some way of dealing with comment spam. I've been desperately avoiding this issue for a long time now and simply need to find a way to deal with it. I miss the comments I received for some of the howto postings I've put up over the years. The comments have not only been helpful, but have led me to meet new people. Comment spam is such a waste of time and right now, I receive well over 200 a day on the two weblogs that have been around the longest (stevenfettig.com/mythoughts/ and rescogitans.net/blog/). So, what I've decided to do is remove mt-comments.cgi all together. Once I have learned a way to deal with the crap, I'll put it back in service and hopefully reconvene commenting.
One of the reasons I still even pursue weblogs is that, 1) I'm an avid reader of around 10 and skim through over 60 different ones in a a week's period of time and 2) I like the outlet. We have had a number of things occur at work and with a business venture I ended and whose remains I used to start a new one. Both of those activities have produced a lot of experience and a lot of thought on various topics. In a way, I really do this all for myself. For the two people out there who actually look at any of my writing regularly (thanks dadLaw and naked guy in a lawn chair who is really freaking me out), I really do appreciate the readership and someday, I'll maybe be consistent enough to generate content on a regular basis. So, I want to keep doing it and while putting some energy into it, I'd like to make the experience "nice" for the readers out there.
Step one was the new entry page. Step two... well, that's a conglomeration of things.

When Apple introduced their new AirPort Extreme and I started digging around at the specs, I got quite excited: it could act as a mini file server. I was less excited about the speed specifications of the 802.11n draft because the fact is that it still doesn't come close to performing like gigabit ethernet, and because I'm usually pushing around video content in the gigabytes range, I rely on wires. (Plus, I know that reality never coincides with the test environments where wireless specifications are proven. And, I have so much wireless equipment littering the airwaves in my house that I expect diminished performance in whatever I have bought.)
But, as a mini file server vis a vis a USB Hard Drive, I thought, "wow, my prayers are answered. Apple usually does things the easy way and this has got to be one of those products."
I have seen a number of published reports from MacWorld, MacNN and a few other tech weblogs that have either dissected the device and/or tested primarily wireless performance. Wireless speeds are all across the board. MacWorld has a review that best explains why you will see better speeds using the 5GHz settings instead of 2.4GHz:

When a network was using 2.4GHz channels (or ranges of frequencies) shared by other nearby networks—as many as five networks showed up in testing on one channel—we still saw typical speeds of 50 Mbps. On unused channels, a rarity in cities, we saw rates of 70 to 80 Mbps. (via Macworld Review: AirPort Extreme Base Station)

