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31

This is a limitation imposed by having a very old BIOS and bootloader rather than Linux itself. The BIOS would only be able to access the first 1024 cylinders of the disk (see here for more information on what cylinders/heads/sectors are). This limitation would extend to bootloaders which, due to their simple nature, would not have their own disk drivers and ...


20

Another reason beside the mentioned BIOS problem is that a separate /boot partition allows the use of a file system for the / volume which the boot loader does not understand (without being limited to block list loading like with lilo).


18

The history /boot contains files that aren't used by the operating system, but by its bootloader. You'll find both files of the bootloader itself (like /boot/grub/* for Grub) and the Linux kernel (/boot/vmlinuz*) and often an associated initrd or initramfs. On a PC with legacy BIOS (as opposed to the newer UEFI found on most recent computers), the software ...


14

BOOTING IS HARD Booting... well... it really is the hardest part. Every time a computer boots it basically meets itself anew. It acquaints itself with its various parts, and for each one it meets it gains capability. But it has to pull itself up by its own bootstraps, so to speak, from square one every time. When designing a boot process the trick is to ...


9

LVM is not overkill if you have 17 partitions. (IMHO) As for the partition limit, it just happens to be the default. Probably no one expected that many partitions on a device that used to have only a few megs. /usr/src/linux/Documentation/devices.txt: 179 block MMC block devices 0 = /dev/mmcblk0 First SD/MMC card ...


8

You can't convert, but can reformat the partition. Boot into Ubuntu or from a live CD and format the partition from there. Be careful not to format the wrong partition. mkfs.ext3 /dev/hdx1


7

That there is a /boot directory is historically determined and from there "fixed" in the Filesystem Hierarchy Standard. Having such a standard allows programs (and sysadmins) to expect certain files at certain locations. In this case the files associated with the boot process. Having a /boot partition at the beginning of a disc made sense for older BIOS'es ...


7

Another approach is with findmnt: findmnt /dev/sda4 ...to get mountpoint from dev. Or vice-versa: findmnt /home


6

You can use: mount for a list of all mounted filesystems and mount options for each of them; lsblk for a tree of block devices, size and mount point (if mounted); df for a list of mounted block devices, size, used space, available space and mount point.


5

Use parted to identify offset values. root@mysystem:~/# parted myimage.img GNU Parted 2.3 Using /root/myimage.img Welcome to GNU Parted! Type 'help' to view a list of commands. (parted) u Unit? [compact]? B (parted) print Model: (file) Disk /root/myimage.img: 8589934592B Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start ...


5

If you can increase the capacity depends on whether you have LVM installed or not and whether your filesystem supports growing (ext{2,3,4}, btrfs, reiserfs, xfsm, and maybe some others, do) If you do have LVM you can add the new disc add it to the current /home (or if that is not a separate partition /) using vgextend and lvextend. If you don't have LVM, ...


5

Use parted instead, possibly coupled with your filesystem's resizing command. parted is the engine underneath the GParted GUI. You can use it in either interactive command mode or directly from the command line. Before parted 3.0, the following command does what you are probably expecting, having learned about GParted: $ sudo parted /dev/sdb resize 1 1 ...


5

From the Wikipedia entry: [The] maximum disk size supported on disks using 512-byte sectors (whether real or emulated) by the MBR partitioning scheme (without using non-standard methods) is limited to 2 TB. 2TB = 2*1024*1024*1024*1024 = 2^41 = 2^32 * 2^9, and 2^9 is 512.


5

To illustrate the question in a simple and efficient manner, consider two scenarios: You install your favourite linux distribution on entire disk i.e. without any partitions: Suppose your system is crashed because operating system is unable to access some sectors and unable to boot. You lost some chunk of data due to bad sectors and because of that you ...


5

You're actually asking two questions. The easiest thing to do if you want to know where your home is: cd df -h . Or df -h $HOME Where is /tmp mounted? df -h /tmp ...etc. If you want to know what is mounted on a certain device, mount | grep ^/dev/sda1 (for example). Or mount | grep ^/dev/sd to see all the sd's.


