I am wondering is it possible to install more than 4 Linux distributions with windowz in a single machine ?
I got this doubt since we can make only 4 primary partitions on any harddrive...
It is possible to install more than ten (10) Linux distributions all installed in logical partitions with windows on any of the three available primary partitions
. And multi-boot them by a single grub installed somewhere among the ten linuxes; there is no need to install grub or any bootloader for the remaining nine (9) linux distros, so long as grub controls the MBR, and it only needs to chainload the built-in ntloader of Windows. The limitation of grub to multi-boot systems theoretically depends only on the limit of the MBR, EBR (or MPBR) that holds record of partitions; it is not inherent in grub nor in linux.
Neither Linux nor Grub care about "Primary partition", only Windows (and Gate?s) are limited to that stupidity. I suppose if a new MBR convention holds 1,024 partition records then Grub can multi-boot scattered linux kernels about that number because grub merely passes the order based on its record and list.
One (1) primary partition is what a Windows needs; with two (2) primary partitions Windows is happy to have one extra; with three (3) primary partitions, well, Linux doesn't need any of them!
Hope this helps.