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2004/02/25 SCSI/tape backup woes
π 2004-02-25 18:13 by Merlin in Linux

Current Music: none while my disk array is being rebooted every 5mn :)
Current Mood: Hardware, you will submit :)

So, I can't believe that after two years of having that tape autoloader I finally got the thing to work. It took more sweat and tears than I care to write about, but basically, in the end, one of the two busses on one of the 4 SCSI cards in that machine was flaky (some of the cables were too though).
I can't believe that I ended up fixing the problem by putting no less than 6 SCSI busses in that machine (I had to add yet another card). That just feels wrong...
Anyway, it works now and it's happily backing up data. With a little luck, the backup will be over in a week's time.

Cool, now I only need to fix my Replay TV with its broken hard drive and my older archos jukebox player so that I can ebay it. So much to do, so little time :)
I sometimes wonder how "normal" people manage :) (but seriously, it must suck to have to throw those things away, or pay god knows how much to get them fixed by someone else)
2004/02/23 Car trouble ended up ok / another mustang GT kill :)
π 2004-02-23 23:03 by Merlin in Cars

Current Music: DJ Nyman - Trance Mix (seeing a pattern yet? :)
Current Mood: Much much relieved

So, my car died today, but not just mine: the friend I was meeting for lunch never made it to the restaurant because of car trouble, and the coworker I first Emailed to see if she could get me home after boot camp never made it to work because her car broke down too this morning.
What are the odds?
(this is after a coolant leak which happened to me just two weeks ago, but I was thankfully able to diagnose and fix by myself, and I can't complain, my car has been very reliable considering that it's boosted and how I drive it ;-) )

Anyway, I was very worried because of an explosion like sound I had heard soon before the 5th time the car died on the way back from the restaurant (after looking like it was never going to start and get off the parking lot)

I abandoned the car and had a coworker pick me up and drive me back to work. I then Emailed the list from my car club (lots of gearheads, like me with computers, except with cars :) ) and I got a few possible diagnosis, including a lose crank wheel messing with the crank position sensor reading, and the different kinds of fuel delivery problems which could explain the engine not running.

My friend Matt from the list came to pick me up after work, and luckily, it was a meeting day, so I had my laptop with the Tec-II software for my custom replacement ECU (engine computer).
It only took 2mn after plugging my laptop in the serial port to realize that the ECU wasn't seeing the engine RPMs during cranking, which meant it had no idea the engine was even turning, so it didn't deliver any gasoline or spark (which makes it somewhat harder for an engine to run)
In a nutshell, my Tec-II has a very sofisticated sensor that counts the rotations in a gear and is able to tell exactly which position each cylinder is in order to provide a perfectly timed ignition along with the right amount of fuel under the boost of my aftermarket turbo

It's kind of interesting that the car didn't just die and that I was able to restart it several times as it was failing, but at the same time, it explains why I had the explosion sound that came from my engine soon before the last time it died: the sensor was failing, so the Tec-II was confused about the engine position and provided ignition at a very bad time.
Luckily it only lasted one second before the engine died, so hopefully there will be no permanent damage from that.

Just because Matt is not only a great guy, but also has everything, it turned out he had a Tec-III himself, and pulled the sensor from his car and put it in mine (luckily, his Tec-III isn't running his car yet, so he was able to do without until I buy him a new one from electromotive)
After the replacement, it magically worked much better, so we put a few zip ties, and I drove with him back to his place, as a shakedown test.

On the way there, it just happened that I pulled next to him at a light, just to play with him a bit, and didn't notice the mustang GT who was in the 3rd lane on my right.
I barely reved my engine to mess with Matt a bit, and when the light turned green, I did a decent but not complete peel out start (there was no point burning rubber, poor Matt is still boost-less for now, although you can't always tell when he goes around a corner ;)
That's only then that I saw the mustang on the other side that was trying to race me. Unfortunately for him, with my 7200 revs to redline and boost, he didn't make it and I stayed in front of him up to 3rd gear (I then stopped since we were getting very close to El Camino ;)
He must have been pissed to be eaten by my small car :-)

I've now learned something new about my car, and I'm very relieved that my engine is ok (at least it seemed to drive fine under boost during my tests).
Total cost:
  • a new boost sensor: $30-$40
  • not having to tow the car: (free since I have AAA)
  • not having some puzzled mechanic trying to understand how my car works since it's not stock in any way: saved hundreds of dollars and days without my car
  • A lap dance for Matt: $20? (not sure what the going rate is :) )
  • A car club with great and clued buddies: priceless
2004/02/22 Weekend at Kirkwood vs WRC
π 2004-02-22 23:40 by Merlin in Snow

Current Music: Dj Doboy Trancequility (silly name, but good DJ) / DJ Mike Rothwell (8H while boarding)
Current Mood: tired, but with a big grin on my face :)
Link Of The Day: Ever heard of Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch ?

