RE: Need some infos for large backups

Large database backup can mean large bucks :-) I am currently involved with a large database (~80 - 100Gb) and we have come up with the following solution. The database will be split into about 10 instances. The primary instance will then have synonyms created in it to point to the tables in the other 9 instances. This means that as far as the application/client is concerned, there is only one database and one instance. With the 10 instances, we can run 10 x 10Gb backups in parallel. Obviously with 10 backups running at the same time, this will be a big hit on your server. A general rule would be to have no more than two tape devices on each SCSI bus however this may change according to your hardware. i.e. you need a further 5 SCSI controllers in your machine.($$$) The tape devices which we will be installing are DLT drives which can store 10Gb or 20Gb compressed on one tape. So no need for tape changers or tape array over multiple drives. One problem you now have is logical logging. Do you now add a further 10 exabyte drives or do you utilize the 10 DLT's??? A big benefit from this would be the amount of time required for a recovery. You have also opened the opportunity to move some of your instances onto another machine.($$$) The disadvantage for this solution is the fact that administration becomes a bit more difficult. :-( The solution has to fit your circumstances. How long does your database have to stay on-line? What are the requirements for recovery? Is there going to be a mirror system? If there is, is it a hot mirror? I'm sure that there are plenty of DBA's out there that will have comments on the above but my skin is thick, I can handle it. HTH --------------------------------------------- All opinions are my own Neil Stevenson nmsteven@eukcumbpo1.unitedkingdom.attgis.com Voice: +44 1236 851218 Fax: +44 1236 457459 ---------------------------------------------