Jump to content











Photo
- - - - -

Easy2Boot Partition Alignment ‘ Overlapping Concerns


Best Answer Noer5 , 30 January 2015 - 12:08 PM

Oh, I see what is happening !
Easy2Boot is redefining the UFD’s partitionS based on the actual ‘physical’ position(s) of its image file(s).
Strange and simple, but safe.
The coincidence was throwing me off, and so thought the original UFD PTN positions were being retained.
If I had resized my original UFD partitions to where PTN1 was say 7 GB, then that would have forced the move of the .imgPTN file to a different ‘physical’ location.  And then Easy2Boot would have defined the space where PTN1 was as 7+ GB  to account for the loaded .imgPTN file’s new position.

The start and size of the partition in CSM mode is the start of the .imgPTN file (wherever it happens to be on the drive) and the size of the .imgPTN file (i.e. the file size).

THANKS
 

Go to the full post


  • Please log in to reply
7 replies to this topic

#1 Noer5

Noer5

    Member

  • Members
  • 34 posts
  •  
    Tahiti

Posted 29 January 2015 - 01:29 AM

I used a combination of two different tutorials to build a Windows To Go 8.1 on ‘Removable’ Easy2Boot Drive.
I started out with (in normal mode):
PTN1 FAT32 = 5 GB
PTN2 NTFS = 30 GB

Booted to CSM mode a couple times to check out.
Decided to resize partitions because couldn’t figure out why PTN1 (normal mode) needed to be 5 GB.

Switched back to normal mode > first HDD > resized partitions:
PTN1 FAT32 = 300 MB - - - (an ‘MS System’ partition for boot managers ‘ loaders)
PTN2 NTFS = 60 GB - - - (for Easy2Boot & payload files, becomes PTN1 in CSM mode)
Did not create PTN3 or PTN4 since directed to leave those entries blank for Linux ISOs.

Anyway, so now, when in CSM mode, it still shows (similar to the normal mode that I first booted to):
Unallocated = ~5 GB (rather than 300 MB)
PTN1 NTFS = ~30 GB (rather than 60 GB)

This makes for some serious partition overlapping between CSM mode and normal mode.
Thus my concern that some sectors will be overwritten between modes.
Is there a way to accurately realign partitions between modes?
I’m guessing that Easy2Boot adopted this CSM mode partition layout (from normal mode) when it was first booted to CSM mode?  And then just kept it that way.

Thanks
 



#2 steve6375

steve6375

    Platinum Member

  • Developer
  • 6954 posts
  • Location:UK
  • Interests:computers, programming (masm,vb6,C,vbs), photography,TV,films,guitars, www.easy2boot.com
  •  
    United Kingdom

Posted 29 January 2015 - 09:03 AM

Don't quite understand you.

Did you read http://www.easy2boot.../how-e2b-works/  (bottom of page)

 

In CSM mode, the previous partitions are replaced  (unless you have used .imgPTN23 family of extensions instead of .imgPTN).

 

The start and size of the partition in CSM mode is the start of the .imgPTN file (wherever it happens to be on the drive) and the size of the .imgPTN file (i.e. the file size).

 

There is no overlap in any one mode.

 

No need for two partitions in E2B mode - just a single NTFS partition will be fine. This can hold a .imgPTN file which should be a NTFS-formatted partition image (made using the MakePartImage desktop shortcut and specify it's size manually).

Select the .imgPTN file in the E2B menu and run it so that you get to CSM mode and the CSM menu.

Ptn1 will now be the size of your .imgPTN file and can contain your \boot folder, \bootmgr and your .vhd file.

 

The other alternative is to not use a .imgPTN file at all. Just add the \boot folder, \bootmgr file and .vhd file to the root of your E2B NTFS drive and add a .mnu file which will boot to \bootmgr straight from the E2B partition.


Edited by steve6375, 29 January 2015 - 10:57 AM.


#3 Noer5

Noer5

    Member

  • Members
  • 34 posts
  •  
    Tahiti

Posted 29 January 2015 - 11:54 PM

Don't quite understand you.

Did you read http://www.easy2boot.../how-e2b-works/  (bottom of page)

 

In CSM mode, the previous partitions are replaced  (unless you have used .imgPTN23 family of extensions instead of .imgPTN).

