Computer crash calls for Full backup?
When one's PC crashes (power outage, Windows crash, whatever), does this call for/require/suggest that instead of an Incremental one next run a Full backup to start a new chain?
(With Norton Ghost I always needed to, to avoid a very length "reconciling" stage.)
Thank you very much for the kind reply, tuttle!
I think with Ghost, the long* post-crash Incrementals were related to that Ghost (and, I recall reading somewhere, ATI) doesn't just identify changes when an Incremental backup begins, but in fact does so continuously.
Given your reply, I'm guessing that ATI is somehow less bothered (than Ghost) by the way a crash causes it to 'take it's eye off the ball' of keeping track of changes. Perhaps I might even infer that ATI writes the changes it identifies on some schedule better than Ghost does.
*even longer than Full!
I do not recall seeing this with Norton Ghost, or it predecessor PowerQuest product. Might just have been lucky.
Or perhaps I was UNlucky.
Regardless, unless what I read somewhere about these products keeping track of changes continuously (instead of just at backup time) was wrong, it seems to me clearly optimal to create Fulls after a crash (lest some change too soon before the crash not have been logged yet).
A full is the safest bet. incrementals and differentials save time and space, but they are less reliable (although pretty reliable for the most part), the more you have and the longer you go. Differentials are really just the original full and the last differentail, but imagine if your full was long ago - that differential could be just as large as the full.
Incrementals are good for short periods of time (personally, I never go more than a week with incrementals with one incremental a day). You have to think, if your incrementals go bad for some reason, how far back are you willing to go to recover - all the way back to that original full? If it's been a week, probably. If it's been a year, probably not.
So for me... I stopped incrementals. I do 1 weekly full, followed by 4 differentials, every other day. I keep 3 or 4 backup chains (roughly 3-4 weeks) and that suits my backups fine. Everyone will have their own needs based upon how much data they need to backup, how often, how far back they're willing to go if they need to recover and how long it takes to do a full backup.
"I never go more than a week with incrementals with one incremental a day"
I've been doing exactly that.