Re: debianlive iso with xfce and clamav
Hi,
David Christensen wrote:
> > there are valid reasons for putting the rescue operating
> > system and the images on one large capacity device
rlharris@oplink.net wrote:
> 1. Would not that require the drive to be partitioned into an
> "installation" partition and a "debianlive" partion?
Yes. The partition for the disk based operating system has
to be added.
If you start with one of the isohybrid ISOs (e.g.
debian-8.2.0-amd64-netinst.iso) then put it on the stick as
described in
https://www.debian.org/CD/faq/#write-usb
After that your stick is a partitioned "hard disk".
$ /sbin/fdisk -lu /dev/sdc
Disk /dev/sdc: 1.9 GiB, 2004877312 bytes, 3915776 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x7714c637
Device Boot Start End Sectors Size Id Type
/dev/sdc1 * 0 505855 505856 247M 0 Empty
/dev/sdc2 3984 4815 832 416K ef EFI (FAT-12/16/32)
Now you need a partition editor which is willing to tolerate
- the fact that partition 2 lies inside partition 1
(/sbin/fdisk -l labels partition 1 as "Empty")
- the fact that there are both, a MBR partition table and a
GUID Partition Table (GPT).
By this editor you add partition number 3 and maybe number 4.
I will use MBR partition editor fdisk, but first zapp the GPT header
block in order to remove the ambiguity of partitioning.
The main header is at 512-block 1 (directly after MBR):
$ dd if=/dev/zero of=/dev/sdc bs=512 seek=1 count=1 conv=notrunc
The backup header is in the last 512-block of the ISO.
It will become part of the new partition and there is supposed
to be regarded as meaningless garbage.
Next would be a session with fdisk:
$ /sbin/fdisk /dev/sdc
with input
n
p
3
w
A total of 6 inputs, two of them empty lines.
I did this as normal user (after chmod g+w /dev/sdc).
So i have now to unplug the device and plug in again to force loading
of the partition table by the running Linux kernel.
Now i have /dev/sdc1, /dev/sdc2, dev/sdc3
$ /sbin/fdisk -l /dev/sdc
...
Device Boot Start End Sectors Size Id Type
/dev/sdc1 * 0 505855 505856 247M 0 Empty
/dev/sdc2 3984 4815 832 416K ef EFI (FAT-12/16/32)
/dev/sdc3 505856 3915775 3409920 1.6G 83 Linux
Let's try whether it still boots:
$ qemu-system-x86_64 -enable-kvm -m 512 -hda /dev/sdc
... Debian GNU/Linux installer boot menu ...
$ qemu-system-x86_64 -enable-kvm -m 512 -cdrom /dev/sdc
... Debian GNU/Linux installer boot menu ...
So now the stick is usable as Debian installation medium with
additional data vault. The adventure begins when you populate
that vault with a disk based operating system.
-----
One could decide to let GPT survive. But other than MBR
partitioning, GPT is clearly specified to not have overlapping
partitions.
I have a proposal pending to omit GPT from Debian ISOs and
to append the EFI boot partition _after_ the ISO partition.
Although this would waste the room of a duplicate EFI boot
image, it would make above use case more straightforward.
(Start fdisk and make partition. Basta.)
The price of 416 KiB can hardly be unaffordable.
> 2. And would it not be necessary that both partitions be bootable?
I understand that the "bootable" flag is a hint towards
bootloaders which partition to use by default or where to
look for a partition boot loader.
Neither ISOLINUX nor GRUB2 seem to care much about this.
> 3. Or is the "installation" partition ruined when the boot loader is
> installed?
It will be interesting to see what debian-installer does
to its own boot equipment when installing the boot loader
of the hard disk based system.
We have two boot loaders and their configurations:
ISOLINUX used for BIOS machines, GRUB2 used for EFI machines.
Only experiments will give insight.
Make a (sparse) installation, reboot, and look what choices you
get offered by the boot menu.
Have a nice day :)
Thomas
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