Backup strategies for OnLine?

My client migrated from SE to OnLine, following my advice. I told him, Online had the better backup facilities... I'm sure it's true, but I have to prove it now.... I'm ready with the concept, but I'd like to hear your opinions about it: Every month a full dump level 0 every friday a dump level 1 every night a dump level 2 after receiving the incoming uucp data. I hope that's ok so far. Depends, of course, on the data. Question 1: Before dumping I force a checkpoint, after dumping I "backup" all logs to /dev/null (??? *shiver*) I _think_, I don't need them after archiving at any level. Any holes in there? I want to keep my client, even after a crash ;-) Question 2: Are there any formulas for the required number of logicals logs? Something like F(x) = n where x = avg(io) and n = #logs? Or is it just try and error? Question 3: Any further suggestions? hints? remarks? questions :-) ? Thank you for your opinions, tips and tricks, I'll summarize, if wanted, in about three weeks. Hoping for a bunch of input.... -svb.