Thanks for everyone's feedback on my question. Richard, your comments were
just what I was looking for. I'm looking at TSM/HSM and also an LTFS-based
product from Crossroads Systems (Strongbox) that looks interesting.
If anyone is sharing an HSM-based filesystem via Samba, I'd like to hear your
experiences on that.
At 05:02 AM 4/10/2012, Richard Sims wrote:
>On Apr 9, 2012, at 2:22 PM, Paul Zarnowski wrote:
>> Does anyone who is using TSM for Space Management (aka HSM) know if it can
>> be used to share out filesystems using NFS (or CIFS)? Or are there timeout
>> problems that make this unworkable?
>You can, and we do it via NFS - but it can be a nightmare at times. Both HSM
>and NFS operate as kernel extensions: any problems thus become very severe. We
>had someone who thought it a good idea to have an HSM file system NFS-mounted
>to an FTP server for data feeding. That resulted in a hung FTP server system
>whenever data was being written faster than it could be migrated on the HSM
>server. Over the past weekend we had a situation where a user thought it
>reasonable to copy a movie file larger than the 64 GB HSM file system into
>that area: the file system was wedged, and because it was NFS-served as well,
>NFSd was hung; and the incoming files could not migrate because they were in
>an open state, even after the writing process was killed off: we had to reboot
>the server (which in turn somehow incited the failure of a IBM RAID adapter
>card and a marathon recovery effort that I'm just recovering from). A little
>known reality about HSM is that the space for a file must consist of
>contiguous blocks: you can have an HSM file system that is like 85% full as
>incited by a large file being written, and writing can proceed no further,
>because the file system is fragmented. Because of this, for file systems which
>get large files from users, we have an early morning job which forcibly
>migrates everything out of the file system to maximize free space.
>But don't let me discourage you from using HSM... :-)
> Richard Sims enduring at Boston University
Paul Zarnowski Ph: 607-255-4757
CIT Infrastructure / Storage Services Fx: 607-255-8521
719 Rhodes Hall, Ithaca, NY 14853-3801 Em: psz1 AT cornell DOT edu