Word to the wise:

Don't put your PowerBook through a US security scanner at the airport
while it is asleep.

I just went to a conference in the US. The machine was asleep when I
went through airport security in the UK, and came out none the worse for
wear. I used it while I was at the conference, and all seemed well.

On the way back, did the same again. Machine was asleep, through the
scanner it went. This was on Sunday.

On Tuesday, I woke the machine up again. Every single application that
had been running crashed (although the OS seemed to survive).

The machine remained usable for the rest of the day, so I thought
nothing of the crashes at wake-up.

However, last night and this morning I ripped a couple of CDs. Half way
through ripping a song, the machine suddenly reverted to the login
window. I logeed in, tried to rip the song again, and the same thing
happened. On the third attempt it worked.

Suddenly, several applications stopped working. I tried to log out. I
couldn't. I tried to shut down. I couldn't. Eventually had to power
cycle the machine. It now boots, as far as starting the window server,
but never produces a login window. Logging in over ssh, the system was
logging some interesting errors; crashdump was running dozens of times a
minute, and being killed with SIGTRAP.

I switched it on in FireWire target mode, attached it to a friend's Mac,
and ran Repair Permissions. This took *hours*; thousands of files had
incorrect permissions.

The machine still wouldn't boot. fsck in single user mode reported many
overlapping extents (find / -inum identified them as mostly being in the
recently ripped CD tracks).

cron was reporting that it couldn't parse my crontab - I looked at the
crontab file, and discovered it was now just binary data.

I tried to switch off journalling on the root filesystem, but diskutil
refuses to run, as do many other applications.

My hypothesis is that the following happened:

The sleeping machine's RAM was basically trashed by the US X-ray machine
(which is much more powerful than those used in the UK). On waking up,
most applications fell over, but more insidiously the OS's metadata
about the filesystem was corrupted. As I used the machine yesterday and
this morning; this successively corrupted more and more of the
filesystem, until eventually system libraries and frameworks were
affected and the whole thing fell over.

This has also happened to another Mac user here who went on a business
trip to the US, so this isn't a lone case, although in his case the
corruption was much less severe, and DiskWarrior was able to fix it.
However, it looks like a full format and restore for me.

My latest backup on my iPod is from yesterday, so is probably buggered
as well, but I have a slightly older one on another system, fortunately.

Anyway, be warned. Shut down your PowerBook completely before letting
it go anywhere near a US security scanner. This may sound obvious with
20-20 hindsight, but I've got rather used to thinking of my Mac as being
"off" when it's asleep...

Tim

Tom Harrington <tph[at]pcisys.no.spam.dammit.net> wrote:
> Tim Cutts <timc[at]chiark.greenend.org.uk> wrote:
>
>> Word to the wise:
>>
>> Don't put your PowerBook through a US security scanner at the airport
>> while it is asleep.
>
> Barring more reports of the same kind of thing, I have to consider the
> timing of your troubles to be coincidental, or perhaps related to
> shaking of the hard drive that may have occurred in transit.

I also suggest that it is coincidental. I've taken my iBook and
now my TiBook on numerous US trips (usually via O'Hare) with no problems.
I always have it in sleep mode so that I can fire it up quickly
if requested to do so. Given the huge number of people who take
laptops with them every day, a true cause and effect would cause
hourly posts.

In article <9xk*5lmWp[at]news.chiark.greenend.org.uk>,
Tim Cutts <timc[at]chiark.greenend.org.uk> wrote:

>The machine still wouldn't boot. fsck in single user mode reported many
>overlapping extents

Ah well... I've got those. I went nowhere near a security check; just did
the combo update to 10.2.6.

I copied my user directory to my OS9 partition (using the OS9 finder copy)
and it all came across without complaint, so I'm hoping that my saved copy
is straight... Waiting to get DiskWarrior, but anticipating an intitialise
and reinstall.

--
Peter

In article <bdv4hs$iaa$1[at]mozo.cc.purdue.edu>, anonymous[at]mac.com wrote:

> Tom Harrington <tph[at]pcisys.no.spam.dammit.net> wrote:
> > Tim Cutts <timc[at]chiark.greenend.org.uk> wrote:
> >
> >> Word to the wise:
> >>
> >> Don't put your PowerBook through a US security scanner at the airport
> >> while it is asleep.
> >
> > Barring more reports of the same kind of thing, I have to consider the
> > timing of your troubles to be coincidental, or perhaps related to
> > shaking of the hard drive that may have occurred in transit.
>
> I also suggest that it is coincidental. I've taken my iBook and
> now my TiBook on numerous US trips (usually via O'Hare) with no problems.
> I always have it in sleep mode so that I can fire it up quickly
> if requested to do so. Given the huge number of people who take
> laptops with them every day, a true cause and effect would cause
> hourly posts.

