|
Softpanorama |
May the source be with you, but remember the KISS principle ;-)
|
| Reference | Software RAID | |||||
| Linux Swap filesystem | Linux filesystems | Ext2/Ext3 File System | ||||
| Linux Multipath | udev | Labeling the partition | Loopback filesystem | How To Manage Your Disk By UUID | Humor | Etc |
This topic includes the following subtopics:
Rule 1. Make a full backup of the disk or at least the most
important files
Better to have a full backup and not need it than not have a backup and
find you needed it. Please remember that files destroyed during
repartitioning are very difficult to recover -- backup time is really
tiny in comparison with efforts you will need in case something go
wrong...
Rule 2. Read the instructions
Errors are very costly. Do not try to operate intuitively. Even if you've done it before, it pays to
review the documentation. And if you've never done it before, or do it
rarely, read those instructions closely.
Rule 3. Follow the instructions! Do not improvise during repartitioning
|
|||||||
Darik's Boot and Nuke ("DBAN") is a self-contained boot disk that securely wipes the hard disks of most computers. DBAN will automatically and completely delete the contents of any hard disk that it can detect, which makes it an appropriate utility for bulk or emergency data destruction.
Disk /dev/dm-0 doesn't contain a valid partition table
This has been very helpful to me. I found this thread by Goggle on
dm-0 because I also got the no partition table error message.Here is what I think:
When the programs fdisk and sfdisk are run with the option -l and no argument, e.g.
# /sbin/fdisk -lthey look for all devices that can have cylinders, heads, sectors, etc.
If they find such a device, they output that information to standard
output and they output the partition table to standard output. If there is
no partition table, they have an error message (also standard output).
One can see this by piping to 'less', e.g.
# /sbin/fdisk -l | less
/dev/dm-0 ... /dev/dm3 on my fedora C5 system seem to be device mappers
associated with LVM.RAID might also require device mappers.
If you run suse 10.3 yast > system > partitioner show you with part is used by suse ,and with part is still unused.
I know if you startup the partitioner it gives you a warning but as long as do not change any think every is oke
If according to the partitioner sdb is unused then you can do every think with it for instance to create a second primary partition for a second OS If you put GRUB of the second OS in the second primary partition Suse is still there
and must it be possible to change suse boot loader in that way that she also load the second OS
BUt there are more ways to do what you like to do
all the best
For creating ext3 and xfs file systems, mkfs.ext3 and mkfs.xfs have
the -L option to specify the disk label that should be used. For
existing file systems, use e2label to label an ext2/ext3 file
system. And for xfs file systems, use xfs_admin. Both of these
commands can be used with the device to display the existing disk
label.Examples of initializing new file systems with a label:
mkfs.ext3 -L ROOT /dev/sda1 mkfs.xfs -L BIGRAID /dev/sdeExamples of e2label and xfs_admin for existing files systems:
e2label /dev/sda1 PRIMARY_ROOT e2label /dev/sda1 xfs_admin -L DATA1 /dev/sdf xfs_admin /dev/sdflabeling swap devices
You can label a swap device by using the mkswap -L label option.
mkswap -L SWAP0 /dev/sdb5Alternative / by-id
Alternatively, you can use the udev by-id specification (look
in /dev/disk/by-id). The ID paths are usually pretty long
and less meaningful, but they are device specific and won't
change as a result of hardware changes. It's probably best to
use a disk label as above. However, for vfat/fat file systems
disk labels are not available so the by-id specification
should be used./dev/disk/by-id/scsi-3500000e01632b7d0-part2 swap swap defaults 0 0Examples of Use
Finally, the following are examples of using disk labels in
two key system files, fstab and grub.conf.Example of /etc/fstab with disk labels:
LABEL=ROOT / ext3 defaults 1 1 LABEL=BOOT /boot ext3 defaults 1 2 LABEL=SWAP swap swap defaults 0 0 LABEL=HOME /home ext3 nosuid,auto 1 2Example of /boot/grub/grub.conf with disk labels:
title astrid CentOS primary system root (hd0,0) kernel (hd0,0)/vmlinuz ro root=LABEL=ASTRID_ROOT0 rhgb quiet initrd (hd0,0)/initrd-astrid.imgSummary
Linux systems support disk labels via the udev device manager. Using disk
labels avoids hard coding device names which can change if there's a
change in the hardware configuration (disk added/removed). This will result
in a more robust system.
LinuxPlanetThe Linux kernel is a restless beast, and must continally evolve and change. Especially in ways that mystify us poor end lusers. A recent wrinkle, as of kernel version 2.6.20, is changing the /dev names for ATA devices, so that all ATA and SCSI devices are named /dev/sd*. This is a result of using the shiny new libata subsystem. In the olden days PATA (also called IDE) hard drives and ATAPI devices (CD/DVD, tape drives) were /dev/hd*, and SCSI and SATA devices were /dev/sd*.
However, not all Linux distributions default to using libata. *buntu Feisty and Gutsy are all over the map; some versions of them use the new naming convention, some don't, and I haven't figured out which ones, or why. You can see how your own system handles these names with a couple of simple commands. This example from Kubuntu Gutsy shows the old style:
$ ls /dev|grep '[s|h]d[a-z]' hda hda1 hda2 hdc hdd sda sda1 sda2 $ mount|grep ^'/dev' /dev/hda1 on / type ext3 (rw,errors=remount-ro) /dev/sda1 on /home type ext3 (rw) /dev/sda2 on /media/sda2 type ext3 (rw) /dev/hda2 on /var type ext3 (rw)The first command shows all the ATA and SCSI devices detected by your kernel. The second command shows which ones are mounted. On this system there is one PATA hard disk with two partitions (hda), two CD/DVD drives (hdc, hdd), and one SATA disk with two partitions (sda). When I boot into Fedora 8, which defaults to libata, it looks like this:
$ ls /dev|grep '[s|h]d[a-z]' sda sda1 sda2 sdb sdb1 sdb2Where are the two CD/DVD drives? These get /dev/sr* names under libata:$ ls /dev|grep sr sr0 sr1
InformIT Understanding Memory Technology Devices in Embedded Linux What's Flash Memory
Linux Device Drivers, 2nd Edition Chapter 1 An Introduction to Device Drivers
Using Disk Labels on Linux File Systems - BigAdmin - wikis.sun.com
Darik's Boot and Nuke ("DBAN") is a self-contained boot disk that securely wipes the hard disks of most computers. DBAN will automatically and completely delete the contents of any hard disk that it can detect, which makes it an appropriate utility for bulk or emergency data destruction.
Partitioning with fdisk redhat.com
fdisk - Wikipedia, the free encyclopedia
Fdisk Tutorial Removing and Creating Partitions Windows installation Tech-R
Copyright © 1996-2008 by Dr. Nikolai Bezroukov. www.softpanorama.org was created as a service to the UN Sustainable Development Networking Programme (SDNP) in the author free time. Submit comments This document is an industrial compilation designed and created exclusively for educational use and is placed under the copyright of the Open Content License(OPL). Original materials copyright belong to respective owners. Quotes are made for educational purposes only in compliance with the fair use doctrine.
Standard disclaimer: The statements, views and opinions presented on this web page are those of the author and are not endorsed by, nor do they necessarily reflect, the opinions of the author present and former employers, SDNP or any other organization the author may be associated with. We do not warrant the correctness of the information provided or its fitness for any purpose.
Last modified: December 25, 2008