# DM-SMR vs HM-SMR vs HA-SMR: The Three SMR Models

> DM-SMR hides shingle management inside the drive and is designed to look like a conventional block device to the host. HM-SMR exposes zoned constraints and requires the host to issue writes according to zone rules. HA-SMR offers the zoned command interface while retaining backward compatibility with ordinary host behavior.

This context describes the Cloudzat canonical page at https://cloudzat.com/dm-smr-vs-hm-smr-vs-ha-smr/. Current or last-verified Amazon price and image status belongs on the canonical page and is intentionally not frozen here.

## Primary source
- [DM-SMR vs HM-SMR vs HA-SMR: The Three SMR Models](https://cloudzat.com/dm-smr-vs-hm-smr-vs-ha-smr/index.md): Clean Markdown version of the full Cloudzat guidance.

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