Tuesday, May 6, 2008

Time Machine over Network Share

Here's what I did after reading several articles about this:

Open Terminal:

defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1

Connect to your network drive and save your password
Open Time Machine Preferences:
Select your Volume
Click Backup Now or wait for it to start.
Look on your volume and you will see a file called:
machinename_3493951911.sparsebundle or something similar
copy the first part not including sparsebundle
Wait for time machine to fail :-(
Open Disk Utility and click New Image
Paste in the name you copied and choose Desktop as the location. Change the type to sparsebundle. Give it a reasonable size and click create.

Unmount it and copy this file to your network drive. it should be about 80MB. Now go back to time machine preferences and reselect your network share. Click backup now and you are good to go!

Wednesday, February 27, 2008

Pie Charts Lie

Do these two charts appear to even remotely depict the same information? Supposedly they do. Is it just some sort of optical illusion?

"Almost there, buddy!"

"You might as well switch majors."

Thursday, January 17, 2008

Apple's Bootcamp bungles GPT specification

Ever wonder how Bootcamp works? Well, Apple has basically messed up the GUID partitioning standard to make it work with Windows, even though they could have just stuck with MBR and kept things simple. It is a horrible, horrible kludge. We finally figured out what this guy already found; partitioning and imaging a Macintosh is a real bastard, but possible. And no, Bombich's software (although pretty cool), just doesn't cut it when you already have a PC solution (Altiris Deployment) and a Mac solution (Xserve+NetInstall).

The GUID specification calls for a "protective MBR" with exactly ONE partition (with an ID of 0xEE). No matter how many partitions you create in the GUID table, there should only be ONE partition in the MBR table. ONE!

What Apple has done is make a hybrid GPT/MBR. In this case, "hybrid" is synonymous with "bastardized". Any partition you create (with apple tools) in the GUID table gets copied to the MBR table. This is why when you install bootcamp, you CANNOT remove the partition and recreate it; the geometry would not match what is in the GUID table. Once the two tables are out of sync, it's a real bastard to fix. ReFIT has a program called gptsync that will sync one way; GTP to MBR... but there is no reversal of that.

The really funny part is Apple's Tech Note from 2006 (probably just before BootCamp). They describe the Protective MBR as "a single partition entry (of type 0xEE) that covers the entire area of the disk used by GPT structures and partitions." A single parition? A Bootcamp Mac has three!

Furthermore, Apple mentions "Specifically, if block 0 contains an MBR with more than one partition entry, or a single partition entry whose OSType is not 0xEE, it is not a compliant GPT disk, and manipulating the GPT may cause dangerous inconsistencies between it and the legacy MBR."

and they follow that with a:

WARNING: Failure to comply with this recommendation may result in the loss of user data.

So there you have it... Apple's GPT support is completely laughable and confusing as hell. They completely violate their own recommendations not to mention the specs.

Ironically, I can use Apple's DiskUtility to format a Leopard Mac with good old MBR and 2 partitions. I can restore a Windows XP image (via RapiDeploy) and a Mac image (via netinstall) to these partitions, and THEY ARE BOTH BOOTABLE just FINE. The caveat is, you can only boot from EFI (holding the option key). Once you're in Mac OS or Windows, NONE of your disks appear in the startup disk preference pane (you can't even select the disk you are booted to). It's kinda sad when EFI is smarter than your proper OS...

Don't get me wrong; EFI and GPT are totally awesome technologies-- I just hope we can stick to the standards. This means Microsoft: Get on the ball and support EFI and GPT for Windows XP and Vista. And to Apple: Why don't you stick with MBR for dual-boot Macs? You only support 2 usable partitions anyway!