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My collaborator is splitting from his institute and wants help moving his application and data off the institute's network. And of course things are moving quickly.

He has 12 TB of image data on a 400 TB SAN, which is addressed over iSCSI.

The application server currently runs in a separate 1U Dell pizza box, runs on Windows Server 2003 for now (plan is to upgrade to 2012 when the app company certifies their product build) and the app officially only supports iSCSI; although a long-time tech rep at the company says he's seen it work with NFS. He says he only needs to run an SQL script to update the paths.

Here's my proposed workflow:

  • Setup a zpool (tank) on FreeBSD 10.2 on a Dell Precision T7400 with 5 6TB disks in either a RAIDZ1 or 4 disks in two mirror vdevs. Let's call this machine bohr
  • Set up an iSCSI targets with LUNs that point to volumes (images and images2)
  • Plug bohr into the institute's network (they're fine with that)
  • Mount the institute's SAN, as an initiator or via SMB
  • copy the data to the LUNs
  • point the application server at the new LUNs
  • Charles (the app company's rep) runs his SQL
  • Take bohr and the app server and set them up at the new site.

The only alternative I thought of was to make the app server do the transfer. It seems like it might actually slow things down, but would also avoid me having to set up bohr as an initiator.

My questions: am I making sense? Does the plan sound like it would work? Am I missing any steps? Does it make sense to also set up bohr to serve the same data over NFS simultaneously (for pulling data for other research uses) or should I require iscsi access for all clients?

  • Do you have downtime requirements and is it an hba initiator or just 2003 software iscsi initiator – Jacob Evans Sep 26 '15 at 5:05
  • thanks for responding! As I understand it, HBA is mainly a fibre channel thing? I plan to use just 2003 software iscsi initiator. I haven't gotten to put my hands on the pizzabox yet, but I'm told it's over ether and the IT guys were pretty emphatic they don't use fibre channel at all. I'm also updating the question a bit to reflect my new plan to use freebsd and zfs. – niels Sep 27 '15 at 19:59
  • HBA is just that, a hardware bus adapter, it CAN be iscsi, fiberchannel, SAS or whatever. – Jacob Evans Sep 28 '15 at 3:11
  • Very valid point. This is all pretty ghetto: I'm putting 4 6TB SATA disks in a Dell Precision T7400. There's no special raid card, HBA, or any other hardware. – niels Sep 28 '15 at 3:40
  • Ghetto isn't your problem, I would migrate their server to something with local disk if they are parting ways with the SAN – Jacob Evans Sep 28 '15 at 3:43
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  1. Backup your data
  2. Present both storage devices as iSCSI to the server
  3. Use the server to format your block storage in the same format as the other disk (I assume NTFS)
  4. Mirror your data to the new storage (pick your method xcopy, robocopy, etc)
  5. Stop all processes accessing old storage
  6. do a final mirror of the data
  7. Dismount old storage
  8. Change the drive letter of new storage to the previous mount's letter.
  9. Test everything, and backup your data

This is the safest method.

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