# Best Hard Drive for Immich: NAS Storage Buying Guide for Large Libraries Hard drives become compelling when an Immich library grows beyond the comfortable cost of all-flash storage. The buying problem is not simply choosing the largest disk. You need enough usable capacity for originals and generated data, room for growth, a protection layout the server actually supports, and independent backup capacity that is not confused with RAID. ## Buying answer For a growing Immich library, favor internal SATA NAS or enterprise hard drives with a clearly identified capacity and warranty, then size the pool around future usable capacity rather than today’s folder size. Keep database/application data on local SSD storage and treat the HDD pool as the economical media layer. ## Buying guide ### Project the library before choosing a drive size A hard-drive purchase should solve the library you will have, not only the library you have today. Start with current originals, add realistic annual growth and choose a planning horizon. Then include generated media and free-space reserve before calculating the primary pool. This prevents a common mistake: filling a new array to a high percentage immediately and discovering that the next expansion requires replacing several drives at once. ### Usable capacity is the number that matters A 20TB label is raw manufacturer capacity, not a promise that every storage layout exposes 20TB of usable space to Immich. Redundancy, filesystem metadata, snapshots and reserve space all reduce what you can safely plan to fill. Compare drives by raw capacity and price per TB, but make the actual purchase decision from a usable-capacity target generated by the intended NAS, RAID or ZFS design. ### NAS drives versus enterprise drives Both NAS-oriented and enterprise SATA drives can be candidates for a home photo server, but the surrounding trade-offs differ. NAS lines often emphasize multi-bay operation and home/server warranties, while enterprise products may prioritize datacenter workloads and acoustics less. The correct choice depends on exact model, chassis cooling, warranty, noise tolerance and price. Do not buy by brand family alone when marketplace listings mix revisions and conditions. ### CMR and SMR need exact-model verification Recording technology can matter for rebuild behavior and sustained write workloads, especially in arrays. Marketplace titles sometimes advertise CMR, sometimes omit the detail, and occasionally use inaccurate keywords. Treat CMR or SMR as an exact-model specification. For an array purchase, verify the manufacturer data for the exact model number rather than assuming every capacity in a family uses the same recording method. ### SATA versus SAS is a compatibility boundary Many enterprise hard drives appear in both SATA and SAS variants that look nearly identical in product photos. A typical consumer NAS or motherboard SATA port does not become SAS-compatible simply because the connector looks related. For a typical consumer NAS or motherboard, choose the SATA version and verify the exact interface before ordering multiple disks; SAS requires a compatible controller and backplane. ### Drive count changes the economics Four smaller disks and two larger disks can provide similar raw capacity while behaving very differently for bays, parity, power, noise and future expansion. When bay count is scarce, higher-capacity drives can preserve an upgrade path. When budget matters more and bays are plentiful, a different mix may win. Model the entire pool cost, not just the cheapest individual disk. ### Plan rebuild space and cooling Large-capacity disks hold more data per device, so rebuilds and resilver operations can run for a meaningful period depending on array design and workload. A chassis that barely cools idle drives may behave differently while every disk is active. Keep airflow paths clear, monitor temperatures under sustained work and avoid packing an enclosure beyond the cooling design merely because the bays physically accept the drives. ### Warranty and seller condition are part of value A low price can reflect renewed stock, OEM packaging, recertified units or a seller warranty that differs from the manufacturer channel. The product card surfaces condition and warranty wording when available, but it cannot turn ambiguous marketplace text into guaranteed coverage. For valuable family archives, compare the savings against the replacement and support risk before treating the lowest price as the best deal. ### Noise and power matter in a home server An Immich server may sit in an office, closet or living area rather than a datacenter. High-capacity hard drives can differ in idle noise, seek behavior and power draw. Multiple drives multiply these effects. If the server is always on, consider acoustic location, vibration isolation, PSU headroom and airflow alongside capacity. A technically compatible disk can still be a poor home deployment if the chassis and room were not chosen for it. ### RAID is not the backup copy Redundancy helps a storage pool stay available through certain disk failures, but it does not create an independent copy of deleted, corrupted or stolen data. Keep backup capacity in the budget as a separate number. Keep independent backup capacity separate from primary raw storage so the same disks are not counted twice in the protection plan. ### Use price per TB after compatibility filters Hard drives are one of the places where price per TB is genuinely useful because media storage scales with capacity. Still, filter out the wrong interface, condition, form factor and ambiguous listing before sorting by value. A drive that cannot work in the target NAS has no useful price per TB. Only compare price per TB after confirming that the drive fits the target NAS, interface and workload. ### Build an expansion path before filling the array The cheapest first purchase can become the most expensive long-term plan if every bay is occupied with small drives. Decide what happens when the projected library doubles. You may want empty bays, a larger initial drive size, external backup rotation or a second NAS. Immich storage works best when growth is an expected event with a documented path rather than an emergency migration. ## Live Amazon prices See the canonical page for current or last-valid marketplace evidence.