This was definitely a great weekend. I was just mentally tired yesterday, so my reflexes and wits weren't quite there, which is not a good thing when you try to do a jump turn off a corniche, or ride a dense forest :)
Today was however much better (not counting the snow, which while it wasn't so much powder that you could drown in it, it was still a respectable amount).
You can find the pictures here :


Saturday was still nice because I managed to go farther out of bounds that I ever managed to go off palisades (ended up way out there on the road, past the resort)
Sunday, I used the time on the lift to study and practise a few blisnosys patterns and managed to do hard riding without stopping (eating on the lift)
Also, I used the time in the car and hotel room to finish my new anti spamc code, which I'm hoping to release very soon now, and possibly even install at $COMPANY. Those ski weekends end up being great for catching up on my personal Email backlog and coding ;)

I realized today that I'm hooked on the adrenaline of dropping from cornices, riding somewhat dense forests, and doing random jumps as the terrain allows.
I've recently become a fan of WRC (world rally championship) as I've grown the utmost respect for the folks who drive those cars balls out with a cliff on the side and half the time, without a guardrail.
Those folks drive their cars sideways at the limit of control, through snow, dirt, and even rivers, and it takes an incredible amount of split second thinking and reactions to make it to the finish line without ending up upsidedown, or in a tree. Check this highlight video out to see what I mean (warning 150MB, but it's worth it). The hardest part is in Corsica, France , hopefully there won't be any major accidents there this year.

Turns out that I've found the snowboarding I do brings similar challenges and joys when you make it (without me needing a full mechanic crew and a new car every 50km :-) ). Of course, I wouldn't dream to compare my skill to theirs, but I still feel I get a taste of what they experience.
During forest runs, you do get those split second decision moments and you must also be in good enough physical shape to perfectly react to the decision (which usually makes the difference between scoring a nice jump off a snow hill between two trees, or ending up face first into a big tree trunk).
It's a good way to be tuned to your body and be able to know what shape you're in at any moment in time (at the precise moment you need to do something tricky, if you're getting exhausted, you'll get sloppy, missturns, and generally hurt yourself pretty badly if you don't get the hint quickly enough and back down on tricky riding)

Then again, regardless, if you're going off the groomed trails, you'll want:
  1. a helmet. Don't even argue, your skull and face are valuable
  2. solid googles (saves your face and eyes from scaring if you get a branch in the face)
  3. wrist guards (no matter how good you are, you will use your hands when you lose balance off a 60 degree slope, if you happen to fall in some unexepected fashion). Too many snowboarders break their wrists, you don't want to be the next one, it really sucks

Turns out that just today, on my one but last run, I did a nice jump off a flat crossing path for people who need a green way back home, but didn't see the small pine tree that was diagonally in my landing zone.
I managed to land on my board and back to slow down and mostly avoid it, but its branch hit me in the face pretty hard. It threw my goggles off, and moved my helmet on my head. That said, I didn't get hurt in any way thanks to those two protections.
If you're adventurous, this could happen to you, so wear your protection :)
2004/02/21 Another cool link on highway safety and speed
π 2004-02-21 20:11 by Merlin in Cars

Current Music: Armin Van Buuren, A State of Top 20 (Armin absolutely rules)
Current Mood: Fair (tired from a snowboarding day with not enough sleep, good snow though)

A quote from a friend: "France and Germany expect more of their drivers so they get it, we expect the least and get it."

Anyway, on a car list I'm on, they posted another nice article on the stupidity of low speed limits.
Let me quote the best part:
"Applying numbers to the most accredited relative risk bell curve, by Cirillo, tells an interesting story. This curve was based on urban interstate research during off peak hours. It found the safest speed to be the mean plus 12 mph, and when charted on the graph the safest speeds extended up to the mean plus 18-20 mph.

Translated, the current mean on most rural interstates is between 70-75 mph and the safest speed would be 82-87 and the vehicles least likely to be involved in an accident are those traveling between 70 and 93-95 mph. The current speed limits are set so low that the vehicles least likely to be involved in an accident, according to the studies, are the primary targets of enforcement during the best highway conditions.

Should the limit be set at 90 or 95 mph? Either way, it would seem to have no effect on accident rates. The Montana and Autobahn real life experience of unposted limits having no apparent effect on safety can not be ignored."
2004/02/20 What to do if you got a ticket, and how to avoid them
π 2004-02-20 15:45 by Merlin in Cars



Here is original post, which triggered the "well, you could drive slower" response (see below)

If you get a ticket, go to these places:
  1. http://ticketassassin.com
  2. http://www.helpigotaticket.com/
    (Geo, the author is paralegal and better at answering Emails than Patrick from ticketassassin)
  3. NMA, the national motorist association http://www.motorists.com/issues/tickets/
    You should become a member for $30/y or so, and you can get lots of useful info (they'll even pay your ticket if you fight it and lose)

You should also seriously consider:
  1. a good radar detector, not a fake $50 one: http://www.valentine1.com/ (not cheap, but paid for itself several times for me already)
  2. train yourself to scan for cop hideouts and signs of enforcement (as well as tips like, increased enforcement at the beginning and the end of each months as each officer meets illegal ticket quotas)
    You'll also be a safer driver by paying more attention to the road and your rear view mirror
  3. you can also plea bargain with the judge before the court date by mail for a 2nd traffic school within 18months, which is a lot cheaper than $1500-$3000 in increased insurance over 3 years
2004/02/20 About speed limits and enforcement
π 2004-02-20 15:30 by Merlin in Cars

Well, I didn't last a week without ranting about speed limits or enforcement thereof.
But that's not my fault, someone at work taunted me saying that one wouldn't get tickets if one drove the speed limit. Arghhhh....

