Posts

File As Disk

About we can create Diskpartition using a file as image we can achieve this using ‘dd’ or ‘losetup’ Using: ‘dd’ create a file full of zeros using dd [s0x45ker--_(+_+)_--SysAdmin ~]$ dd if=/dev/zero of=imagefile bs=1M count=1024 #create a file full of zeros 1024+0 records in 1024+0 records out 1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.904085 s, 1.2 GB/s Format Filesystem Type next we must put a filesystem on it Note u can create different filesystem formats 'mkfs.

April 17, 2021 Read

Interacting With Disks

Mount The mount program allows attaching at any point in the tree structure; umount allows detaching them. The mount point is the directory where the filesystem is attached. It must exist before mount can use it; mkdir can be used to create an empty directory. If a pre-existing directory is used and it contains files prior to being used as a mount point, they will be hidden after mounting. These files are not deleted and will again be visible when the filesystem is unmounted.

April 17, 2021 Read

Storage Overview

Disks Disks are divided into partitions. In geometrical terms, these consist of physically contiguous groups of sectors or cylinders. A partition is a physically contiguous region on the disk. There are two partitioning layouts in use: MBR (Master Boot Record) GPT (GUID Partition Table). MBR dates back to the early days of MSDOS. The disk partition table is contained within the disk’s Master Boot Record (MBR), and is the 64 bytes following the 446 byte boot record.

April 17, 2021 Read

Why Disk Partition ?

Why Partition? There are multiple reasons as to why it makes sense to divide your system data into multiple partitions, including: Separation of user and application data from operating system files Sharing between operating systems and/or machines Security enhancement by imposing different quotas and permissions for different system parts Size concerns; keeping variable and volatile storage isolated from stable Performance enhancement of putting most frequently used data on faster storage media Swap space can be isolated from data and also used for hibernation storage.

April 17, 2021 Read

Backup Partition

Using dd for backup we can use dd or gfdisk The dd program is very useful for making copies of raw disk space. A common joke with `dd' is that is stands for data destroyer, so it should be noted that it’s a very dangerous utility. we will use one of the partition we created from earlier posts /dev/sdb1 **lets create a file within disk than backup the disk and delete the file and restore the disk**

April 16, 2021 Read

Linux Virtual Filesystem

Application programs read and write files , rather than dealing with physical locations on the actual hardware on which files are stored. Filesystems create a usable format on physical partition. Files and their names are an abstraction camouflaging the physical I/O layer. A UNIX-like filesystem uses a tree hierarchy: Directories contain files and/or other directories Every path or node is under the root directory. Multiple filesystems may be (and usually are) merged together into a single tree structure.

April 16, 2021 Read