Rammjet Posted July 28, 2006 Share Posted July 28, 2006 There are a lot of people who experience a b0 error on their first boot up after installation. Or the bootloader immediately takes them back to the Windows installation (on dual boot). These people probably forgot to set the MacOSX partition "Active" A common mantra provided here to newbies for setting up for installation is: Make the partition Primary Make the partition ID=AF (signifies an HFS partition) Make the partition Active There is a built-in Unix utility in MacOSX that can be used to set your partition "Active". It is called Fdisk Setting Your Partition "Active" Using Fdisk Words in bold below are things you must type (followed by Enter). 1. Boot your Mac OS X install dvd 2. Once the installer is running, go to the Utilities menu and open Terminal 3. Determine which disk your MacOSX partition is on Type diskutil list Verify which disk number holds your partition (disk 0 , disk 1 , etc.) 4. Start using Fdisk Assuming the MacOSX disk is the first disk ("disk0"), then type fdisk -e /dev/rdisk0 <== use "rdisk" with your disk number here !! Ignore the error "fdisk: could not open MBR file ..." 5. Determine which partition for MacOSX needs to be set "Active" Type p Verify which partition is for MacOSX (1, 2, 3, etc.) 6. Set the partition "Active" Assuming it is partition 1, then type f 1 <== use your partition number here !! 7. Save and exit Type write Type y (yes you are sure) Type exit (to quit) 8. Remove the install DVD and reboot 3 Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/ Share on other sites More sharing options...
Chevelle Posted July 28, 2006 Share Posted July 28, 2006 Or for the people that don't like to wait for the MacOSX disc to boot. You can just use a Win98 Boot Disk. Run FDISK and set partition active. Just My . Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-151350 Share on other sites More sharing options...
Rammjet Posted July 28, 2006 Author Share Posted July 28, 2006 My intent is to allow the user to get to Fdisk with tools I know he has on hand. So he doesn't have to search for anything else or download anything else. Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-151357 Share on other sites More sharing options...
koolaidman23 Posted August 6, 2006 Share Posted August 6, 2006 My intent is to allow the user to get to Fdisk with tools I know he has on hand. So he doesn't have to search for anything else or download anything else. and this user thanks you!! Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-156716 Share on other sites More sharing options...
VirtualGuitarist Posted August 6, 2006 Share Posted August 6, 2006 Thank you very much Rammjet. I was looking for a simple solution like this. Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-156795 Share on other sites More sharing options...
fiap Posted August 9, 2006 Share Posted August 9, 2006 i'm having "sudo:command not found" , using 10.4.6 Jas PPF1 patch..... HELP!! Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-159982 Share on other sites More sharing options...
Rammjet Posted August 9, 2006 Author Share Posted August 9, 2006 Usually that means what you typed after the sudo command had a typo - it's not sudo it can't find, it can't find the command that sudo was supposed to execute. sudo(space)fdisk(space)-e(space)/dev/rdisk0 <- replace 0 if necessary Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-159990 Share on other sites More sharing options...
Quan Dang Dinh Posted August 11, 2006 Share Posted August 11, 2006 hi, dear fiap, at Mac OS X not exist sudo command, you can use: fdisk -e /dev/rdisk0 instead good luck!!! Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-161481 Share on other sites More sharing options...
Silthrim Posted August 19, 2006 Share Posted August 19, 2006 thank you so much, this really helped me out! Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-169844 Share on other sites More sharing options...
OSX86tester Posted August 24, 2006 Share Posted August 24, 2006 strange i did this twice i am still not able to boot osx completey by itself. i either need an install disk in the drive for 2 seconds or the ubcd. i have no idea whats going on. I still havent found the answer to my problem. do i need darwin or something to jumpstart the boot process? otherwise if i reboot its just a black screen with a blinking underscore Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-173395 Share on other sites More sharing options...
xandiztxu Posted August 28, 2006 Share Posted August 28, 2006 If I already installed JAS 10.4.6 what should I do Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-176378 Share on other sites More sharing options...
appleshark Posted August 30, 2006 Share Posted August 30, 2006 Usually that means what you typed after the sudo command had a typo - it's not sudo it can't find, it can't find the command that sudo was supposed to execute. sudo(space)fdisk(space)-e(space)/dev/rdisk0 <- replace 0 if necessary Hi, i am trying to make my disk or partition active so OSX will boot. I typed in "diskutil list" and it returned me with "/dev/disk0, /dev/disk1, /dev/disk2, etc." how is it that yours has a "r" in front of "disk." Also when i typed the sudo command it also said "command not found." I tried putting the "r" in where you had it, but it didn't make a difference. Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-177552 Share on other sites More sharing options...
