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Hail devs,Project Hail was, in part, conceived as an umbrella of libraries and services enabling the mating of a well known, Internet-standard API with a back-end that enables distributed storage. tabled is an example of this: it provides an application front-end compatible with S3 API, using Hail back-end services chunkd and CLD.
nfs4d is a second, work-in-progress example. nfs4d is a fully working NFSv4 front-end, waiting to be mated to the Hail back-end services.
A third example is something I poked at long ago, iSCSI. The vinzvault announcement got me thinking about the iSCSI target daemon that I had worked on, a while ago. vinzvault, sheepdog, DST, drbd, nbd and iSCSI all attempt to provide remote network attached storage, usually for storage on ephemeral virtual machines, similar to Amazon's Elastic Block Storage (EBS) on their EC2 grid.
I dusted off my "itd" (iSCSI target daemon) project, fixed a bunch of bugs, and got it working in the hopes that this might be useful to Hail or vinzvault or so.
itd is a remote iSCSI service exporting one or more slices of storage as a standard SCSI device on your system. It is based off of 'netbsd-iscsi' in Fedora, which is in turn based off an old, open source Intel codebase. netbsd-iscsi seemed a more pliable codebase than the very-nice SCSI TGT project.
The web browsable itd tree (with git:// URL for cloning) can be found at http://git.kernel.org/?p=daemon/distsrv/itd.git
As I write this email, I am borrowing a lot of networking code from tabled, to convert from GNet over to the more-flexible TCP server codebase found in tabled -- notably the asynchronous background TCP writing code in tabled. Hopefully will finish and commit this by the end of the weekend.
At that point, itd should be a fully compliant SCSI target, capable of reading/writing -- to a pre-allocated RAM space. Once that milestone is reached, the RAM storage may be replaced with Hail components, or other gadgets like MongoDB, to provide scalable, distributed storage.
Jeff  https://hail.wiki.kernel.org/index.php/Nfs4d  http://www.mail-archive.com/linux-cluster@xxxxxxxxxx/msg08555.html a SCSI "target" is a remote network server, in SCSI parlance. It is mated with an "initiator", which is SCSI's term for client.  well, only small WRITEs work at the moment. but READ is fully working at high speeds.
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