I use sysrescuecd (http://www.sysresccd.org/) to make a new drive bootable. There are two ways to get a bootable disk with sysrescuecd.
One way is to use a special boot mode where sysrescue starts its own kernel to a system on the hard disk. Once booted you can just use 'grub-install /dev/sda' to install grub on the boot drive. I run software raid1 so I do this for both drives just in case I need to boot from sdb. A second way is to start sysrescuecd normally and mount the root file system to a directory. Make a directory say x and mount the root filesystem on it. Run these three commands: "mount --bind /dev x/dev" and "mount --bind /proc x/proc" and "mount --bind /sys x/sys". Then run "chroot x /bin/bash" to get a command prompt running off of your root file system with the dev, proc and sys populated correctly. Now you can run the grub install command and hopefully get a bootable drive. The first method works the best since sometimes grub gets confused in the chroot environment and cant find the hard drive you want to install it on. *...Bob* On 08/13/2014 11:27 AM, Martin G. McCormick wrote: > AW writes: >> 1. As far as I know, it's not possible to simply copy a working /dev tree. >> These are special files which are generated with the mknod utility. >> >> 2. Booting a computer is fairly complex. Everything needs to be at a >> specific >> location on the drive, needs to occupy the appropriate sectors - which >> vary in >> precise size depending on the drive geometry as well as the partitioning. >> And >> everything needs to appropriately connected together. >> >> 3. dd copies at the bit level. It's a low level utility. And that's why >> it >> works, while the high level rsync or cp utility will not. > This certainly makes sense to me but it has some rather > interesting disaster recovery implications. In this case, I am > just going to a newer and slightly larger boot drive and I am > lucky to have both the actual hard drive and a thumb drive copy > of that drive to experiment with. The thumb drive copy is also a > dd clone of the original hard drive and is obviously good > because it was what I used to make the new boot drive. If one > was having a bad day and their boot drive made a horrible noise > and blew out a cloud of aluminum and iron oxide dust as the > consequence of the meeting of a read/write head and the surface > of a platter, they have no options save for recycling of the > materials in the old drive. If they want to restore their old > system, they must be able to restore the boot drive before > applying their backup media whatever that happens to be. Chances > are very good that the new boot drive will be larger or > different in some way from the old one. > I am not disagreeing with what you said, but it sounds > like it could be a lot of trouble to restore that system. > > Martin > >
