6 Object storage can replace NAS for a large and growing share of unstructured file data, but not for everything. Network-attached storage has been the default home for file shares, home directories, project folders and application data for decades. As unstructured data grows into petabytes, NAS refresh cycles, licensing and scaling limits push organizations to ask which data really needs a file system and which could live more cheaply and durably on object storage. The answer depends on how each workload accesses data, how often it changes and what applications expect. This article explains where object storage replaces NAS well, where NAS still fits better, the access options that bridge the two and how to plan a transition. It is written for infrastructure managers facing a NAS refresh. For background, see object storage vs traditional storage and storage alternatives beyond SANs and NASes. How NAS and object storage differ NAS NAS presents a hierarchical file system over NFS or SMB. Applications and users open, modify, lock and rename files in place. NAS excels at shared file access with POSIX or Windows semantics, small random updates and compatibility with almost any application. Object storage Object storage stores data as objects in buckets, accessed over HTTP APIs such as S3. Objects are written whole and replaced rather than modified in place. Object storage excels at scale, durability, cost per terabyte and access from anywhere over standard APIs, with rich metadata and policies. Where object storage replaces NAS well Archives and cold file data Most file data is rarely touched after its first months. Completed projects, old shares, departed users’ folders and historical records can move to object storage at much lower cost, freeing NAS capacity. See how to move cold data off NAS filers. Backup targets Backup software increasingly writes to S3 directly, with immutability for ransomware protection. NAS used as a backup target is a common candidate for replacement. See is object storage cheaper than NAS for backup and archive. Media, images and large files Video, imagery, scientific data and other large files that are written once and read many times fit object storage naturally, especially when applications support S3. Application data for modern apps New applications, analytics platforms, AI pipelines and web services are typically built for S3. Data that was once placed on NAS because it was the only option can live on object storage. Data shared across sites or with external parties Object storage’s HTTP access and policies make it easier to share data across locations and organizations than traditional NAS. Where NAS still fits better Applications that require file system semantics, such as in-place updates, file locking or frequent renames, and cannot be changed. Latency-sensitive workloads with many small random reads and writes. Home directories and office documents with heavy interactive use, although file gateways and sync platforms can cover some of this. Legacy applications that only support NFS or SMB. For these, NAS remains appropriate, but it can often be smaller and faster because cold data has moved elsewhere. Bridging the gap: file access to object storage Several approaches let file-based users and applications use object storage: Cloud file gateways present SMB or NFS shares locally, caching active data and storing everything in object storage. See what a cloud file gateway is. NFS and SMB protocol support built into some object storage platforms, or via gateway software, with important caveats about semantics and performance. See NFS and SMB access to object storage. File system tiering, where NAS or parallel file systems move cold data to object storage while keeping it visible in the namespace. Sync and share platforms that give users folder-style access with object storage behind them. See self-hosted file sync and share storage. Cost and operational benefits Lower cost per terabyte, especially at petabyte scale with erasure coding instead of RAID and replication. Scale without forklift upgrades, adding nodes instead of replacing arrays. Built-in durability across nodes and sites. See erasure coding vs replication. Immutability for ransomware protection. Simpler backup for archive data, since object storage can protect itself with versioning, replication and object lock rather than nightly backups of huge file trees. A practical approach: shrink NAS, grow object Rather than replacing NAS outright, many organizations: Analyze file data by age, access, type and owner. Move cold data to object storage, through tiering, archiving tools or gateways. Move backup targets from NAS to object storage. Point new S3-capable applications at object storage. Right-size the remaining NAS for active, file-dependent workloads. This reduces NAS capacity and cost while keeping file semantics where they are genuinely needed. What a file analysis usually reveals When organizations analyze their NAS estates, the results are remarkably consistent. A large share of capacity, often the majority, holds files that have not been accessed for a year or more. Duplicate copies of the same datasets sit in different shares. Media, archives and backup files occupy far more space than active office documents. Departed users’ home directories and completed project folders remain on primary storage indefinitely. Snapshots and replicas multiply all of this. These findings are the business case for object storage: moving inactive and large-file data off NAS can shrink the NAS footprint dramatically, reduce the size of the next refresh and lower backup windows. Security and ransomware File shares are a primary target for ransomware, because attackers who compromise a user or server can encrypt everything that account can reach. Moving archives and backups to object storage with immutability limits that blast radius: even if active shares are hit, older data and backups remain intact. Separate credentials for object storage, and avoid mounting archive buckets broadly as writable file shares. See ransomware-proof backup. Organizational change Users are used to drive letters and folders. When data moves, provide clear communication about where archived data now lives, how to retrieve it and who to contact. Gateways and tiering stubs reduce disruption by keeping familiar paths. For S3-native access, offer simple tools and training for teams that will use it directly. Planning the transition Assess workloads For each share or application, record access patterns, protocols, performance needs, application dependencies and data age. Identify which can move as-is, which need gateways and which stay on NAS. Choose access methods Decide where users will access data directly over S3, through gateways, through tiering stubs or through sync platforms. Migrate carefully Preserve permissions, metadata and timestamps where needed, verify data after copying and communicate changes to users. See cold data migration strategy. Update backup and protection Archive data on object storage may no longer need traditional backup if protected with versioning, replication and object lock. Define the new protection model explicitly. Regional considerations Organizations in Europe, Japan and the Middle East often prefer on-premises object storage for file data that must remain in-country, such as public sector records, health data or industrial designs. Replacing NAS with on-premises object storage, rather than public cloud file services, keeps that data under local control while gaining scale and cost benefits. Checklist: object storage to replace NAS Analyze file data by age, access, type, owner and protocol. Identify workloads that need file semantics. Move cold data and backup targets to object storage first. Use gateways, tiering or sync platforms where file access is still needed. Point new applications at S3. Right-size remaining NAS for active workloads. Preserve permissions and metadata during migration. Redefine backup and protection for data on object storage. Keep data in required locations. Putting it together Object storage can replace NAS for archives, backup targets, media, large files, modern application data and cross-site sharing, which together often make up most unstructured data by volume. NAS remains the right tool for workloads that need full file system semantics or very low latency. The most effective strategy is to shrink NAS to what truly needs it, move everything else to scalable object storage and bridge the two with gateways, tiering or sync platforms where users still expect folders. Frequently asked questions Can object storage replace NAS? For archives, backups, media, large files and S3-capable applications, often yes. Workloads requiring full file semantics or very low latency usually stay on NAS. How do users access object storage like a file share? Through cloud file gateways, NFS or SMB access layers, file system tiering or sync and share platforms. Is object storage cheaper than NAS? Usually per terabyte at scale, thanks to erasure coding, standard hardware and scale-out growth without forklift upgrades. What data should move from NAS to object storage first? Cold data and backup targets typically move first, since they offer the biggest savings with the least disruption. Do I still need backups for data on object storage? It depends. Versioning, replication and object lock can provide protection, but define the protection model explicitly for each data set. Further reading See cloud file gateways, moving cold data off NAS filers, NFS and SMB access to object storage, distributed office file sharing and redefining NAS from edge to core.
