The pitch in brief
Mannan's case rests on three claims:
- Cost: A beginner spending roughly $400 to $800 on a four-bay NAS is overpaying. A used corporate desktop for around $100 would be better value.
- Hardware: Her example is a Dell OptiPlex with a Core i5-8500 or better and at least 16 GB of RAM. She says four-bay NAS units often carry weak processors and 2 to 4 GB of soldered memory.
- Learning: She says NAS software hides Linux behind a polished interface. A bare Debian, Ubuntu Server or Proxmox VE install makes you learn SSH, systemd, Docker Compose, shell scripting, software RAID and SMART disk monitoring.
Those prices and specs are her examples. I did not independently verify them against current listings, and they vary by region, week and seller. Treat them as a rough picture, not market data.
Where the argument is strong
The learning argument is the most defensible part. A general-purpose Linux box lets you break things, read logs and fix them. That is a different skill from clicking through a vendor's control panel.
Docker's documentation describes Compose as a way to define multi-container applications in a YAML file. The file covers services, networks and volumes, and one command starts the whole stack. Writing and debugging those files by hand is useful, portable knowledge. It carries over to servers, CI pipelines and workplace IT.
An old PC also gives you flexibility. You can add RAM, swap drives and try virtualization. You can wipe it and start over without touching an appliance's locked-down firmware.
Where it needs qualifying
- "Black box" is too broad. Plenty of NAS products offer SSH access, container support or open-source firmware. Some are polished and restrictive, and some are not. A NAS is not automatically a poor learning tool. It is a different one, tuned for storage with less administration.
- "Cheaper" depends on the full cost. An old desktop can use more power at idle and make more noise than a purpose-built NAS. It may also have few drive bays and few SATA ports. Add the cost of drives, an enclosure and electricity before declaring a winner.
- Reliability and backups are separate from the hardware choice. Redundancy is not a backup. Whichever route you take, keep an independent copy of data you care about, preferably somewhere other than the server.
- The USB enclosure suggestion is risky as stated. Mannan suggests an external multi-bay USB/SATA enclosure for a "true storage pool." Compatibility, drive behavior and your storage software all matter. Not every enclosure suits a dependable array.
What the Proxmox documentation says
Proxmox VE is the one platform in her list that has detailed official hardware guidance, so it is worth checking against. Her suggestion fits, but it is not a bare command-line setup.
- Minimums versus recommendations: Proxmox's recommended hardware list says at least 2 GB of memory for the OS and Proxmox VE services, plus designated memory for guests. Its page for evaluation lists a lower minimum of 1 GB of RAM, a hard drive and one network card, marked for testing only. A 1 GB machine is not a useful home server.
- ZFS memory: For Ceph and ZFS, additional memory is required, approximately 1 GB for every TB of used storage. If you plan to learn ZFS, that is another reason her 16 GB RAM target is sensible.
- Virtualization support: On x86 hardware, Proxmox needs a CPU and motherboard with Intel VT or AMD-V. PCI(e) passthrough additionally needs VT-d or AMD-Vi. Check your used machine's firmware settings before you buy or commit.
- It has a web interface: Proxmox's install page describes a Debian-based system with a Proxmox kernel, KVM and container support. It says the install ISO includes a complete Debian system as well as all necessary Proxmox VE packages. Configuration is done through a browser. So Proxmox is closer to a hypervisor appliance you own than to a pure command-line lab.
- RAID caveat: Proxmox says neither ZFS nor Ceph is compatible with a hardware RAID controller. "Learning software RAID" is not one procedure. RAID levels, filesystems and controllers each have their own rules.
Third-party Proxmox sizing guides tend to recommend far more than the official minimums. Some suggest 8 GB of RAM or more for a home lab, and others suggest 32 GB. That is general community guidance, not a Proxmox requirement.
A safe way to try the old-PC route
- Check the machine. Inspect its condition and confirm the CPU supports virtualization if you want Proxmox. Count the SATA ports and drive bays, and check how much RAM it can take.
- Protect existing data. Back up anything important, and disconnect any drive you want to keep. The installer will erase the disk you point it at. Proxmox's own install page warns that existing data on the selected disks will be removed.
- Pick a platform to match your goal.
- Debian or Ubuntu Server suits you if you want to learn the Linux fundamentals directly.
- Proxmox VE suits you if you want to practice with virtual machines and containers.
- Add Docker the documented way. Follow Docker's current install instructions for your exact Debian or Ubuntu release. Docker's documentation also notes that firewall rules created with
nftare not supported on a system with Docker installed. Check how it interacts with your firewall setup. - Learn the habits. Use SSH, read systemd service logs, keep your Compose files in version control, and check drive health with SMART tools.
- Add storage later. Add disks when your data actually needs them, and keep a separate backup.
NAS or old PC?
| If your priority is... | Better starting point |
|---|---|
| Learning Linux, containers and virtualization | A repurposed PC |
| Simple, low-maintenance file storage | A NAS |
| Low power use and quiet operation | Often a NAS, but it depends on the model |
| Cheap experimentation | A used PC, if you already have one or find one cheaply |
Verdict
Mannan's strongest point is that hands-on administration teaches more than any vendor's settings page. If you want to learn Linux, a spare desktop is a cheap and low-risk way to start. Her verdict that a NAS is "a massive financial and educational mistake" goes further than the evidence supports.
A NAS is a perfectly reasonable choice if all you want is dependable storage. Whichever path you pick, back up your data, and double-check which disk you are about to wipe.