> > I have budget constraints then I can use only > user-level storage. > > > > until I discovered zfs I used subversion and git, > but none of them is designe > > d to manage gigabytes of data, some to be > versioned, some to be unversioned. > > > > I can't afford silent data corruption and, if the > final response is "*now* th > > ere is no *real* opensource software alternative to > zfs automatic checksummin > > g and simple snapshotting" I'll be an happy solaris > user (for data storage), > > an happy linux user (for everyday work), and an > unhappy offline windows user > > (for some video-related activity I can't do with > linux). > > Note that I don't wish to argue for/against > zfs/billtodd but > the comment above about "no *real* opensource > software > alternative zfs automating checksumming and simple > snapshotting" caught my eye. > > There is an open source alternative for archiving > that works > quite well. venti has been available for a few years > now. > It runs on *BSD, linux, macOS & plan9 (its native > os). It > uses strong crypto checksums, stored separately from > the data > (stored in the pointer blocks) so you get a similar > guarantee > against silent data corruption as ZFS. > > You can back up a variety of filesystems (ufs, hfs, > ext2fs, > fat) or use it to to backup a file tree. Each backup > results > in a single 45 byte "score" containing the checksum > of root > pointer block. Using this score you can retrieve the > entire > backup. Further, it stores only one copy of a data > block > regardless of what files or which backup it may > belong to. In > effect every "full backup" is an incremental backup > (only > changed data blocks and changed or new ptr blocks are > stored). > > So it is really an "archival" server. You don't take > snapshots but you do a backup. However you can nfs > mount a > venti and all your backups will show up under > directories > like <machine>/<yyyy>/<mm><dd>/<filesystem>. > > Ideally you'd store a venti on RAID storage. You can > even > copy a bunch of venti to another one, you can store > its > arenas on CDs or DVD and so on. > > It is not as fast as ZFS nor anywhere near as easy to > use and > its intended use is not the same as ZFS (not a > primary > filesystem). But for what it does, it is not bad at > all! > > Unlike ZFS, it fits best where you have a fast > filesystem for > speed critical use, venti for backups and RAID for > redundancy. > > Google for "venti sean dorward". If interested, go > to > http://swtch.com/plan9port/ and pick up plan9port (a > collection of programs from plan9, not just venti). > See > ttp://swtch.com/plan9port/man/man8/index.html for how > to use > venti.
thank you for the suggestion. after reading something about venti I like its features and its frugality (no fuss, no hype, only a reliable fs). however, having touched zfs before venti, I admit I like zfs more and furthermore this give me a reason to use opensolaris and maybe tomorrow dump linux entirely. I'd like to have time to play with plan9port and maybe also with inferno, but for now the descent can wait. > > I think for every fully digital people own data are > vital, and almost everyon > > e would reply "NONE" at your question "what level > of risk user is willing to > > tolerate". > > NONE is not possible. It is a question of how much > risk you > are willing to tolerate for what cost. Thankfully, > these > days you have a variety of choices and much much > lower cost > for a given degree of risk compared to just a few > years ago! I know no risk is impossible, but a checksumming fs with snapshots (mirrored on two disks used alternatively) is a good compromise for me (a professional-home user, with data I can't -or I'd like not to- loose). bye --- Stefano Spinucci This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
