In our last post we discussed that the upcoming ArcaOS 5.1.0 release will be able to make use of laptops and desktops that only support booting in so-called UEFI mode.

When booting ArcaOS in UEFI mode, the disk partitioning scheme may use the traditional Master Boot Record (MBR) or the newer GUID Partition Table (GPT). Although MBR has been extended to support disks up to 2TB, with ever-growing disk sizes, this may be too limiting for devices which could otherwise support handling more data than this. Also, if installing to a disk which is already configured using GPT, releases of ArcaOS prior to 5.1.0 require a full wipe and repartition of the disk. This inconvenience should no longer be an issue in ArcaOS 5.1.

Thus, ArcaOS 5.1.0 will be able to utilize GPT disk layouts with the following benefits:

• Support for hard disks and solid state drives larger than 2TB attached to AHCI or NVMe storage controllers.
• On systems equipped with a single drive and Windows pre-installed using a GPT layout, there should be no need to wipe and repartition, as long as there is room for ArcaOS to create at least one partition for itself.
• GPT eliminates many of the LVM issues you may have encountered in the past when preparing a disk to install ArcaOS next to other operating systems, such as Linux and Windows because ArcaOS will use the same LBA partition alignment method (for GPT disk layouts) as these other operating systems.

GPT usage has been integrated into the ArcaOS installation partitioning tool (Logical Volume Manager), giving you a seamless experience while installing and maintaining ArcaOS.

Of course, ArcaOS 5.1.0. will continue to support your existing hard disks that have been partitioned using an MBR disk layout, too. In fact, a mix of GPT and MBR disks is also possible, and you will also be able to install ArcaOS in a UEFI environment on an MBR disk (GPT is completely optional, and never a requirement).

It is also important to remember that while ArcaOS 5.1.0 will support hard disks and SSDs larger than 2TB, OS/2 filesystems are currently limited to 2TB per partition. Thus, in order to fully utilize, say, a 12TB device for ArcaOS, you would need to partition this into multiple volumes, each no more than 2TB in size. (Also, for volumes in excess of 64GB, you must select JFS as the filesystem.)