4 partitions limit on macbook

[felixdv]

Hi

I'm planning to buy a macbook for working on my thesis about linux server virtualization. It has nice design, not too expensive, the core2duo cpu is nice for hardware virtualization, and I needed a relatively lightweight and small laptop anyway.

The virtualization setup I need for my tests need multiple partitions. Now I have read that there's currently a 4 partition limit on the macbook, where 2 partitions allready would be taken by the EFI partitioning scheme and OSX. That leaves me with 2 usable partitions for my linux setup, which is in fact not enough.

Is there work in progress to enable more than 4 partitions (With a GTP-only setup, probably)? Or at least is it possible that I can have 2 linux setups on the 2 free partitions, as I don't need windows.

If not, any suggestions for a comparable (specs, size, weight and price) laptop with good linux support that would suit my needs for virtualization testing?

Thanks in advance!

[jwillis]

I'm currently running on a mini mac with 2 Linux partitions running GRUB in seperate partitions to get the native RHEL5 and SLES10 bootloaders

Number Start End Size File system Name Flags
1 20.5kB 210MB 210MB fat32 EFI system partition boot
2 210MB 39.9GB 39.7GB hfs+ Customer
3 39.9GB 40.0GB 105MB ext3 boot RHEL
4 40.0GB 40.1GB 78.4MB ext3 boot SLES
5 40.1GB 55.8GB 15.7GB lvm RHEL
6 55.8GB 71.6GB 15.7GB lvm SLES
7 71.6GB 72.6GB 1049MB linux-swap

The key I believe is to use Parts 3 and 4 as the /boot parts for RHEL and SLES respectively. I used LVM for Parts 5 and 6 in case I wanted to append to them later with something like a USB or Firewire drive, or add any unused space left on the drive. LVM is wonderful for knitting together parts and drives to extend logical partitions.

I should mention this works because both RHEL and SLES support GPT natively once its booted.. any reasonably modern Linux distro will.. just be careful of some of the older vintages.. they grow better with age.. "but as an uncle once said.. nothing wrong with progress.. I just think it went on too long.." If you want to use older Linuxes.. dump the entire thing into one PART per distro.

I never successfully got SLES to run with Reiser.. but I think it is possible, I just didn't understand what I was doing the first time.

The real reason for the limit "I think" is that the Legacy MBR emulation only supports Primary Partitions, no Extended partitions. So when you sync the GPT table to the MBR and boot into legacy BIOS boot mode (to get the accelerated ATI video driver support available in Linux or whatever) you choose to only support Primary Parts.

Since the Mac Mini has a Core2 Duo, Xen works great after you have one Linux Xen system to install other stuff like Win2003 or XP, but there was an acpi trick I had to learn there.

I'm trying to get MacOSX to install in an HVM, but currently have the infamous unable to boot from CDROM 0004 error, I have not tried the VMware flatten image with Qemu thing yet.. but hoping. It would be nice to have a hypervisor under MacOSX.

Only thing about rEFIt I could hope is that someone gets the remote to be used as a selector.. then I could get a Bluetooth keyboard and be happy.

Hadn't thought on it too much but seems you could use one GRUB to boot another in an infinite list of chains on GPT parts, as long as the Linux in a GPT part supports GPT it can find its partitions and mount them. The important part is the head of the boot chain needs to be in one of those special PART3 or 4 partitions supported by legacy Bios boot.

:)