The fact is that with all of the devices out there that can potentially interfere with products like the AEBS, people should be happy to see performance of half of what it is advertised to do - especially if they are not knowledgeable of what equipment may or may not interfere with the device.
My own opinion has very little to do with the wireless side of the equation (other than, I have my base station set at 802.11n 5GHz only - and it works great that way, except range is very limited in my house), I am more interested in performance as a file server. Simply put: it sucks. If you want to backup, store or share small files - or even tens of thousands of small files - the performance is certainly not that of a file server (or a bastardized Mac being used as a file server), but it is adequate. If you want to serve huge media files, forget it.
I should have known, though. My experience with using small, low power devices as file servers has been telling. An old P5 100MHz was one of the first machines I tried to use as a power file server. It was the first big tower computer I purchased with my own money when I went to college and had done its job for years, but about two years ago, after collecting dust for a year in our basement, I decided to throw OpenBSD on it and set it up as a file server. It performed, but not well. There simply wasn't enough horsepower from the processor or the motherboard to push a lot of large files (large being multi-gigabyte) through my home network. It sufficed for storage, but not a lot of reads and writes from multiple devices. My next attempt was to use a Soekris board an HD connector. Same exact problem: not enough horsepower. So, I ended up biting the bullet and taking a PowerMac G5 that sat idle most of the time and turned it into a file serving power house (to make up for going overboard on the processor of said file server, I used a lot of its idle time to transcode video). With that in place, I was able to transfer 10GB DV files and transcode to my heart's content.
What I had hoped for in the AEBS was something low power to simply copy content to and server content from. I realized that with a 10/100 ethernet connection that transfer speed expectations shouldn't be overly enthusiastic, but they should suffice.
Well, transfer speeds are sufficient. The problem is that the AEBS locks up all the time when transferring large files to and from the attached storage. To simplify my testing, I removed the three 500GB drives from the USB hub and attached one, 500GB LaCie USB drive. I decided that whatever content was to be moved to the drive ought to be moved to it from a wired device. On five different occasions - and the only five I tested with the single drive - the AEBS locked up and I had to unplug it to get it working again. I tested by sending 20GB of 1-2GB video files to the drive. I didn't ever get to the process of reading from the drive... Half of the time, the base station itself would still act as an access point, but clients could no longer access the shared drive.
Sorry, but that just doesn't cut it. I have some thoughts on why this is happening (i.e. memory buffers on the AEBS are filling up, etc.), but Apple should know better. They should know that because their market is somewhat driven by video and music content, they should expect people like me wanting to use the AEBS as a mini file server for said content. If I can't copy large files to it, how shall I ever read from it?
None of what I have written has been proven through scientific method and may be a result of a problem with my specific AEBS (which is why I ordered another one), but it is somewhat telling: don't expect much, if anything out of this file server's capabilities. Hopefully these are issues Apple will fix. This is yet another reason why I hate rev0 Apple products...

Technorati Tags: airport, apple, hardware, wireless

Sorry - I have a css mess on my hands ;) I'll be back asap...

Update 24 March 2007: Well, the beginnings are done. I'm still working on better navigation and a background image for the header, but I like the plain, clean look. Comment if you don't (now having integrated all three blogs, commenting should finally work and be under a bit of control) or if you have any advice. (By the way, IMing me would be easier.)

I ordered an Apple TV when Apple announced that they were for sale and finally received my first batch this week. For the past two years, I've been using Mac Mini's as a type of custom home theater PC to access content I store on a central server. While this works quite well for me, guests and my wife find the process of getting to the content overly complicated (and I find the same thing when problems arise). So, it appears that the Apple TV will fit in well and bridge the gap between what we are already using and what we are missing.
I started transcoding a bunch of HD programs I had recorded into h.264 files. I set the resolution at 1280x720 and tried different bit-rates. I ended up finding that 2500 kbps and above worked pretty well. While 1500 kbps worked, it lacked the color composition that seemed to come out of a higher bit-rate. In reading the Apple TV documentation, I found that the Apple TV is capable of reading 1280x720 h.264 content at 24 fps. Now I'm wondering if that last piece means that I had to transcode at 24 fps or that it was simply capable of reading 24 fps regardless of the encoded framerate. Tonight I was able to finally test a number of recordings and was thoroughly disappointed. At 24 fps, the picture is choppy, especially if the scene has any movement or detail with movement. My tests in transcoding are far from scientific and I realize that I may have made a mistake in other settings choices, but I see the same issue when playing the content back on the Mac Minis, PowerMacs or MacBooks. In those cases, though, I usually don't bother in transcoding because they are capable of handling the raw HD content.
So, tonight, I am re-transcoding a bunch of episodes of CSI to compare to what I saw this evening. This time, I'm leaving the frame-rate at automatic and am going to see if the Apple TV can at least read the file. Even on a PowerMac (dual G5), transcoding to h.264 is very slow going - about 3 hrs per 1 hr of HD content, without multi-pass enabled (which further degrades the quality of the output video - usually I use multi-pass). We'll see... For now, though, I do not recommend the 24 fps setting on EyeTV 2, it is unlikely you will be satisfied with the picture.