Rammjet Posted August 30, 2006 Author Share Posted August 30, 2006 Hi, i am trying to make my disk or partition active so OSX will boot. I typed in "diskutil list" and it returned me with "/dev/disk0, /dev/disk1, /dev/disk2, etc." how is it that yours has a "r" in front of "disk." Also when i typed the sudo command it also said "command not found." I tried putting the "r" in where you had it, but it didn't make a difference. The intent of the "diskutil list" command is to determine the id number of your hard drive (0, 1, 2, etc). Then you append that number to "sudo fdisk -e /dev/rdisk#" where "#" is the number you determined from "diskutil list" If the command isn't found, you have a typo somewhere. Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-177734 Share on other sites More sharing options...
sdelano Posted September 10, 2006 Share Posted September 10, 2006 I can't figure out the partition I need to make active after entering "p" into the terminal...which one is it from this screenshot? Thanks Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-185130 Share on other sites More sharing options...
Rammjet Posted September 10, 2006 Author Share Posted September 10, 2006 Off hand, I would say 2. However, I would be more comfortable if I could see all of the output from the "diskutil list" command so I could be sure how you set up your drive. Half of it has scrolled off the top. Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-185143 Share on other sites More sharing options...
sdelano Posted September 10, 2006 Share Posted September 10, 2006 It was 2, and that just plain didn't work for some reason... I just had a flashing undersore (what it does when searching for bootable drives) So I then set it to 1 and xp booted for the first time in half a week so I was kinda stoked. Then I just said f*** it and did the Chain0 method. Now it works...only gripe I have about the Chain0 method is that I have to select OS X then pres enter at the darwin boot screen and select OSX again manually otherwise it doesnt work...anybody know anything about that? Here is my com.apple.boot.plist: <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>Kernel</key> <string>mach_kernel</string> <key>Kernel Flags</key> <string></string> <key>Boot Graphics</key> <string>Yes</string> <key>Graphics Mode</key> <string>1280x1024x32</string> <key>Timeout</key> <string>10</string> </dict> </plist> Thanks Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-185211 Share on other sites More sharing options...
Will Ryan Posted September 15, 2006 Share Posted September 15, 2006 Hmmm....it doesn't seem to be working. Here's a screenshot: http://img217.imageshack.us/img217/2919/asdfasddx3.jpg I have a feeling I'm doing some of the stuff wrong. Everything I wrote is in Red. Also, after I type "write," it says writing blakhg something, then nothing happens. Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-189028 Share on other sites More sharing options...
Rammjet Posted September 15, 2006 Author Share Posted September 15, 2006 Everything that you typed in fdisk looks correct and the responses from fdisk look correct. What doesn't look right is that under "diskutil list", the 2nd partition says it is NTFS. If that is the OSX partition, it shouldn't say that. Did you format the OSX partition in Disk Utility during the installation? Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-189038 Share on other sites More sharing options...
speakerwizard Posted October 1, 2006 Share Posted October 1, 2006 Heya Guys, so, im still quite new here and found this thread that appered to be the answer to my problem, but im not entirely sure what im doing haha, there so many different disk numbers when i do the diskutil list, im not sure what to pick, and when i picked what i thought was right it didnt let me do it, heres the terminal window, if somebody could give me a lil' help, thanks http://www.flickr.com/photos/64403079@N00/257203325/ Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-199343 Share on other sites More sharing options...
Rammjet Posted October 1, 2006 Author Share Posted October 1, 2006 /dev/disk0 contains your HFS+ partition /dev/disk1 is your installation DVD use: fdisk -e /dev/rdisk0 then set partition 1 to active (f 1) Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-199372 Share on other sites More sharing options...
speakerwizard Posted October 1, 2006 Share Posted October 1, 2006 Hi, thanks Rammjet but when i type "fdisk -e /dev/rdisk0" i get permission denied, do you know why this is? thanks in advance Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-199382 Share on other sites More sharing options...
Rammjet Posted October 1, 2006 Author Share Posted October 1, 2006 Try "sudo fdisk -e /dev/rdisk0" and give your password when asked. If you are actually booted from the install DVD as the guide says, it shouldn't need permissions. Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-199388 Share on other sites More sharing options...
speakerwizard Posted October 1, 2006 Share Posted October 1, 2006 Hi Thank you soo much rammjet, it was booting from HD, but only with install disk in the drive, but that sudo thing worked a treat. Helpful guys like you are what make the net great! Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-199429 Share on other sites More sharing options...
eyemac Posted October 4, 2006 Share Posted October 4, 2006 I tried cloning a disk with carboncopy cloner but when I then attempted to start from the cloned disk, it would not boot (got an error on verbose indicating still waiting for root). I assume this is because the disk is not set correctly. (MBR not set to active?) Is this correct? Can it be fixed with Fdisk as described previously by setting the partition to active? I would like to be able to clone an OSX86 disk so that I can upgrade to a larger capacity drive.. and I can do this with my PPC macs without problems. Thanks. SG Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-202075 Share on other sites More sharing options...
Rammjet Posted October 4, 2006 Author Share Posted October 4, 2006 No, it's not a matter of setting the partition active. If the clone is going to be the only thing on the drive, then the drive has to be prepared correctly. http://forum.insanelymac.com/index.php?s=&...st&p=198548 Link to comment https://www.insanelymac.com/forum/topic/22844-how-to-setting-your-partition-active-using-fdisk-in-macosx/#findComment-202132 Share on other sites More sharing options...
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