Remove Advertisement


[Guide] Drive and Partition Images: Overview

If you're gonna create a guide... stick it in here!

Re: Drive and Partition Images: Overview

Postby Deleted User 1605 » May 31st, 2015, 10:48 pm

A little clue..

The specific error would still happen in windows.. just ignore the utility names..

Bodge99
Deleted User 1605
 

Remove Ad



Re: Drive and Partition Images: Overview

Postby Deleted User 1605 » June 1st, 2015, 8:17 am

Hello All.

I'll give a further clue.. and simplify the question.

The command is cat Linx7FullDrive.img.split.gz_* | gunzip -c > /dev/mmcblk0 . It looks complicated.

I'll take out the irrelevant stuff and simplify the filenames so that it's easier to see..

Assume that the files are called this:

myfile.gz_aa
myfile.gz_ab
myfile.gz_ac
myfile.gz_aa.sha256
myfile.gz_ab.sha256
myfile.gz_ac.sha256

In windows, what would this give you?

dir myfile.gz_* (The Linux equivalent is ls myfile.gz_* )

Bodge99
Deleted User 1605
 

Re: Drive and Partition Images: Overview

Postby Deleted User 1605 » June 1st, 2015, 1:15 pm

Hello All.

Here be dragons..

Well, the answer to the above question. I can guarantee that anyone reading this who has ever done any command line work with files (e.g. in Dos) or just about any operating system that has some form of command shell will go "Oh yes, I see it now".

Explanation of my file naming conventions:.

If I have a set of files that are specifically "linked together as part of a set" then it makes sense to have something within the filename that indicates this.
e.g. A large file named "bigfile.txt". If I decide to split this file into smaller parts (the reason is irrelevant here), then naming the file portions in this manner is a good idea. e.g.
bigfile.txt.part1 , bigfile.txt.part2 , bigfile.txt.part3 and so on.

I can then look at the filenames and identify what they are immediately. To obtain the original "bigfile.txt" all I need to do is to join all of the parts together in the correct order.

As an extension to the process of splitting files, it's often a good idea to use some means of identifying if any file corruption has occurred.
This might be either in file storage (degrading storage media etc.) or in transmission across the internet..

One of the tools that I use for consistency checking purposes creates a text file containing this information. I tend to not use a tool that embeds this information into the relevant file (e.g. Winrar or Winzip type embedded recovery records) as I often want to be able to use the "raw" file with any tool that I choose. I therefore use the same filename with an appended ".sha256". I can then immediately identify which checksum file is needed with any particular file.

In order to recreate the full drive image from compressed "parts" correctly, I need to be able to identify each part in the order that it is going to be used.
Part of the command to do this uses "wildcards".

Using the "clue" example filenames from my earlier post, I need to be able to pass each file "onwards" in the correct order.

Again from the above post (for windows),

dir myfile.gz_* will return a file listing in alphabetical order.

Specifically, the directory listing will be an alphabetically sorted list of files whose names begin with myfile.gz_

This would include a file called "myfile.gz_Part1" and also "myfile.gz_Very-Long-Name-But-Not-What-I-Want-Here".
The command has done exactly what it was told to, but not quite what I wanted it to do. Subtle difference!

To list only the files that I want (using wildcards) but not the checksum files, then I need to alter the command slightly.

dir myfile.gz_* returns this:

myfile.gz_aa
myfile.gz_aa.sha256
myfile.gz_ab
myfile.gz_ab.sha256
myfile.gz_ac
myfile.gz_ac.sha256

I only want this:
myfile.gz_aa
myfile.gz_ab
myfile.gz_ac

The correct command for this example is:

dir myfile.gz_a?

This means show all files, in alphabetical order, whose filename begins "myfile.gz_a" followed by only one character.

So... the correct extract and write command for the tablet full drive archive is:

wait for it, wait for it...

cat Linx7FullDrive.img.split.gz_a? | gunzip -c > /dev/mmcblk0

I had tested that the original command did work.. It did, until the checksum files were added to the same directory.
The "error" made the command take the first archive part, extract and write it to the drive. It then tried to do the same to the next file, which in this case was the checksum file, not the second archive part.

If anyone has managed to read this far without falling asleep then.. I award you an honorary cookie.

Sorry to waffle on again...

Bodge99
Deleted User 1605
 

Re: Drive and Partition Images: Overview

Postby Ceilidhalfie » July 18th, 2015, 5:48 pm

Hi and apologies if this is a stupid ask. I have just goosed my Linx10 - ran a few of the latest Windows updates, was requested to restart to complete and after restart the Linx10 goes into "Preparing Recovery" then "Diagnosing Your PC" then a blue screen with two boxes and nothing happens!
I am devastated - I have lost my super Wimdows 8.1 with Bing tablet - have lots of files and programs on it! I can reload most of this but first need to get the Linx10 Windows 8.1 system back - factory settings if that is what has to be.
I have discovered if I comnect my Usb/cordless mouse and keyboard, I actually get them active in the blue window. The fisrt box simply reboots (and comes back to this screen again). However, when the second box is clicked, I get a new screen with 3 icons. The first exits and boots windows, the third shuts down the Linx10 but the second tales me to another screen where I can select (I think) EFI(Dvd), EFI(usb) and EFI(built in). As I only have the latter, I selected it and got into the unix like command system.
Having read this post (and not really knowing all I am reading!), it seems I could use something along these lines to restore my precious Linx10. IS THIS POSSIBLE? IF SO, HOW DO I GO ABOUT IT -feel free to assume you are talking to a dummy!
Thanks.
Ceilidhalfie
Member
Member
 
Posts: 3
Joined: February 18th, 2015, 10:03 am
Linx Tablet: Linx 10
Retailer: eBay

Previous

Return to Guides (All Devices)

Who is online

Users browsing this forum: Google Adsense [Bot], wiremonkey and 1 guest