The other day I downloaded the liveDVD for i686, 2007.0. I burnt it and brought it home to a friend to install a computer. The problem I faced was when I was going to install on a networkless-computer. When it should copy the basefiles the installer (both the gtk and the console) jumped to libperl (package 50) and stopped there. One time I got errormessage about missing files on the destination so I took a look there and at the destination root there was only var/{tmp,lib},tmp and two sh-files. So here comes the real problem: I do not know if there is a fault in my image or in my burn, and there was no way for me to try that. The computer I was at had no installed network and no installed OS, the only computer I had access to was a windows-computer. And the only way I know how to check a Gentoo-disc is to do a md5sum check agains /dev/dvd but how do you do that in windows? The proposal: You could have a digest of the squashfs-image on the CD/DVD and a choice to make the liveCD/DVD check the squashfs-image against the digest at boottime. You do not need any fancy graphics like Ubuntu, just a OK or FAILED, wait for key and reboot is needed. I think a "checkdisc" would fit right in with "memtest86".
I'm not sure if this is feasible. Checksumming the squashfs image will only get you so far. Also, you can get a md5sum.exe for Windows.
A md5sum for windows would not have helped at all as there was no image on the computers where I was (no meaning as the computers where I was only had DVD-rom). And how do you check the DIGEST against an already burned disc in windows? Why would it only get me that far? If the DVD boots and there is a function to test if the important files are damaged (like the initrd, the kernel and the image), what else is needed?
Well, for one, if the CD booted, chances are nothing is corrupted. If the kernel/initramfs/squashfs were damaged, you would never make it to a prompt, at all. The only thing this would ensure is that you didn't download a compromised CD, but you can check that when you get the image. I don't really see a need here, or any functionality on top of what is already present. You can use md5sum from the booted CD to check the CD.
Please give me an answer on this: You are at a friend (or at shool or at whatever). You have one computer. No more no less. You have one LiveCD/DVD, no more no less. You have no internet-connection. The LiveCD/DVD boot fine. You start installing. Halfway throu the installation the installer hangs/errors out. How do you know if it is due to a faulty disc? There is no way of testing the disc with md5sum, since there is nothing to verify against on the disc (i.e. no file with checksums). There is no internet to get the md5sum from. There is no other computer to test the checksum of the CD/DVD on. If it was Ubuntu you reboot and choose to check the CD/DVD for errors. If it was Gentoo you could mount the CD/DVD from your live-system and test the squshfs-file for corruption. If you had a file with the checksum placed on the CD/DVD to test it agains... For me I had no background in Gnome (did not know the LiveCD/DVD had one until I reburned the LiveDVD) and the installation hanged when it said it was copying the libperl files. Other than that I could not see any problems with the disc. But it had saved me some hours of frustration if I had been able to in some way check the disc for errors. By the way: the image was aquired from a gentoo-mirror and checked with md5sum. And it worked well when it was reburned.
