small installable linux with ext4 support as standalone grub

[M.R.Hadian]

Hi
i have a system with some linux distroes that i use for testing different capabilities of distroes. i need to have a standalone grub to boot every of these linux distroes. on other word, i want to have an installed small linux on a partition to be used as a grub only. since some of the distroes are in ext4 partition, the grub should support the ext4 filesystem too.
what is your suggestion?

[Lostfarmer]

You could make a small ext2 partition of arould 1Meg, that should handle all the grub files. No other files placed on this partition.

It will depend on if you prefer to use grub legacy or grub 2 on the next step to install grub to the MBR using grub on the small partition. You must be careful with grub install command or you will use the wrong grub files. I can help with the command once you say which grub version you want.

I would select to use grub legacy due to 'my oppion' it is easyer to use and update menu.lst then grub.cfg.

I have only used 2 different linux's so not 100% sure if below will work on all. There are other ways to do it, I have used both grub versions. The grub 2 version was downloaded from source and installed , that does make a little differnce than if it was installed for the repository for the linux in use.

When you install the test linux's , select to install grub to its root partition. Add entrie to boot menu of small partition to chainload to the test linux partition, that way it will not matter what linux file system is in use. If lets say you are booting OpenSuse on SDA3 and change it to Simpy Mepis , it will boot with no menu.lst modifications if chainload option is used.

[M.R.Hadian]

I want to use grub 1 . as you notes, i prefer to ask every linux to install its own grub on its root partition. if i can install that grub i can chainload to every linux's installed. So, i am so eager to have your instruction for installing grub in that partition.
please note that this grub should be able to chainload to a linux inxtalled on ext4. ( i had centos as main grub but it could not boot my linux installed on ext4).

[Lostfarmer]

( i had centos as main grub but it could not boot my linux installed on ext4).

If you are chainloading , there should be no problem, that is the same way XP/7 is booted. With chainloading the first sector of selected partition is read and the file system should not matter, I can not verify as only have ext3 partitions.

If you want a dedicated boot partition using grub , you must boot system with a linux that also uses the same grub to run the needed grub install commands.

Below is for grub legacy version below 1.xx and dedicated partition is on sda1/(hd0,0), if hdd/partition is different change references. Will give basic not detailed how-to. Will assume grub stage1 will be installed into the MBR of same hdd. I am doing this from memory so errors may be made.

1) Make needed folders on sda1 /boot/grub/
2) copy all grub files from booted linux /boot/grub/* to folder step #1
3) enter a root terminal
4) type in grub >enter
5) should now have the grub prompt grub >
6) setup (hd0) (hd0,0)
should display some info with success ,with luck or give an error.

command on step #6:
the (hd0) is location to install grub , "MBR of first hdd"
the (hd0,0) is loacation of the grub files to use for the install ,+ the menu.lst and splash screen that will be used dueing boot.

7) edit sda1/boot/grub/menu.lst to look similar to : being sure to use correct (hdx,x) numbers '(hddrive#,partition#)'.

title linux on hda5/sda5
rootnoverify (hd0,4)
chainloader +1

title linux on hda2/sda2
rootnoverify (hd0,1)
chainloader +1

:note some grub legacy's have been modify to directly boot ext4 partitions but I do not know which ones.