 

The start and size of the partition in CSM mode is the start of the .imgPTN file (wherever it happens to be on the drive) and the size of the .imgPTN file (i.e. the file size).

 

There is no overlap in any one mode.

Yes, read that several times now and get every point you made.

It's not in any one mode that concerns me.

It is the overlap between modes.

I made a good jpeg of this, showing UFD in both modes for comparison, but can't see a way to upload it to my "Media Library" -- to get a URL.

Thanks

edit:>> I understand that the CSM MBR replaces the normal MBR, but don't see how the same sectors can have dual use -- where partitions overlap between modes.

Used this site to host image. Hope that's ok.

UFD-e2b-Both-Modes.jpg  <<<  Use the Slow Download button.


Edited by Noer5, 30 January 2015 - 12:52 AM.


#4 Noer5

Noer5

    Member

  • Members
  • 34 posts
  •  
    Tahiti

Posted 30 January 2015 - 12:57 AM

http://www.speedysha...-Both-Modes.jpg  <<<  Use the Slow Download button.

Edit = Please delete jpg link in above post as it will not work that way.

Thanks


Edited by Noer5, 30 January 2015 - 01:01 AM.


#5 steve6375

steve6375

    Platinum Member

  • Developer
  • 6954 posts
  • Location:UK
  • Interests:computers, programming (masm,vb6,C,vbs), photography,TV,films,guitars, www.easy2boot.com
  •  
    United Kingdom

Posted 30 January 2015 - 09:08 AM

There is no 'overlap'

 

The .imgPTN file starts at 5.8GB on the drive and is 28.7GB in size. It is in the same place in both modes. How can there be overlap when it is in the same place in both modes?



#6 Noer5

Noer5

    Member

  • Members
  • 34 posts
  •  
    Tahiti

Posted 30 January 2015 - 12:08 PM   Best Answer

Oh, I see what is happening !
Easy2Boot is redefining the UFD’s partitionS based on the actual ‘physical’ position(s) of its image file(s).
Strange and simple, but safe.
The coincidence was throwing me off, and so thought the original UFD PTN positions were being retained.
If I had resized my original UFD partitions to where PTN1 was say 7 GB, then that would have forced the move of the .imgPTN file to a different ‘physical’ location.  And then Easy2Boot would have defined the space where PTN1 was as 7+ GB  to account for the loaded .imgPTN file’s new position.

The start and size of the partition in CSM mode is the start of the .imgPTN file (wherever it happens to be on the drive) and the size of the .imgPTN file (i.e. the file size).

THANKS
 


Edited by Noer5, 30 January 2015 - 12:12 PM.


#7 steve6375

steve6375

    Platinum Member

  • Developer
  • 6954 posts
  • Location:UK
  • Interests:computers, programming (masm,vb6,C,vbs), photography,TV,films,guitars, www.easy2boot.com
  •  
    United Kingdom

Posted 30 January 2015 - 12:22 PM

On an E2B drive, ptn #4 must always be empty/free.

E2B just uses the partnew grub4dos command to make a new partition table entry at the ptn #4 position - E2B then deletes the current partition entries and moves the ptn #4 entry to the ptn #1 position in the partition table.

The MBR boot code is not affected and so it still looks for and boots to \grldr and grub4dos - so I ensure a grldr and a \menu.lst file is present in the image first before changing the partition table.

If you use the .imgPTN23 file extension, then the current ptn #2 and ptn#3 are not deleted from the partition table so they will also be accessible in 'CSM mode'.



#8 Noer5

Noer5

    Member

  • Members
  • 34 posts
  •  
    Tahiti

Posted 30 January 2015 - 04:17 PM

AWESOME !

Added '23' to extension of main WTG image file to get WTG81u3.imgPTN23 .

Had only PTN1 & PTN2, and PTN2 had the image files, so it shows PTN1 (CSM PTN1) and WTG image (CSM PTN2).

Also had WTG pared image  'WTG81u3' with no extension, so it also shows that image (CSM PTN3).

 

http://www33.speedys...2b-CSM-w-23.jpg

or http://www.speedysha...2b-CSM-w-23.jpg  <<<< Use the Slow Download button.

Pic is of Partition Wizard running on the WTG on this UFD.

 

Started this thread on trying to gain access to these extra PTNs from WTG:

http://reboot.pro/to...rtition-access/


Edited by Noer5, 30 January 2015 - 04:44 PM.





0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users