Dual Boot: partition vs separate disk?

In setting up a dual boot system, is there any advantage or disadvantage to setting it up on one disk with partitions vs. using separate disks for each OS. My thinking is that any operating system technically sees partitions as separate disks, so partitions on one disk should look and feel like separate disks. Wrong?

I am planning to set up one dual system with Vista and XP, and another system with two XP installs. From what I have read here, setting up Vista-XP dual boot is not a slam dunk operation with OSS, so I am looking for the simplest approach, even if that means not using OSS.

 

If you are throwing Vista into the mix (which you are), then realize that most likely any Disk Swapping features won't work. Vista won't boot properly if you using that option with OSS. If you use Disk Swapping with Grub4DOS or BING, Vista will boot, but nothing is swapped. It's best to just not use the swapping feature with Vista.

Personally, I prefer using separate partitions. Each OS on its own partition which is Active to boot it and all other OS partitions Hidden (no OS is dependent on another partition or OS).

Windows may look like it treats partitions and drives the same, but it doesn't.

 

If I am setting up two XP installs on separate partitions on a single disk, can I simply do a fresh install on one partition (let's call it C and then mirror that install to the second partition D: Then I would use DD to hide one of the two identical partitions. On startup, XP should boot to the unhidden partition, ignoring the hidden one, correct?

Or are specific hidden boot files created which would confuse this scenario?

 

The general procedure is to do the following:

• Create your partitions (this is best done from the DD CD to avoid drive letter problems in Windows).
• Set the first OS partition Active and Hide the others.
• Install the first OS.

To install an additional OS:

• Unhide the partition for the new OS.
• Set the new OS partition Active.
• Hide all other OS partitions.
• Install the OS.

By doing this, you can select which OS will boot by which partition is Active. Make sure you hide any other OS partitions to keep them isolated.

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You can install XP 1 and then image it or copy it with DD to another partition. If you do this, I would recommend you use the TI/DD CD instead of doing it from Windows so Windows doesn't cause problems because of the duplication (drive letter problems, etc.).

Booting would be the same: Make sure the partition you want to boot is Active and the others are Hidden.

With XP, you may need to edit the boot.ini file to point to the correct partition. If you use TI, it should make any necessary changes. If you use DD, you'll need to make the change yourself.

 

Thanks, this is very, very helpful. I was planning to do all this from the TI/DD CD, recognizing that once you are booted into Windows, things can get out of control. A couple of questions:

1) Are you saying that if I use TI (instead of DD) to mirror C: to D:, then there will be no need to edit the boot.ini file? (The only other operation in this setup is to hide/unhide partitions, and this is done in DD, not TI.)

2) Can the hiding/unhiding be done from whichever Windows partition is booted up, or should it be done from the TI/DD CD "shell" (i.e. outside of Windows running)?

3) Based on a scenario of hiding partitions except for the one boot partition, what is the purpose of OSS or some other software boot manager? If you use a software boot manager, do you still have to hide/unhide partitions?

4) I did read your monograph on Vista's boot manager, and other posts. Why can't I use the same dual-XP scenario as above with a Vista-XP scenario? To wit: create 2 partitions, then hide one. Install Vista on one partition, then hide it. Install XP on the other partition. Then boot from whichever partition is not hidden.

Would be easier if all this hiding/unhiding/boot partition selection could be managed from a turnkey software solution. I tried to use OSS but ran into issues so switching to a non-boot manager approach.

 

TI will normally make corrections to the boot.ini file for XP (TI 10 or later) or the BCD (TI 11 or later) for for Vista when you restore it so (in most cases) you shouldn't need to make any changes. However, if you do need to edit the boot.ini file, you can boot to the DD CD, Explore the partition and edit it.

This can't be done from Windows. You need to do it manually using the DD CD or install a boot manager to handle it.

Boot managers will take care of the settings for each OS you boot. This includes which partition is Active, which are Hidden, etc. That's the purpose of using a boot manager -- to make it easier.

You can. When installed this way (isolated from each other), the Windows OS doesn't matter. Don't forget you need to set the booting OS's partition as Active too.

Using a boot manager is the easiest way to manage a multi-boot computer. If you're just booting a couple (XP & Vista or XP & XP, for example) and don't switch between them very often, you can get by without using a boot manager.

