Highly Available STorage

{{Short description|Distributed storage system}}

{{One source|date=June 2024}}

{{Infobox software

| name = Highly Available Storage

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| author = Pawel Jakub Dawidek

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| latest release date = {{Start date and age|2013|02|05|df=yes/no}}

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| programming language = C

| operating system = FreeBSD

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| genre = Distributed storage system

| license = FreeBSD License

| website = {{URL|https://wiki.freebsd.org/HAST}}

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Highly Available Storage (HAST) is a protocol and tool set for FreeBSD written by Pawel Jakub Dawidek, a core FreeBSD developer.

HAST provides a block device to be synchronized between two servers for use as a file system. The two machines comprise a cluster, where each machine is a cluster node. HAST uses a Primary-Secondary (or Master-Slave) configuration, so only one cluster node is active at a time.

HAST-provided devices appear like disk devices in the /dev/hast/ directory in FreeBSD, and can be used like standard block devices. HAST is similar to a RAID1 (mirror) where each RAID component is provided across the network by one cluster node.{{Cite web |date=2018-08-08 |title=Solved - How to create RAID1 for a entire disk with UFS and GPT? |url=https://forums.freebsd.org/threads/how-to-create-raid1-for-a-entire-disk-with-ufs-and-gpt.67066/ |access-date=2023-12-13 |website=The FreeBSD Forums |language=en-US}}