NAS units are not the only option for adding storage to your workstations. Direct-Attached Storage (DAS) devices can also provide reliable expansion, especially when compared to pre-built NAS chassis.
Unlike NAS units, DAS devices offer a more affordable way to add storage without breaking the bank. A typical 4-bay storage server with faster Ethernet connections and an extra SSD slot can cost upwards of $450-$500, whereas a decent 2-bay DAS unit can be purchased for under $200. This makes DAS units an attractive option for those looking to expand their storage without sacrificing performance.
One key advantage of DAS units is that they connect to your server using USB ports, eliminating the need to upgrade your network stack. Assuming your server has a modern USB interface, you can enjoy blazing-fast transfer speeds with 10Gbps connectivity on sub-$200 devices.
DAS units also make file transfers a breeze, allowing you to easily access and share files between your Proxmox host, virtual guests, or other servers. This is particularly useful for GPU-powered development VMs, where fast data transfer can significantly enhance productivity.
Furthermore, DAS units offer an additional layer of redundancy for your Proxmox Backup Server. By setting up mirrored drives, you can increase the resilience of your backups and ensure that your data is safely stored even in the event of a primary drive failure.
Finally, using both NAS and DAS devices together can provide a flexible and cost-effective storage solution for home labs. With a budget-friendly consumer-tier NAS server as the base, adding a DAS unit allows you to expand storage options without hassle, making it an attractive option for those looking to grow their Proxmox setup.
Source: https://www.xda-developers.com/a-das-is-a-great-addition-to-your-proxmox-home-server