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monolithic versus split disks

comparison of both types of sparse (growing) virtual disks

monolithicSparse = a growing disk in one piece

twoGbMaxExtentSparse = a growing disk split in to pieces that have a max size of 2 Gb

The one-piece type seems to be a reasonable choice at first sight - following the simple straight logic:

one virtual disk = one file

Lets have a deeper look at the differences:

VMware name monolithicSparse twoGbMaxExtentSparse
number of dependant files 1   2 - 477
looks reasonable:
one disk = one file
what the hell are all these files good for ?

max size of single chunk


  950 Gb 2 Gb
descriptor   embedded external
handling of backups   tricky with large disks excellent
can be used from alien filesystems   unlikely likely
free diskspace required for shrinking   up to 950 Gb 2Gb
free diskspace required to merge a snapshot   up to 950 Gb 2Gb
free diskspace required to defragment the disk   up to 950 Gb 2Gb
DVD backup   easy for disksizes that fit in one piece - tricky for large disks no problem
Fat32 backup   disks smaller than2 Gb only yes
network backup via ftp, samba or cifs   unreliable no problem
skills required to fix simple errors   very advanced easy
probabilty that a users messes up the disk with manual editing   very high low
tool required for basic manual editing   Windows: dsfo.exe / dsfi.exe
Linux: dd
simple texteditor
encryption embedded descriptor can be encrypted    
  not suitable for a default choice

editors choice for average usage


VMware Workstation uses the monolithic-disk type as a default.
This is not very userfriendly - especially for beginners.




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