Another point to be aware of is that your laptop is supposed to be OFF
for take off and landing according to most airlines. Asleep is NOT the
same as off so you should not be travelling with your laptop in the
sleep state.

Dare I say this but windows has an extra state called hibernate in which
the contents of memory are dumped to disk and the machine is then truly
switched off. However on power up the memory is restored from disk with
all active applications restored to their previous running state. This
is a much faster start than a true boot although a little slower than a
wake from sleep and still preserves work in progress.
The second advantages of hibernate over sleep is that, being truly off,
it consumers absolutely no battery and is therefore can be held for as
long as you wish, even through the complete removal/replacement of the
batteries.

Alan
====
ACHTUNG!!!
Das machine is nicht fur gefingerpoken und mittengrabben. Ist easy
schnappen der springenwerk, blowenfusen und corkenpoppen mit
spitzensparken. Ist nicht fur gewerken by das dummkopfen. Das
rubbernecken sightseeren keepen hands in das pockets. Relaxen und vatch
das blinkenlights!!!

In article <bdv4hs$iaa$1[at]mozo.cc.purdue.edu>, <anonymous[at]mac.com> wrote:
>
>I also suggest that it is coincidental. I've taken my iBook and
>now my TiBook on numerous US trips (usually via O'Hare) with no problems.
>I always have it in sleep mode so that I can fire it up quickly
>if requested to do so. Given the huge number of people who take
>laptops with them every day, a true cause and effect would cause
>hourly posts.

Hmm, well this has only happened to one other person I know, and it was
in exactly the same circumstances; returning from a business trip to the
US.

You may be right, of course.

Following a full reinstall, my machine is happy again though, so I don't
think it was a hardware problem.

Tim

Tom Harrington <tph[at]pcisys.no.spam.dammit.net> wrote:

> In article <9xk*5lmWp[at]news.chiark.greenend.org.uk>,
> Tim Cutts <timc[at]chiark.greenend.org.uk> wrote:
>
> > Word to the wise:
> >
> > Don't put your PowerBook through a US security scanner at the airport
> > while it is asleep.

<snip>

> Barring more reports of the same kind of thing, I have to consider the
> timing of your troubles to be coincidental, or perhaps related to
> shaking of the hard drive that may have occurred in transit.

<snip>

While I would normally agree with you I had the oddest experience with
my Powerbook while travelling recently - going to the US was fine, the
PB was asleep, and was fine in many, many Starbucks in San Francisco
(the wireless access there, unlike the coffee, is really rather good,
though not free, but T-Mobile offers a free trial)

The problems started when I left SF for Fiji - we had to go via SF
airport to LAX, which involved at least three X-Rays. When I got to Fiji
the Powerbook's date was reset an entire month ahead (which will explain
an post about Internet Explorer's demise that will pitch up here any day
now). Resetting the date worked fine, and I reset the PRAM just in case.

That fixed the problems, and it stayed fine until I went through Fiji's
international airport at Nadi. On checking the machine while in flight
once again the date had been set ahead.

Flying from Sydney to Brisbane, however, caused no problems. So, to sum
up, the problems with the pram *seemed* to have been caused by the x-ray
machines at some airports. My better judgement says that they didn't,
but I'm erring on the side of caution and will be checking the PB very
carefully next time I travel to the US...

ck

--
__________________________________________________________
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In article <1fxjhda.1egod7wiuebd8N%charles_kooy[at]despammed.com>,
charles_kooy[at]despammed.com (Charles Kooy) wrote:

> The problems started when I left SF for Fiji - we had to go via SF
> airport to LAX, which involved at least three X-Rays. When I got to Fiji
> the Powerbook's date was reset an entire month ahead (which will explain
> an post about Internet Explorer's demise that will pitch up here any day
> now). Resetting the date worked fine, and I reset the PRAM just in case.

Hmm, maybe your powerbook is unusually sensitive to crossing the
dateline? ;-)

Peter

--
Peter Ashby
School of Life Sciences, University of Dundee, Scotland
To assume that I speak for the University of Dundee is to be deluded.
Reverse the Spam and remove to email me.

OK, so it seems you guys might be right; there may be a hardware or
software problem here.

I have now reformatted and reinstalled my PowerBook from scratch.

However, the machine hangs after a few minutes. Any program which tries
to access the disk hangs for ever. I can't even force it to quit.

I booted the machine with the hardware test CD, and all the hardware
checks out fine in that.

I then checked the power saving settings. They were set to spin the
hard disk down when possible. I switched that feature off, and now the
machine seems fine.

