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iSCSI

iSCSI is a storage protocol that carries SCSI commands over an IP network. On a NAS, it can present storage as a LUN to a compatible host, rather than as a shared folder.

What iSCSI means on a NAS

iSCSI, or Internet Small Computer Systems Interface, is a protocol for carrying storage commands over a standard IP network. A NAS with iSCSI support can typically present some of its storage as an iSCSI LUN, which a compatible host can access as block storage.

This differs from folder-based file sharing through protocols such as SMB or NFS. With iSCSI, the host generally manages the filesystem on the presented storage rather than browsing folders supplied by the NAS.

Why NASFit buyers may care

iSCSI matters when a product needs to provide storage to a compatible server, virtualization host, application system, or other client that expects block-level storage. In the observed NASFit catalog, iSCSI appears both as a general product capability and as a backup feature involving an iSCSI LUN.

It may be relevant if your intended setup specifically calls for an iSCSI target or LUN. It is less important when you only need ordinary shared folders, media storage, or desktop file access through SMB, NFS, FTP, or similar protocols.

What the label does not tell you

An “iSCSI support: Yes” flag confirms a listed capability, but it is not a quality rating. It does not by itself describe:

  • How many LUNs or targets the product supports
  • Whether thin provisioning, snapshots, cloning, or reservation features are available
  • Which host operating systems or applications are supported
  • Network speed, storage performance, or concurrent-user limits
  • Whether iSCSI is available for general storage, backup, or both

Catalog entries can also list iSCSI among supported network protocols without providing the complete implementation details. A truncated protocol string should not be treated as a complete specification.

What to check on a product page

Look for the exact wording used for iSCSI, including whether the page lists an iSCSI target, an iSCSI LUN, or iSCSI only as part of a backup feature. Check whether the product page provides details about LUN or target limits, supported host environments, network interfaces, and related storage features.

Also distinguish iSCSI from nearby file-sharing options. SMB, NFS, FTP, and SFTP generally describe file or transfer access, while iSCSI describes block-storage access. If the page does not state a particular compatibility or feature detail, it remains unknown rather than implied by the iSCSI label.

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