Results 1 to 10 of 31

Thread: How to bypass the 4-partitions limit?

Hybrid View

  1. #1
    Join Date
    Jan 2008
    Beans
    18

    How to bypass the 4-partitions limit?

    Hello guys,
    I have got a MacBook with MacOS and Ubuntu 7.10 .
    Now, since I had problems with upgrade to 8.04, I'd like to separate home and root partitions, but I know that there is a limit of 4 partitions.
    I obviously have one partition for Efi, one partition for MacOS, one for Linux and one for swap.
    Now, is there a way for bypassing this limit?

    Thanks for your replies and forgive my bad english.

    Marcello.

  2. #2
    Join Date
    Feb 2007
    Beans
    2,339
    Distro
    Ubuntu 10.04 Lucid Lynx

    Re: How to bypass the 4-partitions limit?

    Create an extended partition, install the linux inside it. You can create a large number of logical partitions inside an extended partition (not sure the limit, but definitely more than you will ever need).

  3. #3
    Join Date
    Jan 2008
    Beans
    18

    Re: How to bypass the 4-partitions limit?

    Ok thanks!
    I have another little question, but I think that it's better to go OT here instead of opening another thread...
    Is my actual 32-bit home compatible with the 64-bit Ubuntu?

  4. #4
    Join Date
    Oct 2004
    Location
    Kingston, On
    Beans
    Hidden!

    Re: How to bypass the 4-partitions limit?

    Quote Originally Posted by MarcelloSav View Post
    Hello guys,
    I have got a MacBook with MacOS and Ubuntu 7.10 .
    Now, since I had problems with upgrade to 8.04, I'd like to separate home and root partitions, but I know that there is a limit of 4 partitions.
    Does a MacBook use a dos partition table with the 4 primary partition limit or does it use a mac partition table?

    Quote Originally Posted by MarcelloSav View Post
    Ok thanks!

    Is my actual 32-bit home compatible with the 64-bit Ubuntu?
    Since it's only configuration files, it should be.
    I lost a "z". Anyone seen it around here?

  5. #5
    Join Date
    Aug 2007
    Beans
    197

    Re: How to bypass the 4-partitions limit?

    I think Ubuntu installs the appropriate kernel automatically.

  6. #6
    Join Date
    Aug 2005
    Location
    Huntsville, AL, USA
    Beans
    7,526
    Distro
    Ubuntu

    Re: How to bypass the 4-partitions limit?

    Macs do not have the ability to create extended / logical partitions. They have a GPT formatted disc which actually allows for a very large number of partitions beyond 4 and does not require anything like that.

    However, the 4 partition "limit" is a limitation of the emulated MBR partition table and is always the first 4 partitions in your GPT. The problem is that you have incorrectly assumed that you can only use those first 4 partitions. It is only required that the partition containing the bootloader is installed in one of the first 4 partitions as well as windows, and any partitions that you want windows to be able to access. Other partitions have no issues being beyond #4. (This actually includes OSX itself.)

    basically... create your root partition as one of the first 4, and you can put the swap and home partitions wherever you like and they will work fine. (Once the kernel is loaded, Linux can access the GPT and see all the partitions on the disc.)

  7. #7
    Join Date
    Jan 2008
    Beans
    18

    Re: How to bypass the 4-partitions limit?

    So if I split the actual linux partition in two, my swap partition will be the last partition, #5, I will not have any kind of problem?

  8. #8
    Join Date
    Apr 2008
    Beans
    2

    Thumbs down Re: How to bypass the 4-partitions limit?

    I just want to share my experience (pardon my engrish). I got hint from many other site that most of it I cannot remember.

    I tried installing dual-boot osx and ubuntu, after a couple of osx re-install and more ubuntu re-install, I think I got partition layout that will survive the next ubuntu release re-install. I got 9 partition in total, I put the /boot partition in front of Mac OSX partition. I'm using MacBook 4.1 SantaRosa and Leopard

    This is what I did, your setup maybe different. ( Please don't follow this step, this is just a sharing, not a tutorial ) :
    • Boot using linux liveCD, I'm using GParted liveCD. OSX Disk Utility can't create anything smaller than 1GB
    • Delete macosx partition (partition 2, if the macbook is new or still in the original state), leave partition 1 (EFI partition, it's the FAT32 in the first partition) (OR you could just resize from OSX, I like clean install better)
    • Plan the partition layout; mine is:

      1. EFI --> it's already there (around 200 MB)
      2. /boot partition for ubuntu (mine is 100MB) (macbook is using GUID partition table, not MBR. EFI can only boot from the first 4 partition. Linux has support for GUID, as long as the kernel booted)
      3. MacOSX System partition (mine is 40GB)
      4. MacOSX Data partition (again, this is a GUID disk, there is no extended partition) (mine is 16GB)
      5. MacOSX and Ubuntu shared partition (mine is 40GB)
      6. Swap file for ubuntu (I got 4GB of ram, I create 4,5GB for this)
      7. / (root) (16 GB)
      8. /home (16 GB)
      9. /other (the rest)

    • create partition 2 - 9 from above AS AN EMPTY PARTITION
    • reboot using mac OSX install DVD, install Mac OS X (I'm using leopard) to the 1st partition (the 2nd partition (the 40GB partition) in gparted, the EFI partition is hidden in Mac OSX) , don't install what you don't need (I deselect printer driver and language)
    • Boot into OSX, using Disk Utility, format the 2nd (16 GB) as an Apple OSX partition (HFS+) journaled and the 3rd partition (40GB) as CaseSensitive, Non-Journaled (HFSX), and leave the rest unformated. (read this and this)
    • Update MacOSX and install rEFIt in MacOSX
    • Insert Ubuntu CD (I use alternate i386 CD and did command-line install) and reboot, Choose Linux CD from rEFIt menu
    • Install ubuntu as usual, using partition 2 as /boot, 7 as / (root), 8 as /home and 9 as /data. Don't forget to name the partition (it's different from label) . (I notice that the HFS partition created from OSX has around 132 MB of free-space between partitions. Anybody know why?)
    • After ubuntu installation has finish, restart and choose 'Start Partitioning Tool' from rEFIt menu, or you won't be able to boot to ubuntu. Sync GUID and MBR table. Every time you did something to a partition (format, delete, resize, etc), you have to resync again
    • Did whatever you used to do, from here on it's just the same as regular install


    I hope someone found an easier way to do this. I'm still tweaking my MacBook... trying to get the wireless working.

  9. #9
    Join Date
    Mar 2008
    Beans
    90

    Re: How to bypass the 4-partitions limit?

    Quote Originally Posted by cyberdork33 View Post

    However, the 4 partition "limit" is a limitation of the emulated MBR partition table and is always the first 4 partitions in your GPT.
    You can also manually edit the MBR partition table to use any subset of the GPT, but the first partition of MBR table has to be the 200M protected EFI partition, otherwise the GPT table will be erased upon next boot.

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •