backups & cloning

[PJ]

Polytropon wrote:
> On Tue, 29 Sep 2009 21:26:19 -0400, PJ <af.gourmet at videotron.ca> wrote:
>   
>> But what does that mean? But ad2s1a has just been newfs'd - so how can
>> it be dumped if its been formatted?
>>     
>
> When you're working on this low level, triple-check all your
> commands. Failure to do so can cause data loss. In the example
> you presented, ad1 was the source disk, ad2 the target disk.
> You DON'T want to newfs your source disk.
>
>   
>> And what exactly does stdout mean?
>>     
>
> This refers to the standard output. In most cases, this is the
> terminal, the screen, such as
>
> 	# cat /etc/fstab
>
> will write the /etc/fstab to stdout. If you redirect it, for
> example by using > or |, you can make stdout a file, or the
> input - stdin - for another program.
>
> This is how the dump | restore process works: It leaves out
> the "use the tape" or "use the file", but instead directs the
> output of dump - the dump itself - to the restore program as
> input to be restored.
>
>
>
>   
>> What is dump doing? outputting what to where exactly?
>>     
>
> The dump program is outputting a dump of the specified partition
> to the standard output, which in this case is directly trans-
> mitted to the restore program, which "picks it up" and processes
> it = restores it.
>
>
>
>   
>> I don't see it or
>> should I say, understand this at all.
>>     
>
> Have a look at the command line again, simplified:
>
> 	# dump -0 -f - /dev/ad0s1a | restore -r -f -
>
> Run the dump program, do a full backup of the 1st partition of
> the 1st slice of the 1st disk, write this dump to the standard
> output, pipe this output to the restore program, do a full
> restore, read the dump to be restored from standard input.
>
>
>
>   
>> and then the restore is from what
>> to where?
>>     
>
> The restore program gets the dump to be restored from the standard
> input - remember, that's the output of the dump program - and
> writes it to the current working directory. That's the reason
> why you should always check with
>
> 	# pwd
>
> in which directory you're currently located, because that will
> be the place where the restored data will appear.
>
>
>
>   
>> "write error 10 blocks into volume 1
>> do you want to restart:"
>>     
>
> Could you present the command you're actually using, especially
> with where you issued it from?
>   
Duh.... I think I see where this is leading... I'm pretty sure it was
issued from / which makes it redundant, right? I should have issued it
from somewhere else, like from home, usr or whatever but not from / as
that is what I was trying to dump.... :-[
>
>
>   
>> The first time I tried with -L the error was 20 blocks...
>> Both the slices for dump from and to are same size (2gb) and certainly
>> not full by a long shot ( if I reccall correctly, only about 14% is used)
>>     
>
> I'm not sure where you put the dump file. "Write error" seems
> to indicate one of the following problems:
> 	a) The snapshot cannot be created.
> 	b) The dump file cannot be created.
>
>
>
>   
>> And what's this about a snapshot? AFAIK, I'm not making a snapshot;
>> anyway, there is no long pause except for the dumb look on my face upon
>> seeing these messages.
>>     
>
> Check "man dump" and search for the -L option. The dump program,
> in order to obtain a dump from a file system that's currently in
> use, will need to make a snapshot because it cannot handle data
> that is changing. So it will dump the data with the state of the
> snapshot, allowing the file system to be altered afterwards.
>
>
>
>   
>> As it is, I am currently erasing the brand new 500gb disk on which I
>> want to restore.
>>     
>
> Excellent.
>
>
>
>   
>> Things started out really bad... don't u;nderstand what is going on.
>>     
>
> Polite question: Have you read the manpages and the section in the
> Handbook?
>   
Yes... but my brain can't handle it all so quickly... and being as
impatient as I am, I tend to miss things on the run... it usually comes
to me sooner or later... unfortunately, it's more often later than
sooner... I've been reading the stuff in the man pages, and getting more
confused by googling... Actually, I've been trying to get things
straightened ot for at least 3 days already.
>
>
>   
>> I
>> installed a minimal 7.2, booted up and turned to another computer to do
>> some serious work. About 2 hours and 49 minutes later I notice messages
>> on the 7.2 about a page fault or something like that and then the system
>> reboots.
>>     
>
> This often indicates a hardware problem...
>   
Well, that's why I'm really checking my new disk... but it could be the
motherboard... I've always suspected it had something of a glitch in it
ever since I got it... I don't think just a slower cpu should give it so
many problems... a twin computer has the same hardware except for the
cpu and it gives far less problems - only MS related.
>
>
>   
>> Obviously with errors... but then I reboot again and it comes
>> up... I tried som copying from another disk and ended up with the disk
>> all screwed up...
>>     
>
> How that?
>
>
>
>   
>> yet the Seagate Seatools for Dos doesnt find any
>> errors on it;
>>     
>
> There's smartmontools (program: smartctl) for FreeBSD in the ports.
> It can check various errors of modern hard disks.
>
>
>
>   
>> Partition magic found an error but couldn't fix it, so now
>> Im wiping the whole thing and will try to reinstall tomorrow. Doesn't
>> make sense.
>>     
>
> What error was this?
>   
Something about a boot sector - this is not the first time I have seen
this identical error but on much older hdd's, though still satas.
This does make me think that these problems are of hardware origin -
motherboard or sata connectors - I find they are rather Disneyesque
(Mickey Mouse) or just plain flimsy.

Time to hit the sack... another day of computer frustration coming up...
I'm under pressure to lear Flash and have to set up a reliable server to
test a site I am designing and setting up. Have to do it myself... can't
afford about anything today. :-(
Thanks again for the input.