When their luxury hotel client experienced server failure, TekConcierge kept the business running with Datto SIRIS, avoiding downtime and lost profits for the client. Disaster recovery as a service DRaaS is a critical offering for managed service providers MSPs to support their clients and grow their bottom line. Offsite backups are a type of data protection that provides a copy of a business' production system data, which is stored in a different location from where the original data is stored.
The backup rule states that you should have 3 copies of your data, 2 different backup formats, and 1 backup stored offsite. Thank you, you are now subscribed to Downtime: the Datto Blog! November 04, In addition, with volumes larger than about MB, there will be some performance degradation.
However, unlike FAT or HPFS, there are no "special" objects on the disk and there is no dependence on the underlying hardware, such as byte sectors.
To ensure reliability of NTFS, three major areas were addressed: recoverability, removal of fatal single sector failures, and hot fixing. NTFS is a recoverable file system because it keeps track of transactions against the file system. Under NTFS, a log of transactions against these components is maintained so that CHKDSK need only roll back transactions to the last commit point in order to recover consistency within the file system.
Under FAT or HPFS, if a sector that is the location of one of the file system's special objects fails, then a single sector failure will occur. NTFS avoids this in two ways: first, by not using special objects on the disk and tracking and protecting all objects that are on the disk. One of the major design goals of Windows NT at every level is to provide a platform that can be added to and built upon, and NTFS is no exception.
NTFS provides a rich and flexible platform for other file systems to be able to use. No longer is a data file a single stream of data.
Finally, under NTFS, a user can add his or her own user-defined attributes to a file. A hard link is when two different filenames, which can be located in different directories, point to the same data. This was done because Windows NT is a portable operating system and different disk technology is likely to be encountered at some point. Therefore, bytes per sector was viewed as having a large possibility of not always being a good fit for the allocation. This was accomplished by allowing the cluster to be defined as multiples of the hardware's natural allocation size.
For additional advantages of NTFS, see the following:. Currently, there is no file encryption built into NTFS. File and directory names can be up to characters long, including any extensions. Names preserve case, but are not case-sensitive.
Data Security. Data Backup. LSoft Technologies Inc. Toggle navigation. Sparse files Sparse files allow programs to create very large files but consume disk space only as needed.
Distributed link tracking NTFS provides a link-tracking service that maintains the integrity of shortcuts to files as well as OLE links within compound documents. You may ask. Here's an explanation: A firmware is a low-level software embedded into electronic devices to operate the device, or bootstrap another program to do it. This sector is called MBR.
MBR contains the following information: The boot loader, which is a simple program in machine code to initiate the first stage of the booting process A partition table , which contains information about your partitions. MBR gap can be used to place another piece of the boot loader program if needed.
This is when the operating system's logo fades in MBR's data structure limits the number of partitions to only four primary partitions. When making a partition, you can choose between primary and extended. After this is solved, we'll encounter the second limitation. And wait, there's more! For instance, you can have as many partitions as your operating system allows.
This is where the first-stage boot loader would reside in an MBR-partitioned disk After this first sector, the GPT data structures are stored, including the GPT header and the partition entries. This backup is called Secondary GPT. If this path cannot be found on your system, then your firmware is probably BIOS-based firmware. NVRAM contains the booting settings and paths to the operating system boot loader files.
Let's confirm that with the dmidecode command like so: sudo dmidecode -t 0 And the output would be: dmidecode 3. Formatting partitions When partitioning is done, the partitions should be formatted. Most operating systems allow you to format a partition based on a set of file systems.
These data structures are one aspect of a file system. Let's take the NTFS file system as an example. How it started, how it's going A file system is a set of data structures, interfaces, abstractions, and APIs that work together to manage any type of file on any type of storage device, in a consistent manner. Each operating system uses a particular file system to manage the files.
Or you can just use the exFat file system. But how about file systems in Linux distributions? When people talk about file systems, they refer to one of these layers or all three as one unit. Although these layers are different across operating systems, the concept is the same. The next layer is the virtual file system or VFS. So does this mean an operating system can use multiple file systems at the same time? The answer is yes! Can you guess what it is?
Yes, we're talking about the logical file system. A high-level architecture of the file system layers What does it mean to mount a file system?
However, there are times you need to mount a file system manually. Please note that the mount point should already exist as a directory. Inodes are identified by a unique number called the inode number. Inodes are associated with files in a table called inode tables. The inode also includes the address of the blocks allocated to the file; On the other hand, where exactly it's located on the storage device In an ext4 inode, the address of the allocated blocks is stored as a set of data structures called extents within the inode.
Whenever you open a file on Linux, its name is first resolved to an inode number. Having the inode number, the file system fetches the respective inode from the inode table. On NTFS, the metadata is stored differently, though. On most operating systems, you can grab metadata via the graphical user interface. Space Management Storage devices are divided into fixed-sized blocks called sectors.
Depending on the file size, the file system allocates one or more blocks to each file. The layout of a block group within an ext4 partition Each block group has its own data structures and data blocks.
Here are the data structures a block group can contain: Super Block: a metadata repository, which contains metadata about the entire file system, such as the total number of blocks in the file system, total blocks in block groups, inodes, and more.
Not all block groups contain the superblock, though. A certain number of block groups store a copy of the super as a backup. Group Descriptors: Group descriptors also contain bookkeeping information for each block group Inode Bitmap: Each block group has its own inode quota for storing files. A block bitmap is a data structure used to identify used and unused inodes within the block group. The number of inodes stored in this area is related to the block size used by the file system. Data Blocks: This is the zone within the block group where file contents are stored.
The layout of the first block group looks like this: The layout of the first block in an ext4 flex block group When a file is being written to a disk, it is written to one or more blocks within a block group.
Size vs size on disk Have you ever noticed that your file explorer displays two different sizes for each file: size, and size on disk. Size and Size on disk Why are size and size on disk slightly different? You can use the du command on Linux to see it yourself. What is disk fragmentation? Over time, new files are written to the disk, existing files get bigger, shrunk, or deleted. That's when new files need to be stored as fragments.
An example of a fragmented and non-fragmented file Let's make it more clear with an example. Imagine you have a Word document named myfile. This overhead applies to saving the file back to the disk as well. Fragmentation is one of the reasons some operating systems get slow as the file system ages.
Should We Care About Fragmentation these days? The short answer is: not anymore! Additionally, ext4 uses an allocation technique called delayed allocation. Delayed allocation actively reduces fragmentation and increases performance. Directories A Directory Folder in Windows is a special file used as a logical container to group files and directories within a file system.
On Linux, you can use the ls in a directory to see the directory entries with their associated inode numbers: ls -lai And the output would be something like this: drwxr-xr-x 14 root root Dec 1 Rules for naming files Some file systems enforce limitations on filenames. Why does this matter?
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