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ChipMcK
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BootCamp Extended Partition not same as in Windows

Created BootCamp Vista. Once installed, did a shrink of the partition and then created an Extended Partition with a Logical partition inside.

Rebooted Mac and started Fusion. Fusion created the Boot Camp Partition and after updating the settings (no printer, no auto USB), started up the VM.

In Windows Vista BC (32bit if interested) started Computer Management and selected Disk Management.

The Extended Partition does not have the Logical partition inside. In fact, it is outside of the Extended Partition.

What havoc will this cause?

Attached JPEGs from Vista and Vista BC of Disk Management window show partition layouts

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mudaltsov
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When you shrunk the Windows partition and created additional partitions, the MBR (master boot record) partition table was modified to include the extended partition, and EBR (extended boot record) partition tables were created to reference the logical partitions. However, the GPT partition table that OS X uses has not been updated, so OS X cannot see the new partitions, and Fusion won't be able to use them for the Boot Camp VM either.

This is basically the same issue as in . This type of hybrid GPT and MBR/EBR configuration is not very safe, because two different partition tables may present different areas on disk as free space, potentially overwriting each other when they are modified.

There are a few possible solutions:

A. Convert your disk to MBR only, without GPT. In my experience it works fine, and OS X can boot correctly, but I don't think Apple officially supports booting OS X from an MBR partitioned disk. You also lose the ability to resize partitions in Disk Utility (though it might not be safe to do anyway).

B. Update your GPT partition table to include the new partitions, and leave the MBR/EBR entries as they are. This will achieve the same results, but might not be very stable for long term use. This would require some custom editing of the partition tables (which is what I did in the thread referenced above).

C. Update your GPT partition table to include the new partitions you added, and re-write the MBR to only have 4 primary partition entries. One of them must be reserved for a protective partition that hides OS X, but the other 3 can be used for the Windows partitions. This can be accomplished by GPT fdisk, if you're very careful. I think overall this is the safest method, since it doesn't rely on keeping the EBR entries.

ChipMcK
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Hot Shot

A new release is weeks away. I think I will wait for it and then see what mischief I can experience.

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mudaltsov
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Are you talking about the upcoming release of Fusion 3?

That won't help the problem that you're running into. Your current partition configuration makes it impossible for OS X to see the modified partitions that you added using Windows Disk Management, so Fusion won't be able to see them either.

As a test, you can run diskutil list in Terminal, and you should see that it only shows the Windows partition that was created by Boot Camp Assistant, not the new partitions that you added afterwards.

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ChipMcK
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If the windows partition is "sufficiently marginal" and the system (OS X) partition is "sufficiently marginal",

then perhaps, what is in the middle will be sufficient for my purposes with/in the new release.

(I erred, less than two weeks.)

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ChipMcK
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I just noticed that you seem to have not committed on the placement of of the Logical partition, namely outside the EBR - not inside.

The .vmdk files were generated after the creation of the windows partition - the 'raw...' process had full access to the GPT/MBR/EBR data

and yet did not properly represent the data.

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mudaltsov
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I'm not quite sure what you mean by "sufficiently marginal"... I'm assuming you'd like to get the Boot Camp VM to a working state so it sees all your partitions? I'm willing to help with that. As I mentioned before, there are several solutions. The best option would depend on exactly which configuration you'd like to have, and what you want to do with the free space on the disk. Are you planning to add another partition at some point, or resize the existing one? Any future manipulations to the partition table become complicated if you want to keep a hybrid GPT and MBR partition table.

I just noticed that you seem to have not committed on the placement of of the Logical partition, namely outside the EBR - not inside.

The .vmdk files were generated after the creation of the windows partition - the 'raw...' process had full access to the GPT/MBR/EBR data

and yet did not properly represent the data.

The vmware-rawdiskCreator utility should properly read MBR and EBR data, and can create a vmdk that references any of the partitions (Primary or Logical). It does not currently use the GPT data directly. However, if the GPT data does not have all the partitions defined, OS X won't be able to use those partitions, and as a result, rawdiskCreator won't be able to use them either. I'm not sure why the Boot Camp screenshot shows the 39 GB partition as Primary instead of Logical.

The difference between rawdiskCreator in Fusion 2 and Fusion 3 is support for creating a vmdk that references multiple partitions. However, this can still be accomplished in Fusion 2 by manually editing the vmdk files.

So, a few questions:

1. What's your plan for the free space on the 232.88 GB disk? Do you want to make another partition, extend the 39.06 GB partition to fill that space, or leave it empty for some other reason?

2. Do you need to keep the extended partition layout, or are you fine with making all the partitions primary? This is limited up to 3 primary partitions assuming one more is used to hide the HFS partition (generally preferred to keep the OS X data safe from accidental changes).

3. Are you planning to change the partition layout again in the future? Any changes would need to be done for both GPT and MBR partition tables. I think the best approach is to partition using GPT, and synchronize the MBR (again, with the limitation of Primary partitions).

4. Do you want to access the 298.09 GB disk from the Boot Camp VM, as you do when running natively? It looks like you have both NTFS and HFS partitions as F: and G:. This isn't directly related to making the first disk usable, but I though it would be good to know.

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ChipMcK
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The vmware-rawdiskCreator utility for v206 is not working as intended, yes?

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mudaltsov
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It works as intended for Fusion 2 - it was created as a tool that enables Boot Camp support in Fusion for a single Windows partition. Most Boot Camp installations only need a single partition (and Apple officially only supports a single Windows partition on the same drive as OS X), so multiple partitions wasn't an issue. Anyone interested in creating virtual disks that use more than one physical partition can do so regardless of the capabilities of rawdiskCreator, it just takes more work.

After getting feedback about using multiple partitions, especially on a separate physical disk (fully used for Windows, not OS X), we have decided to improve rawdiskCreator in Fusion 3 to allow multiple partitions. One important use case that this enables is Windows 7, which creates an additional "System Reserved Partition" when installed on an empty hard drive.

It's possible that we may provide the same multiple partition support to rawdiskCreator in a future 2.0.x update, but it's not really necessary. Once Fusion 3 comes out, anybody could just get rawdiskCreator from Fusion 3 and use it to create vmdk files with multiple partitions. Those vmdk files are fully usable in Fusion 2.

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mudaltsov
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And I'd like to re-iterate that the multiple partition support in rawdiskCreator will not be enough to resolve your issue. The GPT partition table need to be updated to properly include the new partitions, so that OS X can see the new partition you added in Windows.

I can help you with that, but before I can provide more instructions I need answers to the questions I posted earlier.

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ChipMcK
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For what I had in mind, OS X can be obvious, but Fusion may not be obvious - the partition configuration needs to be accurate.

That said - what other configurations might meet my desires/wants/ideas - without requiring a hoop or three? What you said about R3 hints at some possibilities.

In approx ten days I will be able to experiment with the R3 product. Anticipation! Isn't that a salesman's delight?

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