4

A BIOS boot partition doesn't contain a filesystem; it's just a place to put some GRUB code that on an MBR disk would've been located immediately after the boot sector, before the start of the first partition. On a GPT disk, that area is used by the (larger) partition table and isn't available for bootloader code, so the bootloader code goes in a small ...


4

It can also be very orderly to have a separate /boot partition. On my machine, I have many distros and backups, each in their own partitions, but they all share the same /boot partition, which is where all kernels for all OS reside. Also, all distros point to my one and only copy of lilo.conf which is also in /boot, so I never have to guess what the heck is ...


4

This wasn't a limitation of the Linux distribution, but was a limitation of older BIOSes. bAck in those days, to ensure Linux could boot, all the boot related files were placed in their own partition which was made the first partition on the hard drive to ensure the boot loader fell within the first 1024 cylinders. Create a partition that is smaller than ...


4

Although on modern systems, a file's sectors can be accessed anywhere on a disk, it still makes sense to confine boot materials to their own boot partition, simply from the principle of "do not put all the eggs in in one basket". Suppose that the main filesystem is corrupt in such a way that some lower-stage bootloader is not able to read the next stage ...


4

The same tools that you can use for other files (generally) can also be used on block devices. This means that you can use, for example, xxd or hexdump to inspect the filesystem: $ sudo xxd /dev/sda2 | head -10 00000000: eb58 9053 5953 4c49 4e55 5800 0200 0000 .X.SYSLINUX..... 00000010: 0000 0000 0000 0000 3f00 ff00 0008 2000 ........?..... . 00000020: ...


4

This was asked recently but it was in the context of local disks. In that situation, there is a good reason to use a partition table on the disk even if you only intend to make it a single big partition spanning the entire disk: documenting the fact that the disk is actually in use, thus preventing accidents. I believe that the situation is different for ...


4

Both UUID of GPT partitions, and UUID of filesystems, are generated randomly when the partition/filesystem is created. You can check that they're version 4 UUIDs.


4

Linux itself mostly won't care. A few things won't be possible (e.g., installing a bootloader such as GRUB on the drive), but it sounds like that isn't an issue. Some software (udisks, for example) might fail to see it as a mountable filesystem, so it might work less well in desktop GUIs. If you attach this to a different OS, I'd expect both Mac OS and ...


4

The physical volume (PV) is simply the partition with LVM metadata added. You can't create the volume group (VG) without referring to the metadata, thus you have to first create the PV(s) that will be members of the VG. A physical extent (PE) is just that - the actual section of the disk that you're writing to, very similar to an old-style disk CHS ...


4

After you dd an image to a flash drive, the drive will be divided in 2 parts: the image partition with the image's size and a blank part. That's normal. To get your drive go like before, just format it: mkfs.vfat -I /dev/sdb (as root).


4

The command du will show you the disk space used by your files and directory. du -sh /home/* will show you the size of each subdirectory directly below the /home directory, afterwards depending on your preferences you might then: Either run the same command against one of these directories to manually step one level lower (for instance du -sh ...


3

If you're new, gparted is probably your friend as it's quite user-friendly for both the above options. Use it to create three partitions on /dev/xvdc of the required size for your partioning scheme. Once installed, run it as root: gparted /dev/xvdc Make sure you create the filesystems as well as the partitions. Use ext4 for the partition filesystems - ...


3

If the filesystem is ext2, ext3 or ext4, then you can use the command tune2fs to find out particulars about a given filesystem on a device. $ sudo tune2fs -l <dev> Example $ sudo tune2fs -l /dev/sda2 tune2fs 1.42.8 (20-Jun-2013) Filesystem volume name: <none> Last mounted on: /boot Filesystem UUID: ...


3

1: it doesn't have to do anything with primary/extended/logical partitions. 2: I think you wanted to say "logical" partition instead of "extended". 3: mkfs thinks your partition size if 0 bytes. It was very surely, because the kernel wasn't able to update the partition table after a repartitioning. After you edited the partition table, didn't you get some ...


3

This is going to be tricky to fix by hand. I hope you haven't modified any more data on this disk, apart from the broken partition table you wrote to it. Using sfdisk, fdisk, etc to create a backup of the partition table is a good idea (when you don't accidentally type the wrong command :) ). But for extra insurance I like to back up the boot sectors of my ...



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