It would appear that the machine can no longer spin the hard disk up
once it has spun it down. Has anyone heard of this problem before? Is
it a known issue?

I'll go and check the machine has the latest firmware installed, but it
sounds to me like the hard disk may be on the way out. Thoughts?

Tim

Tim Cutts <timc[at]chiark.greenend.org.uk> wrote:

> I have to agree that this full form of hibernation that PCs do is a very
> useful feature, and one of the few things I miss from my PC laptop.
> Apple would be well advised to add this feature to OS X.

<AOL> me too </AOL>

-z-

--
"I'm not sure how useful this is, but it's bloody clever."
- Jonathon Sanderson in uk.comp.sys.mac
Are you posting responses that are easy for others to follow?
http://www.greenend.org.uk/rjk/2000/06/14/quoting

In article <5JNNa.393528$Vi5.10146570[at]news1.calgary.shaw.ca>,
Steven Fisher <sdfisher[at]spamcop.net> wrote:
>Tim Cutts wrote:
>
>> I have to agree that this full form of hibernation that PCs do is a very
>> useful feature, and one of the few things I miss from my PC laptop.
>> Apple would be well advised to add this feature to OS X.
>
>I used to think so, too, but I've since noticed that it's faster for me
>to shut down and restart (including all apps) than hibernate.

I suppose that depends on what you're doing. For me, I agree with you -
I tend to close down everything that I'm doing at the end of each day;
I'm not one of these people who leaves bazillions of windows open all
the time (largely because most of them are Terminal sessions logged into
other machines, so they don't usually survive sleep anyway).

However, it does give your machine an emergency behaviour mode if its
battery runs down completely while it's running lots of things. That
has happened to me in the past, although not on my Mac yet, thank
goodness...

Tim

Tim Cutts wrote:

> However, it does give your machine an emergency behaviour mode if its
> battery runs down completely while it's running lots of things. That
> has happened to me in the past, although not on my Mac yet, thank
> goodness...

I dunno. If you ever get that low on power, you're never going to be
able to write (for instance) 512 MB of data to disk before turning off
power. I'd prefer a sleep that doesn't take much power.

Tim Cutts wrote:

> In article <C+i*WTvWp[at]news.chiark.greenend.org.uk>,
> Tim Cutts <timc[at]chiark.greenend.org.uk> wrote:
>
>>It would appear that the machine can no longer spin the hard disk up
>>once it has spun it down. Has anyone heard of this problem before? Is
>>it a known issue?
>
>
> Known issue or not, resetting the PMU seems to have fixed the problem.

Glad you got it.

Charles Kooy wrote:
>
> Tom Harrington <tph[at]pcisys.no.spam.dammit.net> wrote:
>
> > In article <9xk*5lmWp[at]news.chiark.greenend.org.uk>,
> > Tim Cutts <timc[at]chiark.greenend.org.uk> wrote:
> >
> > > Word to the wise:
> > >
> > > Don't put your PowerBook through a US security scanner at the airport
> > > while it is asleep.
>
> <snip>
>
> > Barring more reports of the same kind of thing, I have to consider the
> > timing of your troubles to be coincidental, or perhaps related to
> > shaking of the hard drive that may have occurred in transit.
>
> <snip>
I recently took a sleeping PowerBook 17" through X-ray scans at Gatwick,
Singapore, Sydney, Melbourne, Auckland, Los Angeles, Chicago and Tampa,
and had not a single problem after any of those.

Of course, this might have something to do with different casing
materials on the laptop, but I suspect not.

My experience suggests that PowerBooks are more at risk from the big AC
magnetic fields around escalators and moving walkways than they are from
X-ray scanners. As a pointer to their strength, I have certainly had
more than one VHS videocassette effectively trashed, while in a bag that
was set down on one or other of those 'conveniences' at airports.

--
From Gareth John - please cut the Twaddle
if you want to reply by email.

As to airport security, I cannot speak to the corruption but
I can speak to something else: Do not put it through while asleep
because if your latch were to come open, say, while the machine
is bouncing down those freaking warehouse rollers at the discharge
end of the Xray device why you'd be trying to spin up your disk
drive while it was getting its teeth rattled. If you did that,
you might lose the drive altogether.

Ask me how I know.

--dan

In article <me2-3DBF5C.00223103072003[at]news.fu-berlin.de>, Alan Goodman
<me2[at]privacy.net> wrote:


>
> Another point to be aware of is that your laptop is supposed to be OFF
> for take off and landing according to most airlines. Asleep is NOT the
> same as off so you should not be travelling with your laptop in the
> sleep state.


Please.... are you trying to be anal?

--
germ Remove "nospam" to reply