Technorati Tags: apple, apple tv, transcoding, video

I guess I'll update this as I go along, instead of posting a single long essay once I have things figured out to my satisfaction. So, last night I wrote about the fact that transcoding HD content with EyeTV 2 to h.264 at 24fps left much to be desired. (Later today, I'll provide specific screen shots of what I was doing, what I did and what I'll try.) I started transcoding another CSI episode, this time no specific fps, rather, I left the settings at automatic (which means ~30 fps). I set the bit-rate at 3500 kbps (usually, more than adequate to get the color and picture content), but didn't transcode using multi-pass. Well, this morning, I fired up the Apple TV and played the clip and... it still sucks. The choppy frame-rate is gone. So, that means that the device is capable of handling over 24 fps encoded material. The picture, however, exhibited jagged edges around all of the characters on screen. The more movement, the more jagged the edges got. I remember this being an issue when I first was testing without Apple TV, but in this case, I wanted to make sure that it could handle a 24 fps+ encoded file. It obviously does. So, back to the workshop. I'm taking the same clip now and transcoding with the same settings, but this time with multi-pass set. We'll see what happens later...

Technorati Tags: apple, apple tv, technology, transcoding, video

I happened across this device on some tech related weblog (whose name and url I can't remember) and had to give my opinion. I've been using WiebeTech usb/firewire "raw" drive connectors for a few years, but the solution was always a little cumbersome; unless using it in situations where portability is key. Most of the time, I'm not in one of those situations and I have popped a drive out of a machine whose power supply has gone (or some other relatively minor problem has occurred). Now that most of the machines I deal with are SATA, I was looking for a device that made quick, raw hard drive backups (or reads) easy, yet don't clutter my desk like the WiebeTech solutions do. Like I said, I happened across mention of this device and ordered two. The shipping is ridiculous; $50 because it is being shipped from Japan, but I because the cradle is $50, I figured $75 for each cradle wasn't half bad, as long as they worked as promised. (I've found that some caddies/adapters do not perform even close to USB 2.0 specs. One transfered data from a good drive at about 4mbps. Definitely not 480mbps or close to the expected rates of around 350mbps.)
Today is the umpteenth time I've used the cradle, but the first time for an "emergency." I arrived at work this morning with my Mac Pro turned off (I leave it on 24/7 because I access it remotely quite often). I figured the power went out last evening and I went to restart it. Nothing. I fiddled with the power button, unplugged the machine, plugged it into a different electrical outlet, used a different power cord, and ran through a few procedures you use for getting Mac Pros to start if it is a simple memory board problem. Nada. I do regular backups of my two main machines now (a MacBook Pro and the Mac Pro), so I wasn't all that worried... except I had written two letters last night that I needed for work today. I spent quite a bit of time composing them, so I didn't want to go through the trouble all over. After AppleCare Phone support provided more aggravation than help (buy the AppleCare plan and find out you still have to hand deliver a Mac Pro for service and deal with an agent who obviously hasn't listened to any of the attempts I made before calling to revive the machine), I popped open the case, pulled the main drive and plopped it in the cradle. I navigated to my home directory and mounted my FileVault image ('hdid ./.snfettig.sparseimage'; enter password; access files through finder...) and grabbed the two files I needed. Done.
I can say that from the numerous backups I've pulled off drives with this cradle, I'm extremely happy with the performance and size. The fact that it will accept both 3.5" and 2.5" drives makes it all the more convenient. If you're a tech who uses drive caddies for any reason - and find that you have a lot of SATA drives you connect to - I highly recommend the cradle. Despite the relatively high price, the cradle is solid and makes life oh' so easy on days like today.

I continually forget how to do this (because I usually set it up once and never again), so I'm making a quick note of how to show the shortened hostname, username and current directory at the prompt under ksh (the default shell for OpenBSD). In the standard .profile file, enter:

HOST=`hostname`
export PS1='${USER}@${HOST%%.*} ${PWD##*/} $ '

There are ways to add color, etc. to this, but I like the plain, vanilla look it produces. Finally, I won't be likely to run commands on a machine where I shouldn't be.