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If you want to use separate drives, you can. However, if you use this approach, it's still best to hide the OS partitions from each other (my opinion, at least). By using different physical drives, you can select which OS to boot by setting that drive as the booting drive in the BIOS. If your computer has a Boot Menu key (F11, for example), this is even easier because you can switch drives without needing to enter the BIOS.

Be aware that for best results when using different physical drives, install each OS with the other drive disconnected (recommended) or with all partitions hidden. This will help avoid any Windows boot manager entanglements.

 

Just to confirm, you are stating that TI makes changes to boot.ini during the mirroring process, but DD doesn't/can't do this?

Well, then, why aren't we all just using OSS to manage this, no tweaking hidden/unhidden, sustem boot menus or BIOS boot drive sequences? It sounds like it doesn't work all the time, from all the posts here.

I partition/format all drives as primary & active, even data drives. Never had a problem. I have no logical drives in multi-drive rigs. Issue?

Drives are cheap and I have plenty plus the case space and PSUs to run them. All my mobos offer a Boot Menu option. And as with multi installs of XP on several partitions on a single drive, I could likewise install XP (or Vista) on one physical drive, then use the TI CD to mirror that install to a second physical drive, then hide one of the partitions. At that point, would not the system BIOS simply boot to the first available boot drive, i.e. whichever one is unhidden? Seems like there's no need to use the Boot Menu or tweak the BIOS. Only one bootable drive is available, and the system should boot from that. Guess I will have to try it.

 

As far as I know, DD doesn't change any booting files when you copy a partition. TI will adjust, if necessary, so the restored partition can boot.

OSS has its bugs and quirks, as do most programs. If OSS doesn't work correctly for you, there are other boot managers available.

You can only have one Active Primary partition on a drive. For a Windows OS, if you use the entire drive for one partition, it will normally be Active Primary.

You can definately try this. Just keep in mind that if you don't want to bother with needing to hide the partitions/drives from each other, there may be problems with booting or drive letter assignments. Usually, if you do separate installs instead of a "duplicate" restore, this isn't a problem. It may also not be a problem if the partitions/drives are different sizes. Also, if you let XP see your Vista partition, you'll lose any System Restore Points you have in Vista.

You can't use the BIOS to just boot whichever partition isn't hidden. The BIOS will boot the first hard drive in the boot order list or the drive you select from the Boot Menu. If you're going to do it this way, you might as well not bother with hiding the partitions from each other. Just make sure when you do the installations that only one drive is connected.

It sounds like you have some drives to play around with. I'd suggest you do just that and see what works and what problems (if any) you run into.

 

Well aware of this issue. You really have to make sure you hide drives or partitions. If you mirror XP from C: to D: and then forget to hide C: when you boot from D:, it will work, but the system is going to save settings, registry, documents, etc. to C: A mess. Been there. Not sure what kinda problems occur if you leave C: unhidden, then do a fresh install of XP to D:, then boot from D: Will C: be impacted? Need to try that.

I routinely turn off System Restore in XP simply because I have found it to be a flawed function. Half the time it didn't work to restore a system to a prior iteration. Plus it sucks CPU and drive bandwidth while it is creating restore points, slowing things down. I have not played with System Restore in Vista. Maybe MS fixed it. Good to know that XP can hose Vista Restore Points if the Vista partition is not hidden.

My form of System Restore is called backup mirrors and regular backups, including using Carbonite. If I want to try something out that is iffy, that's why I want to have a separate system with multiple installs of XP. If some app doesn't work quite right or is bogus or infected, I wipe the install with a clean TI backup or a mirror from another partition. It's the only way to be sure.

I used to keep all my drives (boot and data) in external drive trays, and just pop in whatever boot drive was desired. With new builds, I still use one SATA drive tray and one IDE drive tray -- for data only. I have decided to install boot drives in the system tower. They run cooler in the tower (bigger fans, more circulation), and I find that I just don't need to change boot drives as much as I thought. That's why I'm dinking with multi-boot setups. Even with an eSata bracket that supplies both power and connectivity to a drive on an ad hoc basis, for me it seems easier to hide/unhide drives/partitions and select from a Boot Menu, rather than searching through a stack of drives for the one to boot. Only time will tell.