On 11/23/10 2:34 PM, upengan78 wrote:
<snip> One thing I am confused about and want to confirm do I really need to use spanning in Virtual tapes ? <snip> *How many DLEs, disklist entries, will you have, what are their relative sizes ? Only 1 entry for a amanda-network client server. Size is about 50G and grows by 100M-200M a day or data size sometimes stays as it is for 2-3 days.
Just a comment that this isn't making good use of Amanda. You will get a full backup of 50G, and then incrementals of 100M-200M on all the other days of the dump cycle. Making your vtapes all one size then wastes a lot of space, not to mention that the load is virtually all on one day of the cycle when the full backup is done.
You should break up the 50G into multiple pieces. Suppose there are, say, 10 directories in there, and that stays the same. Make each of those directories a disklist entry. Then Amanda's planner will decide when to do a full of each directory in such a way as to smooth out the load and the usage of space in the vtapes over the span of the dump cycle. If it works out well, and you have a 7 day dump cycle, then you should end up getting about 7G+/- every day after it gets started. Since each dle has to have a full backup before it can do incrementals, you could add one dle each day to your disklist to get a smoother start. Otherwise, the first time you run it, it will want to do a full of everything anyway.
Since you are not going to be using the space for anything else, make your vtapes about 10G. Give yourself, say, 21 of those. You will have some space left. If you set up a holding disk, then Amanda can run multiple dle's in parallel. Ideally, your holding disk should be somewhere else, but you could use the remaining 90G or so if you don't have anything else. I like to have a separate drive for a holding disk so that I'm not in competition for i/o bandwidth with anything that I might be backing up, or in your case with the vtapes.
That's just an example of how to go about it. It would give you a typecycle with 3 weeks of backup with 3 full dump cycles of 7 days.
-- --------------- Chris Hoogendyk - O__ ---- Systems Administrator c/ /'_ --- Biology& Geology Departments (*) \(*) -- 140 Morrill Science Center ~~~~~~~~~~ - University of Massachusetts, Amherst <[email protected]> --------------- Erdös 4
