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Some Windows Apps Make GRUB 2 Unbootable
KwahAG writes "Colin Watson, one of the Ubuntu developers, published in his blog information about Windows applications making GRUB 2 unbootable. Users of dual-boot Windows/Linux installations may face the problem, which boils down to particular Windows applications (Colin does not name them, but users point at least to HP ProtectTools, PC Angel, Adobe Flexnet) blindly overwriting hard disk content between the MBR and the first partition destroying information already stored there, in this particular case — the 'core image' of GRUB 2 (GRand Unified Bootloader) making the system unbootable."
Nothing is supposed to be there except the user-installed system boot code, boot data, and hard drive parameters.
Third party software certainly has no business messing with Sector 0 or the boot blocks unless it gets explicit permission, advises users of the risks in messing with the boot block, prompts the user to back anything up that's there right now, and writes its bits only to the portion of the boot block that is provided for its required purpose.
It may detect bootloaders, and update their configuration, if the user accepts that, but bootloader configuration is generally stored on the boot volume not the boot block
IIRC there's a part of grub.cfg that is marked with comments to not be auto-replaced when grub takes inventory of your linux kernel versions. Put the Windows stuff in there.
Wrong, GRUB belongs in the MBR, not in some unpartioned space that is not supposed to be of use, if they have a problem with that, just keep that thing (GRUB) small or create a partition.
And yes, LILO is still supported and under development. LILO 23
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
The "boot block" is precisely one sector right at the start of the fixed disk, with some space being taken up by the primary partition table, signature, etc. The problem is not Grub (and certain Windows software) writing to this area, but writing to unpartitioned space elsewhere on the drive.
This is as wrong as looking at some filesystem, discovering that certain free blocks are unlikely to be allocated, and then using that space for storage.
Of course, Flexnet is apparently quite capable of making Windows unbootable too, at least if you're using TrueCrypt. Say no to badly-designed DRM!
It's also called "GRUB with blocklists"
You can find more here,
and in my other post
I have discovered a truly marvelous proof of killer sig, which this margin is too narrow to contain.
The big headache is FLEXnet, Adobe's "license manager". It's a specialized rootkit that gives the remote licensing system access to the machine at a low level. Which is why it tends to break things a Windows application shouldn't be able to break. On Windows, it runs a background service and contacts a remote server frequently, sending undocumented information to the remote server and accepting update commands to change software already on the computer.
FLEXnet is the successor to FlexLM, a licensing system from the 1980s. It started as a UNIX product. It's been owned at various times by Highland, Globetrotter, Macrovision, and Thoma Cressey Bravo. It was unreliable in the 1990s, and the passage of time does not seem to have improved things.
In general, it's best to avoid buying Adobe products which install the FLEXnet license server.
If I'm not mistaken, Flex is required for Photoshop, Illustrator, Dreamweaver, Flash, InDesign, and After Effects. Except for After Effects, you won't find any real professional-level alternatives for any of them.
Try telling upper management that you banned your $100 an hour designers, artists, and developers from the tools they need to do their jobs, because you were worried about bootloader compatibility and proper code behaviors.
The ______ Agenda
The way most other boot loaders have done it (including the original GRUB). Put enough code in the MBR to load the rest of the code and config out of a second location. The smart ones actually use a real partition for that, though, so no one overwrites it.
What's wrong with FAT? Pretty much everything from space inefficiency to lack of permissions to filename restrictions to reliability issues, especially after unclean shutdowns.
Also GRUB's core.img already only supports one filesystem -- whichever one is /boot (which can be FAT, GRUB can do that as well), filesystem modules for other types if necessary are loaded directly from said /boot partition.