On Fri, Dec 06, 2002 at 04:47:39PM +0100, Joan Picanyol i Puig wrote: > Hi, > > I have some trouble understanding the last part of 'man dump', from "An > efficient method of...". My understanding is that the example means: > > 1. Take a level 0 dump once a month > 2. Take a level 1 dump once a week > 3. Take a level 3 dump on mondays, a level 2 on tuesdays, a level 5 on > wednesdays and so on until a level 9 on sundays. > > Am I missing something? What's so "efficient" from doing it this way > (why)?
It's a compromise between minimising the number of tapes required to restore the system to the state it was in on any particular date --- clearly just taking a level 0 dump every day means you only have to restore from one tape set --- and getting the most data possible onto a limited number of backup tapes --- best economy is achieved by doing a full level 0 backup once, and then each day just doing an incremental backup of what changed since the previous day: however leave too long between level 0 dumps and you're likely going to have a real chore wading through a mountain of tapes to get back to any particular state. Cheers, Matthew -- Dr Matthew J Seaman MA, D.Phil. 26 The Paddocks Savill Way Marlow Tel: +44 1628 476614 Bucks., SL7 1TH UK To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-questions" in the body of the message