User-defined System Disk

[TMroy]

What is the system disk in TOS?
Before delving into the details, we first need to understand the concept of disk partitioning in TNAS. Why is it necessary to create partitions for disks? There are mainly two reasons. Firstly, to enhance performance, by dividing the hard drive into multiple partitions, we can optimize disk access, reduce fragmentation, and improve read and write efficiency. Secondly, for data security and backup purposes, storing important data in independent partitions makes it more convenient for data backup and recovery. In the event of a system failure or the need for a system reinstall, only the partition containing the operating system and programs needs to be formatted, while the user data partition remains unaffected.

When creating storage pools and volumes in the TOS system, the system automatically partitions and formats the disks used to create storage pools. Each disk is divided into four physical partitions: the boot partition, swap partition, system partition, and data partition.

The boot partition is the first partition on the TNAS disk and stores the system's boot loader. When the BIOS or uBoot is set to boot from the disk, the bootloader on this partition provides the boot for the system. In the TOS system, the file system of the boot partition is default to ext4, with a partition size of 300MB.

The swap partition is a special hard disk space in the Linux operating system, also known as virtual memory. When the system is running out of memory, a portion of less frequently used memory data is stored in the swap partition to free up memory space, ensuring the stable operation of the system. In the TOS system, the file system of the swap partition is default to ext4, and the size is set to 2GB by default.

The system partition is used to store the operating system, including the kernel, configuration files, user directories, programs, and databases, among other components. In the TOS system, the default file system for the system partition is ext4. Before TOS 5, the default size of the system partition was 2GB, and starting from TOS 5, the system partition size was adjusted to 8GB.

The data partition is used to store user data. Any disk space other than the boot partition, swap partition, and system partition will be allocated to the data partition, and its size depends on the total disk space.

In summary, the system disk refers to a disk that has been partitioned into boot, swap, system, and data partitions, serving as the storage medium for the bootloader, operating system, and database files.

What is a user-defined system disk?

A user-defined system disk allows users in the TOS system to define disks for system booting and data storage according to their own needs. In versions up to TOS 6, when users create storage pools, the system automatically creates complete four partitions for all involved disks and copies the bootloader and operating system to these disks. If there are multiple disks in TNAS, each disk is treated as a system disk, and the Swap partition and system partition on each disk are assembled into a RAID 1 array, ensuring that system configurations and database change data are backed up on each system disk, providing flexibility for disk replacement.
However, in these versions, each write operation needs to wait for all RAID 1 array disks to complete, which may affect performance.

TOS 6 introduces a new feature where users can customize the choice of disks for installing the system during system installation. Disks not selected will not contain the bootloader, operating system, and RAID 1 array, limiting the maximum number of system disks to 4, thus improving system efficiency.

What are the benefits of a user-defined system disk?

User-defined system disks bring many benefits. Firstly, by reducing the unnecessary number of system disks, system performance can be significantly improved, especially in TNAS environments with numerous disks, where the effect is more pronounced. Secondly, users can choose to install the system on SSDs with high random read and write capabilities, greatly improving the loading speed of the system and programs, further optimizing system performance. These advantages provide users with a more flexible and efficient disk management solution.

How to Customize the System Disk?

To customize the system disk, you need to follow the instructions on the installation page during the initial installation of the TOS system. Choose the disk for installing the system and check the corresponding options to complete the customization.

Please note the following points:
1. Customizing the system disk is only possible during the initial system installation. Once the system installation is complete, you won't be able to change, add, or remove system disks.
2. When there are multiple system disks, the failure of one system disk will not affect the normal operation of the system, ensuring the reliability of data and the stability of the system.

[Gremlin]

TOS 6 introduces a new feature where users can customize the choice of disks for installing the system during system installation. Disks not selected will not contain the bootloader, operating system, and RAID 1 array, limiting the maximum number of system disks to 4, thus improving system efficiency.

Does this mean that, in F5 units, there will be one drive that is never initialised with the OS partitions. How does this affect users with currently more than 4 drives installed? Which drive?

[TMwuu]

{L_BUTTON_AT}Gremlin

For systems that have previously installed more than four drives, as long as the hard drive is not lost, there will be no impact on data.

[Gremlin]

Let me clarify - when upgrading to TOS 6 and 5+ drives are already installed with raid OS, will there be any impact on the install or operational system?

[TMroy]

Even after the update, the original system disks will still be system disks because they have been added to the raid 1 array of swap and system partitions and will continue to be synchronized.

[Gremlin]

Thank you