So, here's the answer he got (and that I can refer to for next time):
  1. you can get pulled over and ticketed without violating traffic laws (I have been, by a cop driving 100mph in the slow lane, and pulling me over because I crossed it and made him slow down when I was exiting on an off ramp while properly signaling and driving 60mph)
  2. you may be impeding traffic while driving the speed limit (california as strange and interesting laws about those cases).
  3. The speed limit in cities may not actually be legal and properly supported by traffic surveys
  4. there are enough traffic laws that you don't know about (not counting the ones you do know) that you're most likely violating at least one every time you drive somewhere, so driving the speed limit doesn't mean in any way that you can't and won't be ticketed.
  5. Ticket quotas and speed traps are illegal in california, but both are practiced anyway, leaving you with the only options of fighting or paying when it happens to you.
  6. several studies have shown that 80mph speed on the freeway (which is what many other countries have) isn't actually a problem for properly educated drivers (actually they have a lower crash rate)
    http://www.autospeed.com/cms/article.html? &A; =1234
    http://www.hwysafety.com/hwy_montana_2001.htm
    http://www.ibiblio.org/rdu/a-facdec.html
    http://www.ibiblio.org/rdu/sl-irre0.html
    http://www.ibiblio.org/rdu/sl-irrel.html
    http://www.hwysafety.com/brief_mi_fptenents.htm
2004/02/15 Binary hacking bru backup to work over NFS
π 2004-02-15 23:14 by Merlin in Linux

What follows is unix centric, and won't tell you much if you're not a programmer/unix user, but you should enjoy it otherwise (please note that I do own a legal copy of bru backup for personal use, which I got with an old boxed set of Red Hat)


I'm trying to get my backup tape library to work as I've never been able to backup the 1TB+ of media files (don't ask) I have (I've been copying them on my other drives, but now I have too many for that to fit)

So, I decided to move my tape library to another machine, just for testing (to see if the library was bad, or my SCSI connection or host PC was flaky)
But, problem, it wouldn't back up a single file over NFS.

After a while, I realized:
gargamel:~# bru --version
bru: invalid option -- -
usage: bru -cdeghitx [-#AabBCEfFGjlLmnNoOpPQRSsuUvVwXYZ] file(s)...

Copyright (c) 1994-97, Enhanced Software Technologies, Inc.
All Rights Reserved

BRU is a backup software product licensed by EST.
It is NOT public domain or shareware. Versions are
available for almost any type of Unix system.

This is the Personal Edition version of BRU 2000. It does not offer
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
support for backup or restore of remote/network filesystems.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
To order a copy of the full version of BRU 2000 or for further
information or technical support, please contact Red Hat Software

Ah, great.
There had to be a way to trick it to backup over NFS anyway (this software is more than 7 years old, I'm probably not able to buy a license today, and I'm not violating the spirit of the license, I'm just doing a backup of one system, but without being able to have the library connected to it)

So, I did a couple of straces, one of a local file and one of an NFS file and diffed them.
What did I see?

open("/bru/.serial_number", O_RDONLY) = -1 ENOENT (No such file or directory)
uname({sys="Linux", node="host.svh.domain.tld", ...}) = 0
-lstat64(0x806e5a4, 0xbffff298) = 0
-lstat64(0x8070978, 0xbffff280) = 0
-statfs("dshelf3_X10:D3_MD5_.bz2", {f_type="NFS_SUPER_MAGIC", f_bsize=8192,
f_blocks=14836773, f_bfree=1564919, f_files=15073280, f_ffree=14353562,
f_namelen=255}) = 0
^^^^^^^^^^^^^^^^^^^^^^^
-lstat64(0x8070978, 0xbfffee1c) = 0
-access("dshelf3_X10:D3_MD5_.bz2", R_OK) = 0
+lstat64(0x806e5a4, 0xbffff2a8) = 0
+lstat64(0x8070978, 0xbffff290) = 0
+lstat64(0x8070978, 0xbfffee2c) = 0
+access("profile", R_OK) = 0
+lstat64(0x8070978, 0xbfffe6f0) = 0
+access("profile", R_OK) = 0
+open("profile", O_RDONLY|O_NONBLOCK) = 4
+write(1, "c 4k of 6k [1] profile\n", 27) = 27


Aaahahh. man statfs said that NFS_SUPER_MAGIC was 0x6969, which is "ii" in ascii.
So, I just opened the bru binary with vi, found one instance of "ii" (I was lucky) and it was around the text strings, so it was definitely in the variable sections of the binary.
I changed the string to "ij", and voila, nfs backups.

Yeepee! :)

The joys of a simple geek may be hard to convey sometimes :)

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