i have win7 at sda1 and buster at sda2
i install centos 6 at sda3, it can boot win7, can't see buster
i mean i can't boot buster now
is there some rescue image that can be written to bootable usb disk?
or do you know how to config centos 6 boot loader?
is buster's boot code installed at sda2 by default?