On Fri, 2002-08-16 at 06:32, W. Wayne Liauh wrote: > I suppose if you set up a cron script to incrementally backup a > partition/directory or even one or more files every 10 seconds or so > (i.e., when you are doing a critical work, then turn if off when you're > done). That may be better than a same HD RAID? Right?
That may not work very well every 10 seconds, or even copies during live operation, because live files that are open and constantly changing will have unpredictable results when saved in this fashion at the filesystem layer. Oracle (and other databases) have "snapshotting" built in that can do backups of a live database, as well as replication. However, I really don't think the school needs even RAID-1 or any of these fancy safety methods. This would NOT be a production database. It will be used only for SQL statement practice on small databases that they create, and perhaps Java development at a Unix command-line. Currently they do Java development at a DOS command-line. It works okay, but WinMe DOS lacks tab-completion and is not case sensitive, while being somewhat limited by the 8.3 filename limitation. They also must constantly fuss with floppies. This Linux server would allow each student to store their Java files in their own account, accessible via Samba share in the lab, or SSH from the lab or home over the Internet. I'm thinking about using NFS and NIS+ to keep these server accounts in sync with the Sun Enterprise 450 a few doors down running the SunRay lab, but I am worried about security between the two rooms. Some genius used HUBS across a large portion of the campus, so security of NFS and NIS+ over the existing network would be quite bad. Would this work over a cheap, direct cross-over link between the two rooms? Then I guess the only problem would be the very expensive additional 100mbit Ethernet interface for the Sun E450. =( Perhaps NFS and NIS+ wouldn't be worth the effort? Then I would recommend the school to put a cheap CD burner into the Linux/Oracle/Java server. Warren
